Port Channels and LACP

This chapter describes channel groups, port channels, port channel interfaces, and the Link Aggregation Control Protocol (LACP). This chapter contains the following sections:

Port Channel Introduction

Arista’s switching platforms support industry-standard link aggregation protocols. Arista switches optimize traffic throughput by using MAC addressing, IP addressing, and services fields to effectively load share traffic across aggregated links. Managers can configure multiple ports into a logical port channel, either statically or dynamically through the IEEE Link Aggregation Control Protocol (LACP). Various negotiation modes are supported to accommodate different configurations and peripheral requirements, including LACP fallback to support devices that need simple network connectivity to retrieve images or configurations prior to engaging port channel aggregation modes.

Arista’s Multi-chassis Link Aggregation protocol (MLAG) supports LAGs across paired Arista switches to provide both link aggregation and active/active redundancy.

Port Channel Conceptual Overview

Channel Groups and Port Channels

A port channel is a communication link between two switches supported by matching channel group interfaces on each switch. A port channel is also referred to as a Link Aggregation Group (LAG). Port channels combine the bandwidth of multiple Ethernet ports into a single logical link.

A channel group is a collection of Ethernet interfaces on a single switch. A port channel interface is a virtual interface that serves a corresponding channel group and connects to a compatible interface on another switch to form a port channel. Port channel interfaces can be configured and used in a manner similar to Ethernet interfaces. Port channel interfaces are configurable as Layer 2 interfaces, Layer 3 (routable) interfaces, and VLAN members. Most Ethernet interface configuration options are also available to port channel interfaces.

Port Channel Subinterfaces

Port channel subinterfaces divide a single port channel interface into multiple logical L3 interfaces based on the 802.1q tag (VLAN ID) of incoming traffic. Subinterfaces are commonly used in the L2/L3 boundary device, but they can also be used to isolate traffic with 802.1q tags between L3 peers by assigning each subinterface to a different VRF.

For further details about subinterfaces, see Subinterfaces.

Link Aggregation Control Protocol (LACP)

The Link Aggregation Control Protocol (LACP), described by IEEE 802.3ad, defines a method for two switches to automatically establish and maintain link aggregation groups (LAGs, also called channel groups or port channels). Using LACP, a switch can configure LACP-compatible ports into a dynamic LAG. The ports try to complete LACP negotiation automatically with the linked ports (also configured as a dynamic LAG) on the partner switch. The maximum number of ports per LAG varies by platform; numbers for each platform in the latest EOS release are available here: https://www.arista.com/en/support/product-documentation/supported-features.

Static LAGs

In static mode (with the channel-group mode configured as on on the member interfaces), the switch aggregates links without an awareness of LAGs on the partner switch and without LACP negotiation. The member ports do not send LACP packets or process inbound LACP packets on static LAGs. Packets may drop when static LAG configurations differ between switches.

Dynamic LAGs

Dynamic LAGs are aware of their partners’ port-channel states. Interfaces configured as dynamic LAGs are designated as active or passive.

  • Active interfaces send LACP Protocol Data Units (LACP PDUs) at a rate of one per second when forming a channel with an interface on the peer switch. An aggregate forms if the peer runs LACP in active or passive mode.
  • Passive interfaces only send LACP PDUs in response to PDUs received from the partner. The partner switch must be in active mode and initiates negotiation by sending a LACP packet. The passive mode switch receives and responds to the packet to form a LAG.

An active interface can form port channels with passive or active partner interfaces, but port channels are not formed when the interface on each switch is passive.

Table 12-1 summarizes the effect of different LACP mode combinations:

Table 1. LACP Mode Combinations

Switch 1

Switch 2

Comments

active

active

Links aggregate when LACP negotiation is successful.

active

passive

Links aggregate when LACP negotiation is successful.

passive

passive

Links do not aggregate because LACP negotiation is not initiated.

on (static)

on (static)

Links aggregate without LACP.

on (static)

active or passive

Links aggregate on the static switch without LACP; links do not aggregate on the other switch, and no port-channel connection is established with the partner.

During synchronization, interfaces in dynamic LAGs transmit one LACP PDU per second. After synchronization is complete, interfaces exchange one PDU every thirty seconds, facilitated by a default timeout of 30 seconds and a failure tolerance of three. Under these parameters, when the switch does not receive a LACP PDU for an interface during a ninety-second period, it records the partner interface as failed and removes the interface from the port channel.

Fallback Mode

An active interface that is not in fallback mode does not form a LAG until it receives PDUs from, and negotiates with its peer. Fallback mode allows an active LACP interface to maintain a LAG without receiving PDUs from its peer. The fallback timer specifies the period the LAG waits to receive a peer PDU. Upon timer expiry, the port channel reverts to its configured fallback mode if one is configured.

Static fallback: the port channel maintains one active port while in fallback mode; all its other member ports are in standby mode until a LACP PDU is received by the port channel. All member ports send (and can receive) LACP PDUs, but only the active port sends or receives data.

Individual fallback: all member ports act as individual switch ports while in fallback mode. Individual port configuration (rather than port channel configuration) is active while the port channel is in fallback mode, with the exception of ACLs. This includes VLAN membership. All member ports send and receive data, and continue to send LACP PDUs. As soon as a LACP PDU is received by a member of the port channel, all ports revert to normal port-channel operation.

The switch uses a link aggregation hash algorithm to determine the forwarding path within a link aggregation group. The IP and MAC header fields can be selected as components of the hash algorithm.

Port Channel Configuration Procedures

Configuring a Channel Group

Creating a Channel Group

The channel-group command assigns the configuration-mode Ethernet interfaces to a channel group, creates the channel group if it does not already exist, and specifies LACP attributes for the channel.

Channel groups are associated with a port channel interface immediately upon their creation. A command that creates a new channel group also creates a port channel with a matching ID. The port channel is configured in port-channel configuration mode. Configuration changes to a port channel interface propagate to all Ethernet interfaces in the corresponding channel group.

LACP is enabled on the member interfaces by setting the channel-group mode to active or passive. Setting the mode to on disabled LACP on the member interfaces and creates a static channel group.

Example:
These commands assign Ethernet interfaces 1 and 2 to channel group 10 (creating the channel group if it does not already exist), enable LACP on those interfaces, and place the channel group in a negotiating state.
switch(config)#interface ethernet 1-2
switch(config-if-Et1-2)#channel-group 10 mode active
switch(config-if-Et1-2)#

Adding an Interface to a Channel Group

The channel-group command is also used to add the configuration mode interface to an existing channel group. When adding channels to a previously created channel group, the channel-group mode for the new channel must match the mode for the existing group.

Example:
These commands add Ethernet interfaces 7 through 10 to previously created channel group 10, using the channel-group mode (active) under which it was created.
switch(config)#interface ethernet 7-10
switch(config-if-Et7-10)#channel-group 10 mode active
switch(config-if-Et7-10)#

Removing an Interface from a Channel Group

The no channel-group command removes the configuration mode interface from the specified channel group. Deleting all members of a channel group does not remove the associated port channel interface from running-config.

Example:
These commands removes Ethernet interface 8 from previously created channel group 10.
switch(config)#interface ethernet 8
switch(config-if-Et8)#no channel-group
switch(config-if-Et8)#

Deleting a Channel Group

A channel group is deleted by removing all Ethernet interfaces from the channel group. A channel group’s LACP mode can be changed only by deleting the channel group and then creating an equivalent group with a different LACP mode. Deleting a channel group by removing all Ethernet interfaces from the group preserves the port channel interface and its configuration settings.

View running-config to verify the deletion of all Ethernet interfaces from a channel group.

Configuring a Port Channel Interface

Creating a Port Channel Interface

The switch provides two methods for creating port channel interfaces:

  • creating a channel group simultaneously creates an associated port channel.
  • the interface port-channel command creates a port channel without assigning Ethernet channels to the new interface.

The interface port-channel command places the switch in interface-port channel configuration mode.

Example:
This command creates port channel interface 8 and places the switch in port channel interface configuration mode.
switch(config)#interface port-channel 8
switch(config-if-Po8)#

Deleting a Port Channel Interface

The no interface port-channel command deletes the configuration mode port channel interface and removes the channel group assignment for each Ethernet interface assigned to the group associated with the port channel interface. Removing all Ethernet interfaces from a channel group does not remove the associated port channel interface from running-config.

Configuring Port Channel Subinterfaces

When configuring subinterfaces on a port channel interface (the virtual interface associated with a port channel), the following restrictions apply:

  • An L3 interface with subinterfaces configured on it should not be made a member of a port channel.

    • An interface that is a member of a port channel should not have subinterfaces configured on it.
    • A subinterface cannot be made a member of a port channel.

Port channel subinterfaces are otherwise configured similarly to Ethernet subinterfaces. For additional information, see Subinterfaces.

Configuring LACP

Configuring the Channel-group Mode

The channel-group mode is configured when a channel group is created using the channel-group command. A channel group’s mode cannot be modified without deleting the entire channel group, but it can be modified without deleting the port channel interface associated with the channel group. The mode setting defines whether the port channel is static or dynamic, and whether a dynamic port channel is active or passive.

Examples:
  • These commands create a dynamic channel group and place it in LACP active mode.
    switch(config)#interface ethernet 1-2
    switch(config-if-Et1-2)#channel-group 10 mode active
    switch(config-if-Et1-2)#
  • These commands create a static channel group.
    switch(config)#interface ethernet 4-5
    switch(config-if-Et4-5)#channel-group 11 mode on
    switch(config-if-Et4-5)#

Configuring the System Priority

Each switch is assigned a globally unique system identifier by concatenating the system priority (16 bits) to the MAC address of one of its physical ports (48 bits). The system identifier is used by peer devices when forming an aggregation to verify that all links are from the same switch. The system identifier is also used when dynamically changing aggregation capabilities in response to LACP information; the system with the numerically lower system identifier is permitted to dynamically change advertised aggregation capabilities.

The lacp system-priority command configures the switch’s LACP system priority.

Example:
This command assigns the system priority of 8192 to the switch.
switch(config)#lacp system-priority 8192
switch(config)#

Configuring Port Priority

LACP port priority determines the port that is active in a LAG in fallback mode. Numerically lower values have higher priority. Port priority is supported on port channels that are enabled with LACP physical interfaces.

The lacp port-priority command sets the aggregating port priority for the configuration mode interface.

Example:
This command assigns the port priority of 4096 to Ethernet interface 1.
switch(config-if-Et1)#lacp port-priority 4096
switch(config-if-Et1)#

Configuring the LACP Packet Reception Rate

The lacp timer command sets the reception rate of LACP packets on the local device for the interface being configured. This command supports the following reception rates:

  • normal: LACP packets are received at the following rates:

    • 30 seconds for synchronized interfaces.
    • One second for interfaces that are being synchronized.
  • fast: LACP packets are received every second.
Example:
This command sets the LACP reception rate to one second on the Ethernet interface 4.
switch(config-if-Et4)#lacp timer fast
switch(config-if-Et4)#

Configuring LACP Fallback

Fallback mode (static or individual) is configured on a port channel interface with the port-channel lacp fallback command. The fallback timeout interval is configured with the port-channel lacp fallback timeout command. Fallback timeout settings persist in running-config without taking effect for interfaces that are not configured into fallback mode. The default fallback timeout period is 90 seconds.

Examples:
  • These commands enable LACP static fallback mode, then configure an LACP fallback timeout of 100 seconds on port channel interface 13. If LACP negotiation fails, only the member port with the lowest LACP priority will remain active until an LACP PDU is received by one of the member ports.
    switch(config)#interface port-channel 13
    switch(config-if-Po13)#port-channel lacp fallback static
    switch(config-if-Po13)#port-channel lacp fallback timeout 100
    switch(config-if-Po13)#show active
    interface Port-Channel13
     port-channel lacp fallback static
     port-channel lacp fallback timeout 100
    switch(config-if-Po13)#
  • These commands enable LACP individual fallback mode, then configure an LACP fallback timeout of 50 seconds on port channel interface 17. If LACP negotiation fails, all member ports will act as individual switch ports, using port-specific configuration, until a LACP PDU is received by one of the member ports.
    switch(config)#interface port-channel 17
    switch(config-if-Po17)#port-channel lacp fallback individual
    switch(config-if-Po17)#port-channel lacp fallback timeout 50
    switch(config-if-Po17)#show active
    interface Port-Channel17
     port-channel lacp fallback individual
     port-channel lacp fallback timeout 50
    switch(config-if-Po17)#

Configuring Minimum Links

The port-channel min-links command specifies the minimum number of interfaces that the configuration mode LAG requires to be active. If there are fewer ports than specified by this command, the port channel interface does not become active.

