Configuring Layer 1 on the 7130 Platform

Switch interfaces can be used instead of the application interfaces for creating connections between app interfaces and front panel ports. Configure Layer 1 traffic between front panel ports, application FPGA ports, and switch interfaces using the l1 source command.

Adding this connection does not affect previously configured destinations.

This section contains the following topics:

On DCS-7130 series switches, change the default connections dynamically by using the l1 source and configuring the switch interfaces as a source or destination. Connect bidirectional network traffic on a Switch1/26 and an Ethernet 36 interface when using a Layer 2 full profile.

Example
switch(config)# l1 connect Switch1/26 Ethernet36

Configuring Layer 1 on an Interface

Use the following command to connect Layer 1 traffic from the Ethernet interface et2. 
switch(config)# interface ethernet1
switch(config-if-Et1)# l1 source interface et2

Configuring Layer 1 for a MetaMux Interface

MetaMux is an FPGA-based feature available on Arista 7130 platforms. It performs ultra-low latency Ethernet packet multiplexing with or without packet contention queuing. The port to port latency functions as the selected MetaMux profile, using the front panel ingress port, the front panel egress port, the FPGA connector ingress port, and the platform.

Use the l1 source and l1 connect commands to connect the MuxIn and MuxOut ports to Ethernet ports. In this example, the commands connect