Note: In static LAGs, the min-links value must be met for the LAG to be active. The LAG will not become active until it has at least the min-links number of functioning links in the channel group. If failed links cause the number to drop below the minimum, the LAG will go down and administrator action will be required to bring it back up. In dynamic LAGs, the LACP protocol must determine that at least min-links physical ports are aggregable (they are physically compatible and have the same keys both remotely and locally) before it begins negotiating to make any ports active members of the port-channel. However once negotiation begins, an error on the partner’s side or an error in programming of member interfaces can cause the LAG to become active with fewer than the minimum number of links. EOS evaluates min-links after min-links-review-timeout (linearly proportional to configured min-links) when LACP protocol collecting and/or distributing state changes. If the number of active member interfaces in a port-channel is less than configured min-links, it brings the corresponding port-channel Link Down and syslogs LAG-4-MINLINK_INTF_INSUFFICIENT message. If additional interfaces get programmed as collecting and distributing, EOS re-evaluates min-links on the port-channel. If sufficient number of interfaces are available to be a part of port-channel, then all interfaces of the corresponding port-channel are re-enabled for LACP negotiation and the port-channel becomes Link Up. LAG-4-MINLINK_INTF_NORMAL is syslogged after min-links-review-timeout if the min-links condition is satisfied; otherwise LAG-4-MINLINK_INTF_INSUFFICIENT is syslogged and the port-channel goes Link Down. If an interface remains in collecting state but not in distributing state for min-links-review-timeout, it is moved out of collecting state. It is periodically re-enabled after min-links-retry-timeout (which is 200 seconds) till it progresses to collecting and distributing. Meanwhile, if a port-channel becomes Link Up because sufficient number of interfaces progressed to collecting and distributing states, then this interface is enabled for LACP negotiation.
Example:
This command sets four as the minimum number of ports required for port channel 5 to become active.
switch(config-if-Po5)#port-channel min-links 4
switch(config-if-Po5)#

Configuring Minimum Links Review Interval

The port-channel min-links review interval command enables or disables timer based min-links review feature for all port-channels. The timer based min-links feature is enabled when all of the following conditions are true. It is disabled otherwise:
  • The min-links configured is greater than 1.
  • LACP fallback is disabled.
  • The number of interfaces configured in the port-channel is more than min-links.
  • The number of active member interfaces in the port-channel is less than min-links.
  • The default timer values are:

    • min-links-review-timeout = min-links-timeout-base + f (configured min-links)
    • min-links-timeout-base = 180 seconds
    • min-links-retry-timeout = 360 seconds

Displaying Port Channel Information

Port channel information is accessed using some of the show commands listed under Interface Display Commands. Ensure that while using the show interfaces counters rates command to view the rate information of a port channel, rate values for the individual member ports are less inaccurate than rate values of the port channel.

Both the port channel rate and the individual port rates are calculated approximations; the rate value of a port channel might vary from the total of the rates for the member ports. The discrepancy is likely to be larger for port channels with fewer ports, and will be most obvious in single-port port channels.

Load Balancing Hash Algorithms

The switch balances packet load across multiple links in a port channel by calculating a hash value based on packet header fields. The hash value determines the active member link through which the packet is transmitted. This method, in addition to balancing the load in the LAG, ensures that all packets in a data stream follow the same network path.

In network topologies that include MLAGs or multiple paths with equal cost (ECMP), programming all switches to perform the same hash calculation increases the risk of hash polarization, which leads to uneven load distribution among LAG and MLAG member links. This uneven distribution is avoided by performing different hash calculations on each switch routing the paths.

The port-channel load-balance command specifies the seed for hashing algorithms that balance the load across ports comprising a port channel. Available seed values vary by switch platform.

Example:
This command configures the hash seed of 10 on 7150 Series (FM6000 platform) switches.
switch(config)#port-channel load-balance fm6000 10
switch(config)#

Load Balance Hash Algorithms on 7048 and 7500 Series Switches

One command configures the load balance hash algorithm on 7048 and 7500 Series switches:

  • port-channel load-balance petraA fields ip: controls the hash algorithm for IP packets by specifying the algorithm’s use of IP and MAC header fields. Fields that the command can specify include source and destination IP addresses, source and destination port fields (for TCP and UDP packets), and the entire MAC address header.

The hash algorithm for non-IP packets is not configurable and always includes the entire MAC header.

Example:
These commands configure the load balance algorithm for IP packets by using the entire MAC header.
switch(config)#port-channel load-balance petraA fields ip mac-header
switch(config)#

Load Balance Hash Algorithms on 7500E Series Switches

One command configures the load balance hash algorithm on 7500E Series switches:

  • port-channel load-balance arad fields ip: controls the hash algorithm for IP packets by specifying the algorithm’s use of IP and MAC header fields. Fields that the command can specify include source and destination IP addresses, source and destination port fields (for TCP and UDP packets), and the entire MAC address header.

The hash algorithm for non-IP packets is not configurable and always includes the entire MAC header.

Example:
These commands configure the load balance algorithm for IP packets by using the entire MAC header.
switch(config)#port-channel load-balance arad fields ip mac-header
switch(config)#

Dynamic and Symmetric LAG Hashing

Dynamic LAG hashing enables high link utilization and highly even distribution among LAG members by employing a randomized hashing algorithm. Symmetric LAG hashing allows the two flows of a bidirectional communication link, even when the two flows enter the switch on different ingress ports, to be hashed to the same member of a LAG on egress.

Dynamic and symmetric LAG hashing policies are enabled via named port-channel load-balancing profiles. LAG load-balancing policies can be provisioned on per line-card basis using these profiles. Load-balancing profiles can be used to provision all LAG load-balance attributes, including hash polynomials, hash seeds, and hash fields.

When no specific LAG hashing profile is assigned to a line card, then a global LAG hashing profile can be defined and applied to all the line cards with no LAG hashing defined on them.

Note, if no profile is selected as global profile then the default profile takes the precedence and set as a global profile. The default profile is reserved and if it is set as a global profile it cannot be deleted, if the profile is deleted then the following warning message is displayed.

Note: When a global profile is already set and if some other profile is tried to configured as a default profile the following warning message is displayed “! A global load balancing profile myProfile is currently active. This setting will not take effect.”
Examples:
  • These commands configure a load balance profile for symmetric hashing.
    switch(config)#load-balance policies
    switch(config-load-balance-policies)#load-balance arad profile
    switch(config-sand-load-balance-profile-symmetric-profile-1)#hash symmetric
    switch(config-sand-load-balance-profile-symmetric-profile-1)#show active
    load-balance policies
     load-balance arad profile symmetric-profile-1
    hash symmetric
  • These commands configure a load balance profile for dynamic hashing.
    switch(config)#load-balance policies
    switch(config-load-balance-policies)#load-balance arad profile
    switch(config-sand-load-balance-profile-dynamic-hash-profile-1)#distribution 
    clock
    switch(config-sand-load-balance-profile-dynamic-hash-profile-1)#show active
    load-balance policies
     load-balance arad profile dynamic-hash-profile-1
    distribution clock
  • This command assigns a named load-balancing profile to a linecard.
    switch(config)#port-channel load-balance module 3-7 sand profile Linecard5
    switch(config)#
  • This command unassigns a named load-balancing profile to a linecard.
    switch(config)#no port-channel load-balance module 3-7 sand profile Linecard5
    switch(config)#
  • This command configures a global profile on all line cards on which LAG hashing is not defined.
    switch(config)#port-channel load-balance sand profile myGlobalProfile
    
  • These commands designates a default profile as a global profile, if no other profile is set as a global profile.
    switch(config)#load-balance policies
    switch(config-load-balance-policies)#load-balance sand profile default
  • These commands configure a hash seed in a profile and assigns it as a global profile.
    switch(config)#load-balance policies
    switch(config-load-balance-policies)#load-balance sand profile myGlobalProfile
    switch(config-sand-load-balance-profile-myGlobalProfile)#hash seed 20
    switch(config)#port-channel load-balance sand profile myGlobalProfile
  • This command assigns a named load-balancing profile to a linecard.
    switch(config)#port-channel load-balance module 3-7 sand profile Linecard5
    switch(config)#
  • This command unassigns a named load-balancing profile to a linecard.
    switch(config)#no port-channel load-balance module 3-7 sand profile Linecard5
    switch(config)#

Load Balance Hash Algorithms on 7050 Series Switches

Three commands configure the load balance hash algorithm on 7050 Series switches:
  • port-channel load-balance trident fields ip controls the hash algorithm for IP packets by specifying the algorithm’s use of IP and MAC header fields. Fields that the command can specify include source and destination IP addresses, source and destination port fields (for TCP and UDP packets), and fields specified by the port-channel load-balance trident fields mac command.
  • port-channel load-balance trident fields ipv6 controls the hash algorithm for IPv6 packets by specifying the algorithm’s use of IP and MAC header fields. Fields that the command can specify include source and destination IP addresses, source and destination port fields (for TCP and UDP packets), and fields specified by the port-channel load-balance trident fields mac command.
  • port-channel load-balance trident fields mac controls the hash algorithm for non-IP packets b specifying the algorithm’s use of MAC header fields. Fields that the command can specify include the MAC source address, MAC destination address, and Ethernet type fields.
Example:
These commands configure the switch’s port channel load balance for non IP packets by using the MAC destination and Ethernet type fields in the hashing algorithm.
switch(config)#port-channel load-balance trident fields mac dst-mac eth-type
switch(config)#

Load Balance Hash Algorithms on 7150 Series Switches

Load balance profiles specify parameters used by hashing algorithms that distribute traffic across ports comprising a port channel or among component ECMP routes. The switch supports 16 load balance profiles, including the default profile. The default load balance profile is configured through port-channel load-balance fm6000 fields ip and port-channel load-balance fm6000 fields mac commands.

Load Balance Profiles

Load balance profiles are managed in load-balance-policies configuration mode. load-balance-policies configuration mode provides commands that display the contents of all configured profiles and place the switch in load-balance-profile command. Load balance profiles are created by entering load-balance-profile mode and edited while in that mode.

The load-balance policies command places the switch in load-balance-policies configuration mode. Load balance profiles specify the inputs used by the hashing algorithms that distribute traffic across ports comprising a port channel or among ECMP routes.

Examples:
  • This command places the switch in load-balance-policies configuration mode.
    switch(config)#load-balance policies
    switch(config-load-balance-policies)#
  • This command displays the contents of the four load balance profiles configured on the switch.
    switch(config-load-balance-policies)#show active
    
    load-balance policies
     load-balance fm6000 profile F-01
    port-channel hash-seed 22
    fields ip dscp
    distribution random port-channel
     !
     load-balance fm6000 profile F-02
    fields ip protocol dst-ip
    distribution random port-channel
     !
     load-balance fm6000 profile F-03
    fields ip protocol dst-ip
    fields mac dst-mac eth-type
    distribution random ecmp port-channel
     !
     load-balance fm6000 profile F-04
    
    switch(config-load-balance-policies)#
Creating a Load Balance Profile

The load-balance fm6000 profile command places the switch in load-balance-profile configuration mode to configure a specified load balance profile. The command specifies the name of the profile that subsequent commands modify. It creates a profile if the profile it references does not exist.

Example:
These commands enter load-balance-profile configuration mode, creates the LB-5 profile, and lists the default settings for the profile.
switch(config)#load-balance policies
switch(config-load-balance-policies)#load-balance fm6000 profile LB-5
switch(config-load-balance-profile-LB-5)#show active all

load-balance policies
 load-balance fm6000 profile LB-5
port-channel hash-seed 0
fields mac dst-mac src-mac eth-type vlan-priority vlan-id
fields ip protocol dst-ip dst-port src-ip src-port dscp
no distribution symmetric-hash
no distribution random

switch(config-load-balance-profile-LB-5)#
Configuring a Load Balance Profile

These commands are available in load-balance-profile configuration mode to specify the parameters that comprise a profile.

  • The fields ip command specifies the L3/L4 data fields used by the hash algorithm defined by the configuration mode load balance profile.
  • The fields mac command specifies the L2 data fields used by the hash algorithm defined by the configuration mode load balance profile.
  • The distribution symmetric-hash command enforces traffic symmetry on data distributed by the hash algorithm defined by the configuration mode load balance profile. Symmetric traffic is the flow of both directions of a data stream across the same physical link.
  • The distribution random command specifies the random distribution of data packets handled by the hash algorithm defined by the configuration mode load balance profile.
Example:
These commands configure the following components of the hash algorithm defined by the LB-7 load balance profile:
  • L2 header fields: MAC destination address, VLAN priority.
  • L3/L4 header fields: Source IP address, protocol field.
  • Symmetric hash distribution of IP and non-IP packets.
    switch(config)#load-balance policies
    switch(config-load-balance-policies)#load-balance fm6000 profile LB-7
    switch(config-load-balance-profile-LB-7)#fields ip src-ip protocol
    switch(config-load-balance-profile-LB-7)#fields mac dst-mac vlan-priority
    switch(config-load-balance-profile-LB-7)#distribution symmetric-hash mac-ip
    switch(config-load-balance-profile-LB-7)#show active
    load-balance policies
     load-balance fm6000 profile LB-7
    fields mac dst-mac vlan-priority
    fields ip protocol src-ip
    distribution symmetric-hash mac-ip
    switch(config-load-balance-profile-LB-7)#exit
    switch(config-load-balance-policies)#exit
    switch(config)#exit 
Assigning a Load Balance Profile to an Interface

The ingress load-balance profile command applies a specified load-balance profile to the configuration mode interface. Load balance profiles specify parameters used by hashing algorithms that distribute traffic across ports comprising a port channel or among ECMP routes. The switch supports 16 load balance profiles, including the default profile.

Example:
This command applies the LB-1 load balance profile to port channel interface 100.
switch(config)#interface port-channel 100
switch(config-if-Po100)#ingress load-balance profile LB-1
switch(config-if-Po100)#show active
interface Port-Channel100
 ingress load-balance profile LB-1
switch(config-if-Po100)#

Default Load Balance Profile

Two commands configure the load balance default profile on 7150 Series switches:

  • port-channel load-balance fm6000 fields ip controls the hash algorithm for IP packets by specifying the algorithm’s use of IP and MAC header fields. Fields that the command can specify include source and destination IP addresses, source and destination port fields (for TCP and UDP packets).
  • port-channel load-balance fm6000 fields mac controls the hash algorithm for non-IP packets by specifying the algorithm’s use of MAC header fields. Fields that the command can specify include include the MAC source address, MAC destination address, and Ethernet type, VLAN-ID, and VLAN-priority fields.
Examples:
  • These commands configure the load balance default profile for IP packets by using source and destination IP address fields, along with source and destination port fields for TCP, and UDP packets.
    switch(config)#port-channel load-balance fm6000 fields ip ip-tcp-udp-header
    switch(config)#
  • This command applies the default load balance profile to port channel interface 100.
    switch(config)#interface port-channel 100
    switch(config-if-Po100)#no ingress load-balance profile
    switch(config-if-Po100)#show active
    interface Port-Channel100
    switch(config-if-Po100)#

Port Channel and LACP Configuration Commands

channel-group

The channel-group command assigns the configuration mode Ethernet interfaces to a channel group, creates the group if it does not already exist, and sets the port-channel mode for the group. When adding interfaces to a previously created channel group, the port-channel mode for the newly added interfaces must match the mode for the existing group.

Channel groups are associated with a port channel interface immediately upon their creation. A command that creates a new channel group also creates a port channel with a matching ID. The port channel is configured in Port-channel Configuration Mode. Configuration changes to a port channel interface propagate to all Ethernet interfaces in the corresponding channel group. The interface port-channel command places the switch in Interface-port-channel Configuration Mode.

The no channel-group and default channel group commands remove the configuration-mode interface from the specified channel group.

Command Mode

Interface-Ethernet Configuration

Command Syntax

channel-group number mode group_mode

no channel-group

default channel-group

Parameters
  • number Specifies a channel group ID. Values range from 1 through 2000.
  • group_mode Specifies the channel-group mode for the channel group. Values include:

    • on Port channel is static and LACP is disabled on member interfaces. Port neither verifies nor negotiates port channel membership.

      • active Port channel is dynamic and member interfaces are active LACP ports that transmit and receive LACP negotiation packets.
      • passive Port channel is dynamic and member interfaces are passive LACP ports that respond to LACP negotiation packets but do not generate them.

Guidelines: Port Channels

You can configure a port channel to contain many ports, but only a subset may be active at a time. All active ports in a port channel must be compatible. Compatibility includes many factors and is platform-specific. For example, compatibility may require identical operating parameters such as speed and maximum transmission unit (MTU). Compatibility may only be possible between specific ports because of the internal organization of the switch.

Guidelines: MLAG Configurations

Static LAG is not recommended in MLAG configurations. However, these considerations apply when the channel group mode is on while configuring static MLAG:
  • When configuring multiple interfaces on the same static port channel:

    • all interfaces must physically connect to the same neighboring switch.
    • the neighboring switch must configure all interfaces into the same port channel.

The switches are misconfigured when these conditions are not met.

Disable the static port channel membership before moving any cables connected to these interfaces or changing a static port channel membership on the remote switch.

Examples:
  • These commands assign Ethernet interfaces 8 and 9 to channel group 10, and enable LACP in negotiating mode.
    switch(config)#interface ethernet 8-9
    switch(config-if-Et8-9)#channel-group 10 mode active
    switch(config-if-Et8-9)#show active
    interface Ethernet8
     channel-group 10 mode active
    interface Ethernet9
     channel-group 10 mode active
    switch(config-if-Et8-9)#
  • These commands assign Ethernet interfaces 12 and 13 to static channel group 11. LACP is disabled on these interfaces.
    switch(config)#interface ethernet 12-13
    switch(config-if-Et12-13)#channel-group 11 mode on
    switch(config-if-Et12-13)#show active
    interface Ethernet12
     channel-group 11 mode on
    interface Ethernet13
     channel-group 11 mode on
    switch(config-if-Et12-13)#

distribution random

The distribution random command specifies the random distribution of data packets handled by the hash algorithm defined by the configuration mode load balance profile. All data fields and hash seeds that are configured for the profile are used as seeds for the random number generator that defines the distribution of individual packets.

Command options allow for the random distribution of traffic across port channel links and ECMP routes. Random distribution can be enabled for either, both, or neither.

The no distribution random and default distribution random commands remove random distribution on the configuration mode load balance profile by deleting the corresponding distribution random command from the configuration.

Command Mode

Load-balance-profile Configuration

Command Syntax

distribution random BALANCE_TYPE

no distribution random

default distribution random

Parameters
  • SCOPE Specifies use of random distribution for port channels and ECMP routes. Options include:

    • <no parameter> Random distribution is enabled for ECMP routes and port channel links.
    • ecmp Random distribution is enabled for ECMP routes.
    • port-channel Random distribution is enabled for port channel links.
    • ecmp port-channel Random distribution is enabled for ECMP routes and port channel links.
    • port-channel ecmp Random distribution is enabled for ECMP routes and port channel links.

Guidelines

The distribution random command takes precedence over the distribution symmetric-hash command when both methods are simultaneously enabled.

Related Commands

Example:
These commands configure symmetric hashing on all traffic distributed through the algorithm defined by the LB-1 load balance profile.
switch(config)#load-balance policies
switch(config-load-balance-policies)#load-balance fm6000 profile LB-1
switch(config-load-balance-profile-LB-1)#distribution random ecmp port-channel
switch(config-load-balance-profile-LB-1)#show active
load-balance policies
 load-balance fm6000 profile LB-1
distribution random ecmp port-channel
switch(config-load-balance-profile-LB-1)#

distribution symmetric-hash

The distribution symmetric-hash command enforces traffic symmetry on data distributed by the hash algorithm defined by the configuration mode load balance profile. Symmetric traffic is the flow of both directions of a data stream across the same physical link.

Two symmetric-hash options specify the traffic upon which symmetry is enforced:

  • distribution symmetric-hash mac specifies that only non-IP traffic is hashed symmetrically. IP traffic is hashed normally without regard to symmetry.
  • distribution symmetric-hash mac-ip specifies that all traffic is hashed symmetrically.

The no distribution symmetric-hash and default distribution symmetric-hash commands remove the specified hashing symmetry restriction on the configuration mode load balance profile by deleting the corresponding distribution symmetric-hash command from running-config.

Command Mode

Load-balance-profile Configuration

Command Syntax

distribution symmetric-hash FIELD_TYPE

no distribution symmetric-hash

default distribution symmetric-hash

Parameters
  • FIELD_TYPE Fields the hashing algorithm uses for Layer 3 routing. Options include:

    • mac Non-IP traffic is hashed symmetrically.
    • mac-ip All traffic is hashed symmetrically.

Guidelines

The distribution random command takes precedence over the distribution symmetric-hash command when both methods are simultaneously enabled.

Related Commands
Example:
These commands configure symmetric hashing on all traffic distributed through the algorithm defined by the LB-1 load balance profile.
switch(config)#load-balance policies
switch(config-load-balance-policies)#load-balance fm6000 profile LB-1
switch(config-load-balance-profile-LB-1)#distribution symmetric-hash mac-ip
switch(config-load-balance-profile-LB-1)#show active
load-balance policies
 load-balance fm6000 profile LB-1
distribution symmetric-hash mac-ip
switch(config-load-balance-profile-LB-1)#

fields ip

The fields ip command specifies the L3/L4 data fields used by the hash algorithm defined by the configuration mode load balance profile. When a load balance profile is assigned to a port channel or Ethernet interface, its associated hash algorithm determines the distribution of packets that ingress the interface. Profile algorithms can load balance packets across port channel links or ECMP routes.

The switch calculates a hash value by using the packet header fields to balance packets across links. The hash value determines the link through which the packet is transmitted. This method also ensures that all packets in a flow follow the same network path. Packet flow is modified by changing the inputs to the port channel hash algorithm.

In network topologies that include MLAGs, programming all switches to perform the same hash calculation increases the risk of hash polarization, which leads to uneven load distribution among LAG and MLAG member links in MLAG switches. This problem is avoided by performing different hash calculations between the MLAG switch, and a non-peer switch connected to it.

The no fields ip configures the algorithm not to use L3/L4 data fields. The default fields ip command restores the default data L3/L4 fields to the load balancing algorithm defined by the configuration mode profile by removing the corresponding fields ip or no fields ip command from running-config.

Command Mode

Load-balance-profile Configuration

Command Syntax

fields ip IP_FIELD

no fields ip

default fields ip

Parameters
  • IP_FIELD Specifies the L3/L4 fields the hashing algorithm uses. Options include:

    • dscp Algorithm uses dscp field.
    • dst-ip Algorithm uses destination IP address field.
    • dst-port Algorithm uses destination TCP/UDP port field.
    • protocol Algorithm uses protocol field.
    • src-ip Algorithm uses source IP address field.
    • src-port Algorithm uses source TCP/UDP port field.

Command may include from one to six fields, in any combination and listed in any order. The default setting is the selection of all fields.

Related Commands

Example:
These commands specify the IP source and protocol fields as components of the hash algorithm defined by the LB-1 load balance profile.
switch(config)#load-balance policies
switch(config-load-balance-policies)#load-balance fm6000 profile LB-1
switch(config-load-balance-profile-LB-1)#fields ip src-ip protocol
switch(config-load-balance-profile-LB-1)#show active
load-balance policies
 load-balance fm6000 profile LB-1
fields ip protocol src-ip
switch(config-load-balance-profile-LB-1)#

fields mac

The fields mac command specifies the L2 data fields used by the hash algorithm defined by the configuration mode load balance profile. When a load balance profile is assigned to a port channel or Ethernet interface, its associated hash algorithm determines the distribution of packets that ingress the interface. Profile algorithms can load balance packets across port channel links or ECMP routes.

The switch calculates a hash value using the packet header fields to balance packets across links. The hash value determines the link through which the packet is transmitted. This method also ensures that all packets in a flow follow the same network path. Packet flow is modified by changing the inputs to the port channel hash algorithm.

In network topologies that include MLAGs, programming all switches to perform the same hash calculation increases the risk of hash polarization, which leads to uneven load distribution among LAG and MLAG member links in MLAG switches. This problem is avoided by performing different hash calculations between the MLAG switch, and a non-peer switch connected to it.

The no fields mac configures the algorithm not to use L2 data fields. The default fields mac command restores the default data L2 fields to the load balancing algorithm defined by the configuration mode profile by removing the corresponding fields mac or no fields mac command from running-config.

Command Mode

Load-balance-profile Configuration

Command Syntax

fields mac MAC_FIELD

no fields mac

default fields mac

Parameters
  • MAC_FIELD Specifies the L2 fields the hashing algorithm uses. Options include:

    • dst-mac Algorithm uses MAC destination field.
    • eth-type Algorithm uses MAC destination field.
    • src-mac Algorithm uses MAC source field.
    • vlan-id Algorithm uses VLAN ID field.
    • vlan-priority Algorithm uses VLAN priority field.

Related Commands

load-balance fm6000 profile places the switch in load-balance-profile configuration mode.

Example:
These commands specify the MAC destination and VLAN priority fields as components of the hash algorithm defined by the LB-1 load balance profile.
switch(config)#load-balance policies
switch(config-load-balance-policies)#load-balance fm6000 profile LB-1
switch(config-load-balance-profile-LB-1)#fields mac dst-mac vlan-priority
switch(config-load-balance-profile-LB-1)#show active
load-balance policies
 load-balance fm6000 profile LB-1
fields mac dst-mac vlan-priority
switch(config-load-balance-profile-LB-1)#

hash-seed

The hash-seed command specifies the seed used by the hash algorithm defined by the configuration mode load balance profile. Profile algorithms can load balance packets across port channel links or ECMP routes.

The no hash-seed and default hash-seed commands restore the default hash seed value of 0 to the load balancing algorithm defined by the configuration mode profile by removing the corresponding hash-seed command from running-config.

Command Mode

Load-balance-profile Configuration

Command Syntax

hash-seed number

no hash-seed number

default hash-seed number

Parameters
  • number Specifies the value of the hash seed. Value ranges from 0 to 39.

Example:
These commands configure the hash seed 20 in a profile and assign it as the global profile.
switch(config)#load-balance policies
switch(config-load-balance-policies)#load-balance sand profile myGlobalProfile
switch(config-sand-load-balance-profile-myGlobalProfile)#hash-seed 20
switch(config)#port-channel load-balance sand profile myGlobalProfile

ingress load-balance profile

The ingress load-balance profile command applies the specified load-balance profile to the configuration mode interface. Load balance profiles specify parameters used by hashing algorithms that distribute traffic across ports comprising a port channel or among ECMP routes. The switch supports 16 load balance profiles, including the default profile.

Load balance profiles can be assigned to Ethernet and port channel interfaces. Profiles define the distribution method of traffic that ingresses the interface among the ports comprising a port channel or routes comprising an ECMP.

The default load balance profile is configured through port-channel load-balance fm6000 fields ip and port-channel load-balance fm6000 fields mac commands.

The no ingress load-balance profile and default ingress load-balance profile commands restore the default load balance profile for the configuration mode interface by removing the corresponding ingress load-balance profile command from running-config.

Command Mode

Interface-Ethernet Configuration

Interface-Port-Channel Configuration

Command Syntax

ingress load-balance profile profile_name

no ingress load-balance profile

default ingress load-balance profile

Parameters
  • profile_name Name of profile assigned to interface.

Example:
This command applies the LB-1 load balance profile to port channel interface 100.
switch(config)#interface port-channel 100
switch(config-if-Po100)#show active
interface Port-Channel100

switch(config-if-Po100)#ingress load-balance profile LB-1
switch(config-if-Po100)#
interface Port-Channel100
 ingress load-balance profile LB-1

switch(config-if-Po100)#

interface port-channel

The interface port-channel command places the switch in port-channel interface configuration mode for modifying parameters of specified link aggregation (LAG) interfaces. When entering configuration mode to modify existing port channel interfaces, the command can specify multiple interfaces.

The command creates a port channel interface if the specified interface does not exist prior to issuing the command. When creating an interface, the command can only specify a single interface.

The no interface port-channel and default interface port-channel commands delete the specified LAG interfaces from running-config.

Command Mode

Global Configuration

Command Syntax

interface port-channel p_range

no interface port-channel p_range

default interface port-channel p_range

Parameter
  • p_range Port channel interfaces (number, range, or comma-delimited list of numbers and ranges).

Port channel numbers range from 1 to 2000.

Guidelines

When configuring a port channel, you do not need to issue the interface port-channel command before assigning a port to the port channel (see the channel-groupcommand). The port channel number is implicitly created when a port is added to the specified port channel with the channel-group number command.

To display ports that are members of a port channel, enter show port-channel. To view information about hardware limitations for a port channel, enter show port-channel limits.

All active ports in a port channel must be compatible. Compatibility comprises many factors and is specific to a given platform. For example, compatibility may require identical operating parameters such as speed and/or maximum transmission unit (MTU). Compatibility may only be possible between specific ports because of internal organization of the switch.

You can configure a port channel with a set of ports such that more than one subset of the member ports are mutually compatible. Port channels in EOS are designed to activate the compatible subset of ports with the largest aggregate capacity. A subset with two 40 Gbps ports (aggregate capacity 80 Gbps) has preference to a subset with five active 10 Gbps ports (aggregate capacity 50 Gbps).

Example:
This example creates port channel interface 3:
switch(config)#interface port-channel 3
switch(config-if-Po3)#

lacp port-priority

The lacp port-priority command sets the aggregating port priority for the configuration mode interface. Priority is supported on port channels with LACP-enabled physical interfaces. LACP port priority determines the port that is active in a LAG in fallback mode. Numerically lower values have higher priority.

Each port in an aggregation is assigned a 32-bit port identifier by prepending the port priority (16 bits) to the port number (16 bits). Port priority determines the ports that are placed in standby mode when hardware limitations prevent a single aggregation of all compatible ports.

Priority numbers range from 0 to 65535. The default is 32768. Interfaces with higher priority numbers are placed in standby mode before interfaces with lower priority numbers.

The no lacp port-priority and default lacp port-priority commands restore the default port-priority to the configuration mode interface by removing the corresponding lacp port-priority command from running-config.

Command Mode

Interface-Ethernet Configuration

Command Syntax

lacp port-priority priority_value

no lacp port-priority

default lacp port-priority

Parameters
  • priority_level Port priority. Values range from 0 to 65535. Default is 32768

Example:
These commands assign the port priority of 4096 to Ethernet interface 8.
switch(config)#interface ethernet 8
switch(config-if-Et8)#lacp port-priority 4096
switch(config-if-Et8)#show active
interface Ethernet8
 lacp port-priority 4096
switch(config-if-Et8)#

lacp system-priority

The lacp system-priority command configures the switch’s LACP system priority. Values range between 0 and 65535. Default value is 32768.

Each switch is assigned a globally unique 64-bit system identifier by prepending the system priority (16 bits) to the MAC address of one of its physical ports (48 bits). Peer devices use the system identifier when forming an aggregation to verify that all links are from the same switch. The system identifier is also used when dynamically changing aggregation capabilities resulting from LACP data; the system with the numerically lower system identifier can dynamically change advertised aggregation parameters.

The no lacp system-priority and default lacp system-priority commands restore the default system priority by removing the lacp system-priority command from running-config.

Command Mode

Global Configuration

Command Syntax

lacp system-priority priority_value

no lacp system-priority

default lacp system-priority

Parameters
  • priority_value System priority number. Values range from 0 to 65535. Default is 32768.

Example:
This command assigns the system priority of 8192 to the switch.
switch(config)#lacp system-priority 8192
switch(config)#

lacp timer

The lacp timer command configures the LACP reception interval on the configuration mode interface. The LACP timeout specifies the reception rate of LACP packets at interfaces supporting LACP. Supported rates include:

  • normal: 30 seconds with synchronized interfaces; one second while interfaces are synchronizing.
  • fast: one second.

This command is supported on LACP-enabled interfaces. The default value is normal.

The no lacp timer and default lacp timer commands restore the default value of normal on the configuration mode interface by deleting the corresponding lacp timer command from running-config.

Command Mode

Interface-Ethernet Configuration

Command Syntax

lacp timer RATE_LEVEL

no lacp timer

default lacp timer

Parameters
  • RATE_LEVEL LACP reception interval. Options include:

    • fast One second.
    • normal 30 seconds for synchronized interfaces; one second while interfaces synchronize.

Example:
This command sets the LACP timer to one second on Ethernet interface 4.
switch(config-if-Et4)#lacp timer fast
switch(config-if-Et4)#

load-balance fm6000 profile

The load-balance fm6000 profile command places the switch in load-balance-profile configuration mode to configure a specified load balance profile. The command specifies the name of the profile that subsequent commands modify. It creates a profile if the profile it references does not exist.

Load balance profiles specify parameters used by hashing algorithms that distribute traffic across ports comprising a port channel or among component ECMP routes. The switch supports 16 load balance profiles, including the default profile. The default load balance profile is configured through port-channel load-balance fm6000 fields ip and port-channel load-balance fm6000 fields mac commands.

The load balance profile name is referenced when it is applied to an interface. The default profile is not associated with a name and is applied to an interface in the absence of a named profile assignment.

The no load-balance fm6000 profile and default load-balance fm6000 profile commands delete the specified load balance profile from running-config. Profiles that are assigned to an interface cannot be deleted. Attempts to delete an assigned profile generate a profile in use error messages.

The load-balance fm6000 profile command is accessible from load-balance-policies configuration mode. Load-balance-profile configuration mode is not a group change mode; running-config is changed immediately upon entering commands. Exiting load-balance-policies configuration mode does not affect the configuration. The exit command returns the switch to load-balance-policies configuration mode.

Command Mode

Load-balance-policies Configuration

Command Syntax

load-balance fm6000 profile profile_name

no load-balance fm6000 profile profile_name

default load-balance fm6000 profile profile_name

Parameters
  • profile_name Name of the load-balance profile.

Commands Available in Load-balance-profile Configuration Mode
Related Commands
Example:
These commands enter load-balance-profile configuration mode, creates the LB-1 profile, and lists the default settings for the profile.
switch(config)#load-balance policies
switch(config-load-balance-policies)#load-balance fm6000 profile LB-1
switch(config-load-balance-profile-LB-1)#show active all
load-balance policies
 load-balance fm6000 profile LB-1
port-channel hash-seed 0
fields mac dst-mac src-mac eth-type vlan-priority vlan-id
fields ip protocol dst-ip dst-port src-ip src-port dscp
no distribution symmetric-hash
no distribution random
switch(config-load-balance-profile-LB-1)#

load-balance policies

The load-balance policies command places the switch in load-balance-policies configuration mode. Load-balance-policies configuration mode provides commands for managing load-balance profiles. Load balance profiles specify the inputs used by the hashing algorithms that distribute traffic across ports comprising a port channel or among ECMP routes.

The no load-balance policies and default load-balance policies commands delete all load balance profiles from running-config. The command generates an error message when at least one profile is assigned to an interface.

Load-balance-policies configuration mode is not a group change mode; running-config is changed immediately upon entering commands. Exiting load-balance-policies configuration mode does not affect running-config. The exit command returns the switch to global configuration mode.

Command Mode

Global Configuration

Command Syntax

load-balance policies

no load-balance policies

default load-balance policies

Commands Available in Load-balance-policies Configuration Mode
  • load-balance fm6000 profile places the switch in load-balance-profile configuration mode.
  • show active displays contents of all load balance profiles.
Related Commands
Examples:
  • This command places the switch in load-balance-policies configuration mode.
    switch(config)#load-balance policies
    switch(config-load-balance-policies)#
  • This command displays the contents of the three configured load balance profiles.
    switch(config-load-balance-policies)#show active
    
    load-balance policies
     load-balance fm6000 profile F-01
    port-channel hash-seed 22
    fields ip dscp
    distribution random port-channel
     !
     load-balance fm6000 profile F-02
    fields ip protocol dst-ip
    fields mac dst-mac eth-type
    distribution random ecmp port-channel
     !
     load-balance fm6000 profile F-03
    
    switch(config-load-balance-policies)#

load-balance sand profile (7500E/7500R)

The load-balance sand profile command configures a load-balance profile on a sand module switch. A default profile is designated as a global profile when no other profile is set as global profile. Note, a warning message is displayed when a profile is entered or deleted.

If no load-balance sand profile command is executed when the profile set is default then the following warning message is displayed:
! profile default is a reserved profile and cannot be deleted

Command Mode

Global Configuration

Command Syntax

load-balance sand profile profile_name

no load-balance sand profile profile_name

Parameter

profile_name Name of the profile assigned to the selected module.

Examples:
  • These commands designate a default profile as a global profile on sand module platform switch. Note, a warning message is displayed when a profile is entered or deleted.
    switch(config)#load-balance policies
    switch(config-load-balance-policies)#load-balance sand profile default
     ! profile default is a reserved profile
    ! profile default is the current global profile
  • When no form of the command is executed it displays the following warning message.
    switch(config)#load-balance policies
    switch(config-load-balance-policies)#no load-balance sand profile default
    ! profile default is a reserved profile and cannot be deleted

port-channel hash-seed

The port-channel hash-seed command specifies the seed used by the hash algorithm defined by the configuration mode load balance profile when distributing the load across ports comprising a port channel. When a load balance profile is assigned to a port channel or Ethernet interface, its associated hash algorithm determines the distribution of packets that ingress the interface. Profile algorithms can load balance packets across port channel links or ECMP routes.

The hash seed that the algorithm uses to select port channel links or ECMP routes is configured by the ip load-sharing command.

The no port-channel hash-seed and default port-channel hash-seed commands restore the default hash seed value of 0 to the load balancing algorithm defined by the configuration mode profile by removing the corresponding port-channel hash-seed command from running-config.

Command Mode

Load-balance-profile Configuration

Command Syntax

port-channel hash-seed number

no port-channel hash-seed

default port-channel hash-seed

Parameters
  • number The hash seed. Value ranges from 0 to 39.
Related Commands
Example:
Thes commands configure the port-channel hash seed of 22 for the hash algorithm defined by the LB-1 load balance profile.
switch(config)#load-balance policies
switch(config-load-balance-policies)#load-balance fm6000 profile LB-1
switch(config-load-balance-profile-LB-1)#port-channel hash-seed 22
switch(config-load-balance-profile-LB-1)#show active
load-balance policies
 load-balance fm6000 profile LB-1
port-channel hash-seed 22
switch(config-load-balance-profile-LB-1)#

port-channel lacp fallback timeout

The port-channel lacp fallback timeout command specifies the fallback timeout period for the configuration mode interface.

Fallback timeout settings persist in running-config without taking effect for interfaces that are not configured into fallback mode. The default fallback timeout period is 90 seconds.

The no port-channel lacp fallback timeout and default port-channel lacp fallback timeout commands restore the default fallback timeout of 90 seconds for the configuration mode interface by removing the corresponding port-channel lacp fallback timeout command from running-config.

Command Mode

Interface-Port-Channel Configuration

Command Syntax

port-channel lacp fallback timeout period

no port-channel lacp fallback timeout

default port-channel lacp fallback timeout

Parameters
  • periodMaximum interval between receipt of LACP PDU packets (seconds). Value ranges from 1 to 300 seconds. Default value is 90.

Related Commands

port-channel lacp fallback configures fallback mode for a port channel interface.

Guidelines

The fallback timeout period should not be shorter than the LACP reception interval (lacp timer). The default LACP reception interval is 30 seconds.

Example:
This command enables LACP fallback mode, then configures an LACP fallback timeout of 100 seconds on port channel interface 13.
switch(config)#interface port-channel 13
switch(config-if-Po13)#port-channel lacp fallback
switch(config-if-Po13)#port-channel lacp fallback timeout 100
switch(config-if-Po13)#show active
interface Port-Channel13
 port-channel lacp fallback
 port-channel lacp fallback timeout 100
switch(config-if-Po13)#

port-channel lacp fallback

The port-channel lacp fallback command enables the LACP fallback mode on the interface.

LACP fallback is unconfigured and disabled by default. An LACP interface without fallback enabled does not form a LAG until it receives PDUs from its peer.

LACP fallback can be configured on an interface in static or individual mode:

  • static mode The port channel member with the lowest LACP port priority is active and maintains contact with the peer (sending and receiving data) while other port channel members remain in standby mode until a LACP PDU is received. All members continue to send (and can receive) LACP PDUs.

    • individual mode All port channel members act as individual ports, reverting to their port-specific configuration while the channel is in fallback mode, and continue to send and receive data. All members continue to send LACP PDUs until a LACP PDU is received by one of the member ports.

The no port-channel lacp fallback and default port-channel lacp fallback commands disable LACP fallback mode on the configuration mode interface by removing the corresponding port-channel lacp fallback command from running-config.

Command Mode

Interface-Port-Channel Configuration

Command Syntax

port-channel lacp fallback [MODE]

no port-channel lacp fallback

default port-channel lacp fallback

Parameters
  • MODE LACP fallback mode. Options include:

    • <no parameter> Enables static LACP fallback mode.

      • static Enables static LACP fallback mode.
      • individual Eenables individual LACP fallback mode.

Related Commands
Examples:
  • These commands enable LACP static fallback mode, then configure an LACP fallback timeout of 100 seconds on port channel interface 13. If LACP negotiation fails, only the member port with the lowest LACP priority will remain active until an LACP PDU is received by one of the member ports.
    switch(config)#interface port-channel 13
    switch(config-if-Po13)#port-channel lacp fallback static
    switch(config-if-Po13)#port-channel lacp fallback timeout 100
    switch(config-if-Po13)#show active
    interface Port-Channel13
     port-channel lacp fallback static
     port-channel lacp fallback timeout 100
    switch(config-if-Po13)#
  • These commands enable LACP individual fallback mode, then configure an LACP fallback timeout of 50 seconds on port channel interface 17. If LACP negotiation fails, all member ports will act as individual switch ports, using port-specific configuration, until a LACP PDU is received by one of the member ports.
    switch(config)#interface port-channel 17
    switch(config-if-Po17)#port-channel lacp fallback individual
    switch(config-if-Po17)#port-channel lacp fallback timeout 50
    switch(config-if-Po17)#show active
    interface Port-Channel17
     port-channel lacp fallback individual
     port-channel lacp fallback timeout 50
    switch(config-if-Po17)#

port-channel load-balance arad fields ip

The port-channel load-balance arad fields ip command specifies the data fields that the port channel load balance hash algorithm uses for distributing IP packets on Arad platform switches. The hashing algorithm fields used for IP packets differ from the fields used for non-IP packets.

The switch calculates a hash value using the packet header fields to load balance packets across links in a port channel. The hash value determines the link through which the packet is transmitted. This method also ensures that all packets in a flow follow the same network path. Packet flow is modified by changing the inputs to the port channel hash algorithm.

In network topologies that include MLAGs, programming all switches to perform the same hash calculation increases the risk of hash polarization, which leads to uneven load distribution among LAG and MLAG member links in MLAG switches. This problem is avoided by performing different hash calculations between the MLAG switch, and a non-peer switch connected to it.

The no port-channel load-balance arad fields ip and default port-channel load-balance arad fields ip commands restore the default data fields for the IP packet load balancing algorithm by removing the port-channel load-balance arad A fields ip command from running-config.

Command Mode

Global Configuration

Command Syntax

port-channel load-balance arad fields ip IP_FIELD_NAME

no port-channel load-balance arad fields ip

default port-channel load-balance arad fields ip

Parameters
  • IP_FIELD_NAME Fields the hashing algorithm uses for Layer 3 routing. Options include:

    • ip-tcp-udp-header Algorithm uses source and destination IP address fields. Source and destination port fields are included for TCP and UDP packets.

      • mac-header Algorithm uses entire MAC header.

    A command can only specify one option. The default setting is ip-tcp-udp-header.

Guidelines

The port channel hash algorithm for non-IP packets is not configurable and always includes the entire MAC header.

Related Commands
Example:
These commands configure the switch’s port channel load balance hash algorithm for IP packets to use source and destination IP address (and port) fields.
switch(config)#port-channel load-balance fm6000 fields ip ip-tcp-udp-header
switch(config)#

port-channel load-balance fm6000 fields ip

The port-channel load-balance fm6000 fields ip command specifies the data fields that the port channel load balance hash algorithm uses for distributing IP packets on FM6000 platform switches. The hashing algorithm fields used for IP packets differ from the fields used for non-IP packets.

The switch calculates a hash value using the packet header fields to load balance packets across links in a port channel. The hash value determines the link through which the packet is transmitted. This method also ensures that all packets in a flow follow the same network path. Packet flow is modified by changing the inputs to the port channel hash algorithm.

In network topologies that include MLAGs, programming all switches to perform the same hash calculation increases the risk of hash polarization, which leads to uneven load distribution among LAG and MLAG member links in MLAG switches. This problem is avoided by performing different hash calculations between the MLAG switch, and a non-peer switch connected to it.

The no port-channel load-balance fm6000 fields ip and default port-channel load-balance fm6000 fields ip commands restore the default data fields for the IP packet load balancing algorithm by removing the port-channel load-balance fm6000 fields ip command from running-config.

Command Mode

Global Configuration

Command Syntax

port-channel load-balance fm6000 fields ip IP_FIELD_NAME

no port-channel load-balance fm6000 fields ip

default port-channel load-balance fm6000 fields ip

Parameters
  • IP_FIELD_NAME Specifies fields the hashing algorithm uses for layer 3 routing. Options include:

    • ip-tcp-udp-header Algorithm uses source and destination IP address fields. Source and destination port fields are included for TCP and UDP packets.

A command can only specify one option. The default setting is ip-tcp-udp-header.

Related Commands
Example:
These commands configure the switch’s port channel load balance for IP packets by source and destination IP address and port fields.
switch(config)#port-channel load-balance fm6000 fields ip ip-tcp-udp-header
switch(config)#

port-channel load-balance fm6000 fields mac

The port-channel load-balance fm6000 fields mac command specifies data fields that configure the port channel load balance hash algorithm for non-IP packets on FM6000 platform switches. The hashing algorithm fields used for balancing non-IP packets differ from the fields used for IP packets.

The switch calculates a hash value using the packet header fields to load balance packets across links in a port channel. The hash value determines the link through which the packet is transmitted. This method also ensures that all packets in a flow follow the same network path. Packet flow is modified by changing the inputs to the port channel hash algorithm.

In network topologies that include MLAGs, programming all switches to perform the same hash calculation increases the risk of hash polarization, which leads to uneven load distribution among LAG and MLAG member links in MLAG switches. This problem is avoided by performing different hash calculations between the MLAG switch, and a non-peer switch connected to it.

The no port-channel load-balance fm6000 fields mac and default port-channel load-balance fm6000 fields mac commands restore the default data fields for the non-IP packet load balancing algorithm by removing the port-channel load-balance fm6000 fields mac command from running-config.

Command Mode

Global Configuration

Command Syntax

port-channel load-balance fm6000 fields mac MAC_FIELD_NAME

no port-channel load-balance fm6000 fields mac

default port-channel load-balance fm6000 fields mac

Parameters
  • MAC_FIELD_NAMEFields the hashing algorithm uses for Layer 2 routing. Options include:
    • dst-mac MAC destination field.
    • eth-typeEtherType field.
    • src-macMAC source field.
    • vlan-idVLAN ID field.
    • vlan-priorityVLAN priority field.

Command may include from one to five fields, in any combination and listed in any order. The default setting is the selection of all fields.

Related Commands
Example:
These commands configure the switch’s port channel load balance for non-IP packets by using the MAC destination and Ethernet type fields in the hashing algorithm.
switch(config)#port-channel load-balance fm6000 fields mac dst-mac eth-type 
switch(config)#

port-channel load-balance module

The port-channel load-balance module command assigns a named load-balancing profile to a linecard.

Note: Available on the 7500E platform.

The no port-channel load-balance module and default port-channel load-balance module commands unassigns the load balancing module, or restores the default data fields for the load balancing module.

Command Mode

Global Configuration

Command Syntax

port-channel load-balance module LINECARD_RANGE sand profile PROFILE_NAME

no port-channel load-balance module LINECARD_RANGE sand profile PROFILE_NAME

default port-channel load-balance module LINECARD_RANGE sand profile PROFILE_NAME

Parameters
  • LINECARD_RANGE Linecard number range includes:
    • <3-10>Linecard number range.
  • PROFILE_NAMELoad-balance profile name.
Examples:
  • This command assigns a named load-balancing profile to a linecard.
    switch(config)#port-channel load-balance module 3-7 sand profile Linecard5
    switch(config)#
  • This command unassigns a named load-balancing profile to a linecard.
    switch(config)#no port-channel load-balance module 3-7 sand profile Linecard5
    switch(config)#

port-channel load-balance petraA fields ip

The port-channel load-balance petraA fields ip command specifies the data fields that the port channel load balance hash algorithm uses for distributing IP packets on Petra platform switches. The hashing algorithm fields used for IP packets differ from the fields used for non-IP packets.

The switch calculates a hash value using the packet header fields to load balance packets across links in a port channel. The hash value determines the link through which the packet is transmitted. This method also ensures that all packets in a flow follow the same network path. Packet flow is modified by changing the inputs to the port channel hash algorithm.

In network topologies that include MLAGs, programming all switches to perform the same hash calculation increases the risk of hash polarization, which leads to uneven load distribution among LAG and MLAG member links in MLAG switches. This problem is avoided by performing different hash calculations between the MLAG switch, and a non-peer switch connected to it.

The no port-channel load-balance petraA fields ip and default port-channel load-balance petraA fields ip commands restore the default data fields for the IP packet load balancing algorithm by removing the port-channel load-balance petraA fields ip command from running-config.

Command Mode

Global Configuration

Command Syntax

port-channel load-balance petraA fields ip IP_FIELD_NAME

no port-channel load-balance petraA fields ip

default port-channel load-balance petraA fields ip

Parameters
  • IP_FIELD_NAMEFields the hashing algorithm uses for Layer 3 routing. Options include:
    • ip-tcp-udp-header Algorithm uses source and destination IP address fields. Source and destination port fields are included for TCP and UDP packets.
    • mac-header Algorithm uses entire MAC header.

A command can only specify one option. The default setting is ip-tcp-udp-header.

Guidelines

The port channel hash algorithm for non-IP packets is not configurable and always includes the entire MAC header.

Related Commands
Example:
These commands configure the switch’s port channel load balance hash algorithm for IP packets to use source and destination IP address (and port) fields.
switch(config)#port-channel load-balance fm6000 fields ip ip-tcp-udp-header
switch(config)#

port-channel load-balance sand profile (7500E/7500R)

The port-channel load-balance sand profile command configures a global LAG hashing profile on the port channel interface. A default profile is set as a global profile when no other profile is set as global.

The no port-channel load-balance sand profile command removes the active profile from the port-channel load-balance command from running-config, restoring the default profile.

Command Mode

Global Configuration

Command Syntax

port-channel load-balance sand profile profile_name

no port-channel load-balance sand profile profile_name

Parameter

profile_name Name of the profile assigned to the selected module.

Example:
This command configures a global LAG hashing profile on 7500 series platform switch.
switch(config)#port-channel load-balance sand profile myGlobalProfile
switch(config)#

port-channel load-balance trident fields ip

The port-channel load-balance trident fields ip command specifies the data fields that the port channel load balance hash algorithm uses for distributing IP packets on Trident platform switches. The hashing algorithm fields used for IP packets differ from the fields used for non-IP packets.

The switch calculates a hash value using the packet header fields to load balance packets across links in a port channel. The hash value determines the link through which the packet is transmitted. This method also ensures that all packets in a flow follow the same network path. Packet flow is modified by changing the inputs to the port channel hash algorithm.

In network topologies that include MLAGs, programming all switches to perform the same hash calculation increases the risk of hash polarization, which leads to uneven load distribution among LAG and MLAG member links in MLAG switches. This problem is avoided by performing different hash calculations between the MLAG switch, and a non-peer switch connected to it.

The no port-channel load-balance trident fields ip and default port-channel load-balance trident fields ip commands restore the default data fields for the IP packet load balancing algorithm by removing the port-channel load-balance trident fields ip command from running-config.

Command Mode

Global Configuration

Command Syntax

port-channel load-balance trident fields ip IP_FIELD_NAME

no port-channel load-balance trident fields ip

default port-channel load-balance trident fields ip

Parameters
  • IP_FIELD_NAMESpecifies fields the hashing algorithm uses for Layer 3 routing. Options include:
  • Command may include from one to four of the following four options, in any combination and listed in any order.
    • destination-ip Algorithm uses destination IP address field.
    • source-ip Algorithm uses source IP address field.
    • destination-port aAgorithm uses destination TCP/UDP port field.
    • source-portAlgorithm uses source TCP/UDP port field.
      • ip-tcp-udp-header Algorithm uses source and destination IP address fields. Source and destination port fields are included for TCP and UDP packets.
        Note: This option can’t be used in combination with any other option.
    • mac-header Algorithm uses fields specified by port-channel load-balance trident fields mac.
      Note: This option can’t be used in combination with any other option.

Default setting is ip-tcp-udp-header

Related Commands
Example:
These commands configure the switch’s port channel load balance for IP packets by using the IPv6 destination field in the hashing algorithm.
switch(config)#port-channel load-balance trident fields ip destination-ip
switch(config)#

port-channel load-balance trident fields ipv6

The port-channel load-balance trident fields ipv6 command specifies the data fields that the port channel load balance hash algorithm uses for distributing IPv6 packets on Trident platform switches. The hashing algorithm fields used for IPv6 packets differ from the fields used for non-IPv6 packets.

The switch calculates a hash value using the packet header fields to load balance packets across links in a port channel. The hash value determines the link through which the packet is transmitted. This method also ensures that all packets in a flow follow the same network path. Packet flow is modified by changing the inputs to the port channel hash algorithm.

In network topologies that include MLAGs, programming all switches to perform the same hash calculation increases the risk of hash polarization, which leads to uneven load distribution among LAG and MLAG member links in MLAG switches. This problem is avoided by performing different hash calculations between the MLAG switch, and a non-peer switch connected to it.

The no port-channel load-balance trident fields ipv6 and default port-channel load-balance trident fields ipv6 commands restore the default data fields for the IPv6 packet load balancing algorithm by removing the port-channel load-balance trident fields ipv6 command from running-config.

Command Mode

Global Configuration

Command Syntax

port-channel load-balance trident fields ipv6 IP_FIELD_NAME

no port-channel load-balance trident fields ipv6

default port-channel load-balance trident fields ipv6

Parameters
  • IP_FIELD_NAME Specifies fields the hashing algorithm uses for Layer 3 routing. Options include:

    Command may include from one to four of the following four options, in any combination and listed in any order.

    • destination-ipAlgorithm uses destination IPv6 address field.
    • source-ip Algorithm uses source IPv6 address field.
    • destination-port Algorithm uses destination TCP/UDP port field.
    • source-portAlgorithm uses source TCP/UDP port field.
      • ip-tcp-udp-header Algorithm uses source and destination IPv6 address fields. Source and destination port fields are included for TCP and UDP packets.
        Note: This option can’t be used in combination with any other option.
      • mac-header Algorithm uses fields specified by port-channel load-balance trident fields mac.
        Note: This option can’t be used in combination with any other option.

      Default setting is ip-tcp-udp-header

Related Commands
Example:
These commands configure the switch’s port channel load balance for IP packets by using the IPv6 source field in the hashing algorithm.
switch(config)#port-channel load-balance trident fields ipv6 source-ip
switch(config)#

port-channel load-balance trident fields mac

The port-channel load-balance trident fields mac command specifies data fields that the port channel load balance hash algorithm uses for distributing non-IP packets on Trident platform switches. The hashing algorithm fields used for non-IP packets differ from the fields used for IP packets.

The switch calculates a hash value using the packet header fields to load balance packets across links in a port channel. The hash value determines the link through which the packet is transmitted. This method also ensures that all packets in a flow follow the same network path. Packet flow is modified by changing the inputs to the port channel hash algorithm.

In network topologies that include MLAGs, programming all switches to perform the same hash calculation increases the risk of hash polarization, which leads to uneven load distribution among LAG and MLAG member links in MLAG switches. This problem is avoided by performing different hash calculations between the MLAG switch, and a non-peer switch connected to it.

The no port-channel load-balance trident fields mac and default port-channel load-balance trident fields mac commands restore the default data fields for the non-IP packet load balancing algorithm by removing the port-channel load-balance trident fields mac command from running-config.

Command Mode

Global Configuration

Command Syntax

port-channel load-balance trident fields mac MAC_FIELD_NAME

no port-channel load-balance trident fields mac

default port-channel load-balance trident fields mac

Parameters
  • MAC_FIELD_NAMEFields the hashing algorithm uses for Layer 2 routing. Options include:
    • dst-mac MAC destination field.
    • eth-type EtherType field.
    • src-mac MAC source field.

    Command may include from one to three fields, in any combination and listed in any order. The default setting is the selection of all fields.

Related Commands
Example:
These commands configure the switch’s port channel load balance for non-IP packets by using the MAC destination and Ethernet type fields in the hashing algorithm.
switch(config)#port-channel load-balance trident fields mac dst-mac eth-type
switch(config)#

port-channel load-balance

The port-channel load-balance command specifies the seed in the hashing algorithm that balances the load across ports comprising a port channel. Available seed values vary by switch platform.

The no port-channel load-balance and default port-channel load-balance commands remove the port-channel load-balance command from running-config, restoring the default hash seed value of 0.

Command Mode

Global Configuration

Command Syntax

port-channel load-balance platform {hash_seed | fields ip fields | hash hash_function }

no port-channel load-balance platform [hash_seed]

default port-channel load-balance platform [hash_seed]

Parameters
Note: Parameter options vary by switch model. Verify available options with the ? command.
  • platform ASIC switching device. Value depends on the switch model.
  • hash_seed The numerical seed for the hash function. Value range varies by switch platform:
    • arad 0 to 65535.
    • fm6000 0 to 39.
    • petraA Uses field inputs only.
    • trident 0 to 47.

    For trident platform switches, algorithms using hash seeds between 0 and 15 typically result in more effective distribution of data streams across the port channels.

  • fields Which fields will be used as inputs to the port channel hash.
    • gre Configure which GRE fields are inputs to the hash.
    • ip Configure which fields are inputs to the hash for IPv4 packets.
    • ipv6Configure which fields are inputs to the hash for IPv6 packets.
    • mac Configure which MAC fields are inputs to the hash.
    • mac-in-mac Configure which MAC-in-MAC fields are inputs to the hash.
    • mpls Configure which MPLS fields are inputs to the hash.
    • destination-ip Use the Layer 3 IP destination address in the hash.
    • destination-port Use the Layer 4 TCP/UDP destination port in the hash.
    • dst-ip Use the destination IP address in the hash.
    • dst-mac Use the destination Payload MAC in the hash (or the destination MAC address in the MAC hash).
    • eth-type Use the Ethernet type in the MAC hash.
    • ip-in-ip Use the outer IP header in the hash for IPv4 over IPv4 GRE tunnel.
    • ip-in-ipv6 Use the outer IP header in the hash for IPv4 over IPv6 GRE tunnel.
    • ipv6-in-ip Use the outer IP header in the hash for IPv6 over IPv4 GRE tunnel.
    • ipv6-in-ipv6 Use the outer IP header in the hash for IPv6 over IPv6 GRE tunnel.
    • ip-tcp-udp-header Use the Layer 3 and Layer 4 hashes.
    • isidUse the MAC-in-MAC ISID in the hash.
    • label Use the MPLS label in the hash.
    • mac-header Use the MAC hash.
    • outer-mac Use the outer MAC of source and destination in the hash.
    • source-ip Use the Layer 3 IP source address in the hash.
    • src-ip Use the source IP address in the hash.
    • source-port Use l\Layer 4 TCP/UDP source port in the hash.
    • src-mac Use the source payload MAC in the hash (or the source MAC address in the MAC hash).
  • hash_function Specifies the hash polynomial function. Values range from 0-2.
Example:
This command configures a hash seed of 10 on an FM6000 platform switch.
switch(config)#port-channel load-balance fm6000 10
switch(config)#

port-channel min-links review interval

The port-channel min-links review interval command enables or disables timer based min-links review feature for all port-channels.

The no port-channel min-links review interval and default port-channel min-links review intervalcommands restore the default min-links-timeout-base to 180 seconds by removing the corresponding port-channel min-links review interval command from running-config.

Command Mode

Global Configuration

Command Syntax

port-channel min-links review interval timeout(seconds)

no port-channel min-links review interval

default port-channel min-links review interval

Guidelines

The min-links-timeout-base interval for port-channels can be set within the range of 0 to 600 seconds. When setting the review interval to zero, the command will have the following effect:
  • Disables the timer-based min-links review feature for all port-channels.
    • For LACP port-channels, it prevents the port-channel from bringing link up (even after one or more member ports were negotiated to collect or distribute (rx or tx)) until there are sufficient member interfaces ready to join the port-channel. Meanwhile, the partner can enable the port-channel link with fewer than required member interfaces. This configuration does not impact port-channels without min-links configuration.

Related Commands

Example:
This command sets the port-channel min-links interval to 200 seconds.
switch(config)#port-channel min-links review interval 200

port-channel min-links

The port-channel min-links command specifies the minimum number of interfaces that the configuration mode LAG requires to become active. If there are fewer ports than specified by this command, the port channel interface does not become active. The default min-links value is 0.

The no port-channel min-links and default port-channel min-links commands restore the default min-links setting for the configuration mode LAG by removing the corresponding port-channel min-links command from the configuration.

Note: In static LAGs, the min-links value must be met for the LAG to be active. The LAG will not become active until it has at least the min-links number of functioning links in the channel group. If failed links cause the number to drop below the minimum, the LAG will go down and administrator action will be required to bring it back up. In dynamic LAGs, the LACP protocol must determine that at least min-links physical ports are aggregable (they are physically compatible and have the same keys both remotely and locally) before it begins negotiating to make any ports active members of the port-channel. However once negotiation begins, an error on the partner’s side or an error in programming of member interfaces can cause the LAG to become active with fewer than the minimum number of links. EOS evaluates min-links after min-links-review-timeout (linearly proportional to configured min-links) when LACP protocol collecting and/or distributing state changes. If the number of active member interfaces in a port-channel is less than configured min-links, it brings the corresponding port-channel Link Down and syslogs LAG-4-MINLINK_INTF_INSUFFICIENT message. If additional interfaces get programmed as collecting and distributing, EOS re-evaluates min-links on the port-channel. If sufficient number of interfaces are available to be a part of port-channel, then all interfaces of the corresponding port-channel are re-enabled for LACP negotiation and the port-channel becomes Link Up. LAG-4-MINLINK_INTF_NORMAL is syslogged after min-links-review-timeout if the min-links condition is satisfied; otherwise LAG-4-MINLINK_INTF_INSUFFICIENT is syslogged and the port-channel goes Link Down. If an interface remains in collecting state but not in distributing state for min-links-review-timeout, it is moved out of collecting state. It is periodically re-enabled after min-links-retry-timeout (which is 200 seconds) till it progresses to collecting and distributing. Meanwhile, if a port-channel becomes Link Up because sufficient number of interfaces progressed to collecting and distributing states, then this interface is enabled for LACP negotiation.

Command Mode

Interface-Port-Channel Configuration

Command Syntax

port-channel min-links quantity

no port-channel min-links

default port-channel min-links

Parameters
  • quantity Minimum number of interfaces. Value range varies by platform. Default value is 0.
Example:
These commands set 4 as the minimum number of ports required for port channel 13 to become active.
switch(config)#interface port-channel 13
switch(config-if-Po13)#port-channel min-links 4
switch(config-if-Po13)#show active
interface Port-Channel13
 port-channel min-links 4
switch(config-if-Po13)#

show lacp aggregates

The show lacp aggregates command displays aggregate IDs and the list of bundled ports for all specified port channels.

Command Mode

EXEC

Command Syntax

show lacp [PORT_LIST] aggregates [PORT_LEVEL] [INFO_LEVEL]

Note: PORT_LEVEL and INFO_LEVEL parameters can be placed in any order.
Parameters
  • PORT_LIST Port channels for which aggregate information is displayed. Options include:
    • <no parameter> All configured port channels.
    • c_range Channel list (number, range, or comma-delimited list of numbers and ranges).
  • PORT_LEVEL Ports displayed, in terms of aggregation status. Options include:
    • <no parameter> Ports bundled by LACP into the port channel.
    • all-ports All channel group ports, including channel group members not bundled into the port channel interface.
  • INFO_LEVEL Amount of information that is displayed. Options include:
    • <no parameter> Aggregate ID and bundled ports for each channel.
    • brief Aggregate ID and bundled ports for each channel.
    • detailed Aggregate ID and bundled ports for each channel.
Example:
This command lists aggregate information for all configured port channels.
switch>show lacp aggregates

Port Channel Port-Channel1:
 Aggregate ID: 
[(8000,00-1c-73-04-36-d7,0001,0000,0000),(8000,00-1c-73-09-a0-f3,0001,0000,0000)]
Bundled Ports: Ethernet43 Ethernet44 Ethernet45 Ethernet46
Port Channel Port-Channel2:
 Aggregate ID: 
[(8000,00-1c-73-01-02-1e,0002,0000,0000),(8000,00-1c-73-04-36-d7,0002,0000,0000)]
Bundled Ports: Ethernet47 Ethernet48
Port Channel Port-Channel3:
 Aggregate ID: 
[(8000,00-1c-73-04-36-d7,0003,0000,0000),(8000,00-1c-73-0c-02-7d,0001,0000,0000)]
Bundled Ports: Ethernet3 Ethernet4
Port Channel Port-Channel4:
 Aggregate ID: 
[(0001,00-22-b0-57-23-be,0031,0000,0000),(8000,00-1c-73-04-36-d7,0004,0000,0000)]
Bundled Ports: Ethernet1 Ethernet2
Port Channel Port-Channel5:
 Aggregate ID: 
[(0001,00-22-b0-5a-0c-51,0033,0000,0000),(8000,00-1c-73-04-36-d7,0005,0000,0000)]
Bundled Ports: Ethernet41
switch>

show lacp counters

The show lacp counters command displays LACP traffic statistics.

Command Mode

EXEC

Command Syntax

show lacp [PORT_LIST] counters [PORT_LEVEL] [INFO_LEVEL]

Note: PORT_LEVEL and INFO_LEVEL parameters can be placed in any order.
Parameters
  • PORT_LIST Ports for which port information is displayed. Options include:
    • <no parameter> All configured port channels.
    • c_rangePorts in specified channel list (number, number range, or list of numbers and ranges).
    • interface Ports on all interfaces.
    • interface ethernet e_num Port on Ethernet interface specified by e_num.
    • interface port-channel p_num Port on port channel interface specified by p_num.
  • PORT_LEVELPorts displayed, in terms of aggregation status. Options include:
    • <no parameter> Only ports bundled by LACP into an aggregate.
    • all-ports All ports, including LACP candidates that are not bundled.
  • INFO_LEVEL Amount of information that is displayed. Options include:
    • <no parameter> Displays packet transmission (TX and RX) statistics.
    • brief Displays packet transmission (TX and RX) statistics.
    • detailed Displays packet transmission (TX and RX) statistics and actor-partner statistics.
Example:
This command displays transmission statistics for all configured port channels.
switch>show lacp counters brief

LACPDUs Markers Marker Response
Port StatusRX TX RXTX RXTX Illegal
------------------------------------------------------------------
Port Channel Port-Channel1:
Et43 Bundled 396979 3969590 00 00
Et44 Bundled 396979 3969590 00 00
Et45 Bundled 396979 3969590 00 00
Et46 Bundled 396979 3969590 00 00

Port Channel Port-Channel2:
Et47 Bundled 396836 3968830 00 00
Et48 Bundled 396838 3968830 00 00

switch>

show lacp interface

The show lacp interface command displays port status for all port channels that include the specified interfaces. Within the displays for each listed port channel, the output displays sys-id, partner port, state, actor port, and port priority for each interface in the channel.

Command Mode

EXEC

Command Syntax

show lacp interface [INTERFACE_PORT] [PORT_LEVEL] [INFO_LEVEL]

Note: INTERFACE_PORT is listed first when present. Other parameters can be listed in any order.
Parameters
  • INTERFACE_PORT Interfaces for which information is displayed. Options include:
    • <no parameter> All interfaces in channel groups.
    • ethernet e_num Ethernet interface specified by e_num.
    • port-channel p_num Port channel interface specified by p_num.
  • PORT_LEVEL Ports displayed, in terms of aggregation status. Options include:
    • <no parameter> Command lists data for ports bundled by LACP into the aggregate.
    • all-ports Command lists data for all ports, including LACP candidates that are not bundled.
  • INFO_LEVEL Amount of information that is displayed. Options include:
    • <no parameter> Displays same information as brief option.
    • brief Displays LACP configuration data, including sys-id, actor, priorities, and keys.
    • detailed Includes brief option information plus state machine data.
Example:
This command displays LACP configuration information for all ethernet interfaces.
switch>show lacp interface
State: A = Active, P = Passive; S=ShortTimeout, L=LongTimeout;
 G = Aggregable, I = Individual; s+=InSync, s-=OutOfSync;
 C = Collecting, X = state machine expired,
 D = Distributing, d = default neighbor state

 | Partner Actor
Port Status| Sys-id Port# State OperKey PortPriPort#
----------------------------------------------------------------------------
Port Channel Port-Channel1:
Et43 Bundled | 8000,00-1c-73-09-a0-f343 ALGs+CD0x0001 32768 43
Et44 Bundled | 8000,00-1c-73-09-a0-f344 ALGs+CD0x0001 32768 44
Et45 Bundled | 8000,00-1c-73-09-a0-f345 ALGs+CD0x0001 32768 45
Et46 Bundled | 8000,00-1c-73-09-a0-f346 ALGs+CD0x0001 32768 46
Port Channel Port-Channel2:
Et47 Bundled | 8000,00-1c-73-01-02-1e23 ALGs+CD0x0002 32768 47
Et48 Bundled | 8000,00-1c-73-01-02-1e24 ALGs+CD0x0002 32768 48

 | Actor
Port Status| State OperKeyPortPriority
-------------------------------------------------------
Port Channel Port-Channel1:
Et43 Bundled | ALGs+CD0x0001 32768
Et44 Bundled | ALGs+CD0x0001 32768
Et45 Bundled | ALGs+CD0x0001 32768
Et46 Bundled | ALGs+CD0x0001 32768
Port Channel Port-Channel2:
Et47 Bundled | ALGs+CD0x0002 32768
Et48 Bundled | ALGs+CD0x0002 32768

switch>

show lacp internal

The show lacp internal command displays the local LACP state for all specified channels. Local state data includes the state machines and LACP protocol information.

Command Mode

EXEC

Command Syntax

show lacp [PORT_LIST] internal [PORT_LEVEL] [INFO_LEVEL]

Parameters
  • PORT_LIST Interface for which port information is displayed. Options include:
    • <no parameter> All configured port channels.
    • c_rangePorts in specified channel list (number, number range, or list of numbers and ranges).
    • interface Ports on all interfaces.
    • interface ethernet e_num Ethernet interface specified by e_num.
    • interface port-channel p_num Port channel interface specified by p_num.
  • PORT_LEVEL Ports displayed, in terms of aggregation status. Options include:
    • <no parameter> Command lists data for ports bundled by LACP into an aggregate.
    • all-ports Command lists data for all ports, including LACP candidates that are not bundled.
  • INFO_LEVELAmount of information that is displayed. Options include:
    • <no parameter> Displays same information as brief option.
    • brief Displays LACP configuration data, including sys-id, actor, priorities, and keys.
    • detailed Includes brief option information plus state machine data.
    Note: PORT_LEVEL and INFO_LEVEL parameters can be placed in any order.
Example:
This command displays internal data for all configured port channels.
switch>show lacp internal

LACP System-identifier: 8000,00-1c-73-04-36-d7
State: A = Active, P = Passive; S=ShortTimeout, L=LongTimeout;
 G = Aggregable, I = Individual; s+=InSync, s-=OutOfSync;
 C = Collecting, X = state machine expired,
 D = Distributing, d = default neighbor state
 |Partner Actor
Port Status| Sys-id Port#StateOperKeyPortPriority
----------------------------------------------------------------------------
Port Channel Port-Channel1:
Et43 Bundled | 8000,00-1c-73-09-a0-f343ALGs+CD 0x0001 32768
Et44 Bundled | 8000,00-1c-73-09-a0-f344ALGs+CD 0x0001 32768
Et45 Bundled | 8000,00-1c-73-09-a0-f345ALGs+CD 0x0001 32768
Et46 Bundled | 8000,00-1c-73-09-a0-f346ALGs+CD 0x0001 32768

show lacp peer

The show lacp peer command displays the LACP protocol state of the remote neighbor for all specified port channels.

Command Mode

EXEC

Command Syntax

show lacp [PORT_LIST] peer [PORT_LEVEL] [INFO_LEVEL]

Note: PORT_LEVEL and INFO_LEVEL parameters can be placed in any order.
Parameters
  • PORT_LISTInterface for which port information is displayed. Options include:
    • <no parameter> Displays information for all configured port channels.
    • c_range Ports in specified channel list (number, number range, or list of numbers and ranges).
    • interface Ports on all interfaces.
    • interface ethernet e_num Ethernet interface specified by e_num.
    • interface port-channel p_num Port channel interface specified by p_num.
  • PORT_LEVEL Ports displayed, in terms of aggregation status. Options include:
    • <no parameter> Command lists data for ports bundled by LACP into an aggregate.
    • all-ports Command lists data for all ports, including LACP candidates that are not bundled.
  • INFO_LEVEL Amount of information that is displayed. Options include:
    • <no parameter> Displays same information as brief option.
    • brief Displays LACP configuration data, including sys-id, actor, priorities, and keys.
    • detailed Includes brief option information plus state machine data.
Example:
This command displays the LACP protocol state of the remote neighbor for all port channels.
switch>show lacp peer

State: A = Active, P = Passive; S=ShortTimeout, L=LongTimeout;
 G = Aggregable, I = Individual; s+=InSync, s-=OutOfSync;
 C = Collecting, X = state machine expired,
 D = Distributing, d = default neighbor state
 |Partner
Port Status| Sys-idPort# State OperKeyPortPri
----------------------------------------------------------------------------
Port Channel Port-Channel1:
Et1Bundled | 8000,00-1c-73-00-13-191 ALGs+CD0x000132768
Et2Bundled | 8000,00-1c-73-00-13-192 ALGs+CD0x000132768
Port Channel Port-Channel2:
Et23 Bundled | 8000,00-1c-73-04-36-d7 47 ALGs+CD0x000232768
Et24 Bundled | 8000,00-1c-73-04-36-d7 48 ALGs+CD0x000232768
Port Channel Port-Channel4*:
Et3Bundled | 8000,00-1c-73-0b-a8-0e 45 ALGs+CD0x000132768
Et4Bundled | 8000,00-1c-73-0b-a8-0e 46 ALGs+CD0x000132768
Port Channel Port-Channel5*:
Et19 Bundled | 8000,00-1c-73-0c-30-09 49 ALGs+CD0x000532768
Et20 Bundled | 8000,00-1c-73-0c-30-09 50 ALGs+CD0x000532768
Port Channel Port-Channel6*:
Et6Bundled | 8000,00-1c-73-01-07-b9 49 ALGs+CD0x000132768
Port Channel Port-Channel7*:
Et5Bundled | 8000,00-1c-73-0f-6b-22 51 ALGs+CD0x000132768
Port Channel Port-Channel8*:
Et10 Bundled | 8000,00-1c-73-10-40-fa 51 ALGs+CD0x000132768

* - Only local interfaces for MLAGs are displayed. Connect to the peer to
see the state for peer interfaces.
switch>

show lacp sys-id

The show lacp sys-id command displays the System Identifier the switch uses when negotiating remote LACP implementations.

Command Mode

EXEC

Command Syntax

show lacp sys-id [INFO_LEVEL]

Parameters
  • INFO_LEVEL Amount of information that is displayed. Options include:
    • <no parameter> Displays system identifier.
    • brief Displays system identifier.
    • detailed Displays system identifier and system priority, including the MAC address.
Examples:
  • This command displays the system identifier.
    switch>show lacp sys-id brief
    8000,00-1c-73-04-36-d7
  • This command displays the system identifier and system priority.
    switch>show lacp sys-id detailed
    System Identifier used by LACP:
    System priority: 32768Switch MAC Address: 00:1c:73:04:36:d7
    802.11.43 representation: 8000,00-1c-73-04-36-d7

show load-balance profile

The show load-balance profile command displays the contents of the specified load balance profiles. Load balance profiles specify parameters used by hashing algorithms that distribute traffic across ports comprising a port channel or among component ECMP routes.

Command Mode

EXEC

Command Syntax

show load-balance profile [PROFILES]

Parameters
  • PROFILES Load balance profiles for which command displays contents. Options include:
    • <no parameter> Displays all load balance profiles.
    • profile_name Displays specified profile.
Related Commands
Example:
This command displays the contents of the LB-1 load balance profile.
switch>show load-balance profile LB-1

---------- LB-1 ----------

Source MAC address hashing ON
Destination MAC address hashingON
Ethernet type hashingON
VLAN ID hashingON
IP protocol field hashingON
DSCP field hashing isON
Symmetric hashing for non-IP packets OFF
Symmetric hashing for IP packets OFF
Random distribution for port-channel ON
Random distribution for ecmp ON

Profile LB-1 is applied on the following
Port-Channel100

---------- myGlobalProfile (global) ----------
L3 hashing is ON
Symmetric hashing is OFF
Hashing mode is flow-based
Hash polynomial is 3
Hash seed is 0
Profile myGlobalProfile (global) is applied on the following
Linecard3
Linecard4
Linecard5
Linecard6

switch>

show port-channel dense

The show port-channel dense command displays the port-channels on the switch and lists their component interfaces, LACP status, and set flags.

Command Mode

EXEC

Command Syntax

show port-channel dense

Example:
This command displays show port-channel dense output:
switch>show port-channel dense

Flags
---------------------------------------------------------------------
a - LACP Active        p - LACP Passive
U - In Use             D - Down
+ - In-Sync            - - Out-of-Sync      i - incompatible with agg
P - bundled in Po      s - suspended        G - Aggregable
I - Individual         S - ShortTimeout     w - wait for agg

Number of channels in use: 2
Number of aggregators:2

 Port-Channel ProtocolPorts
-------------------------------------------------------
 Po1(U) LACP(a)Et47(PG+) Et48(PG+)
 Po2(U) LACP(a)Et39(PG+) Et40(PG+)

show port-channel limits

The show port-channel limits command displays groups of ports that are compatible and may be joined into port channels. Each group of compatible ports is called a LAG group. For each LAG group, the command also displays Max interfaces and Max ports per interface.
  • Max interfaces defines the maximum number of active port channels that may be formed out of these ports.
  • Max ports per interface defines the maximum number of active ports allowed in a port channel from the compatibility group.

All active ports in a port channel must be compatible. Compatibility comprises many factors and is specific to a given platform. For example, compatibility may require identical operating parameters such as speed and/or maximum transmission unit (MTU). Compatibility may only be possible between specific ports because of internal organization of the switch.

Command Mode

EXEC

Command Syntax

show port-channel limits

Example:
This command displays show port-channel list output:
switch>show port-channel limits

LAG Group: focalpoint
--------------------------------------------------------------------------
Max port-channels per group: 24, Max ports per port-channel: 16
24 compatible ports: Ethernet1Ethernet2Ethernet3Ethernet4
 Ethernet5Ethernet6Ethernet7Ethernet8
 Ethernet9Ethernet10 Ethernet11 Ethernet12
 Ethernet13 Ethernet14 Ethernet15 Ethernet16
 Ethernet17 Ethernet18 Ethernet19 Ethernet20
 Ethernet21 Ethernet22 Ethernet23 Ethernet24
--------------------------------------------------------------------------

show port-channel load-balance fields

The show port-channel load-balance fields command displays the fields that the hashing algorithm uses to distribute traffic across the interfaces that comprise the port channels.

Command Mode

EXEC

Command Syntax

show port-channel load-balance HARDWARE fields

Parameters
  • HARDWARE ASIC switching device. Selection options depend on the switch model and include:
    • arad
    • fm6000
    • petraA
    • trident
Example:
This command displays the hashing fields used for balancing port channel traffic.
switch>show port-channel load-balance fm6000 fields

Source MAC address hashing for non-IP packets is ON
Destination MAC address hashing for non-IP packets is ON
Ethernet type hashing for non-IP packets is ON
VLAN ID hashing for non-IP packets is ON
VLAN priority hashing for non-IP packets is ON
Source MAC address hashing for IP packets is ON
Destination MAC address hashing for IP packets is ON
Ethernet type hashing for IP packets is ON
VLAN ID hashing for IP packets is ON
VLAN priority hashing for IP packets is ON
IP source address hashing is ON
IP destination address hashing is ON
IP protocol field hashing is ON
TCP/UDP source port hashing is ON
TCP/UDP destination port hashing is ON

switch>

show port-channel load-balance

The show port-channel load-balance command displays the traffic distribution between the member ports of the specified port channels. The command displays distribution for unicast, multicast, and broadcast streams.

The distribution values displayed are based on the total interface counters which start from zero at boot time or when the counters are cleared. For more current traffic distribution values, clear the interface counters of the member interfaces using the clear counters command.

Command Mode

EXEC

Command Syntax

show port-channel load-balance [MEMBERS]

Parameters

  • MEMBERS list of port channels for which information is displayed. Options include:
    • <no parameter> all configured port channels.
    • c_range ports in specified channel list (number, number range, or list of numbers and ranges).

Examples

  • This command displays traffic distribution for all configured port channels.
    switch>show port-channel load-balance
    ChanIdPort Rx-Ucst Tx-Ucst Rx-Mcst Tx-Mcst Rx-Bcst Tx-Bcst
    ------ --------- ------- ------- ------- ------- ------- -------
     8Et10 100.00% 100.00% 100.00% 100.00% 0.00% 100.00%
    ------ --------- ------- ------- ------- ------- ------- -------
     1 Et113.97%42.37%47.71%30.94% 0.43%99.84%
     1 Et286.03%57.63%52.29%69.06%99.57% 0.16%
    ------ --------- ------- ------- ------- ------- ------- -------
     2Et2348.27%50.71%26.79%73.22% 0.00% 100.00%
     2Et2451.73%49.29%73.21%26.78% 0.00% 0.00%
    ------ --------- ------- ------- ------- ------- ------- -------
     4 Et355.97%63.29%51.32%73.49% 0.00% 0.00%
     4 Et444.03%36.71%48.68%26.51% 0.00% 0.00%
    ------ --------- ------- ------- ------- ------- ------- -------
     5Et1939.64%37.71%50.00%90.71% 0.00% 0.00%
     5Et2060.36%62.29%50.00% 9.29% 0.00% 100.00%
    ------ --------- ------- ------- ------- ------- ------- -------
     6 Et6 100.00% 100.00% 100.00% 100.00% 0.00% 100.00%
    ------ --------- ------- ------- ------- ------- ------- -------
     7 Et5 100.00% 0.00% 100.00% 100.00% 0.00% 0.00%
    switch>

show port-channel

The show port-channel command displays information about members the specified port channels.

Command Mode

EXEC

Command Syntax

show port-channel [MEMBERS] [PORT_LIST] [INFO_LEVEL]

Parameters
  • MEMBERS List of port channels for which information is displayed. Options include:
    • <no parameter> All configured port channels.
    • p_range Ports in specified channel list (number, number range, or list of numbers and ranges).
  • PORT_LEVEL Ports displayed, in terms of aggregation status. Options include:
    • <no parameter> Displays information on ports that are active members of the LAG.
    • active-ports Displays information on ports that are active members of the LAG.
    • all-ports Displays information on all ports (active or inactive) configured for LAG.
  • INFO_LEVEL Amount of information that is displayed. Options include:
    • <no parameter> Displays information at the brief level.
    • brief Displays information at the brief level.
    • detailed Displays information at the detail level.
Display Values
  • Port Channel Type and name of the port channel.
  • Time became active Time when the port channel came up.
  • Protocol Protocol operating on the port channel.
  • Mode Status of the Ethernet interface on the port. The status value is Active or Inactive.
  • No active ports Number of active ports on the port channel.
  • Configured but inactive ports Ports configured but that are not actively up.
  • Reason unconfigured Reason why the port is not part of the LAG.

Guidelines

You can configure a port channel to contain many ports, but only a subset may be active at a time. All active ports in a port channel must be compatible. Compatibility includes many factors and is platform specific. For example, compatibility may require identical operating parameters such as speed and maximum transmission unit (MTU). Compatibility may only be possible between specific ports because of the internal organization of the switch.

Examples:
  • This command displays output from the show port-channel command.
    switch>show port-channel 3
    Port Channel Port-Channel3: 
    Active Ports: 
     PortTime became active ProtocolMode
    ----------------------------------------------------------------------- 
     Ethernet3 15:33:41 LACPActive 
     PeerEthernet3 15:33:41 LACPActive 
    
  • This command displays output from the show port-channel active-ports command.
    switch>show port-channel active-ports
    Port Channel Port-Channel3:
    No Active Ports
    Port Channel Port-Channel11:
    No Active Ports
    switch>
  • This command displays output from the show port-channel all-ports command.
    switch>show port-channel all-ports
    Port Channel Port-Channel3:
    No Active Ports
    Configured, but inactive ports:
    PortTime became inactiveReason unconfigured
    ----------------------------------------------------------------------------
    Ethernet3 Alwaysnot compatible with aggregate
    
    Port Channel Port-Channel11:
    No Active Ports
    Configured, but inactive ports:
    PortTime became inactiveReason unconfigured
    ----------------------------------------------------------------------------
    Ethernet25Alwaysnot compatible with aggregate
    Ethernet26Alwaysnot compatible with aggregate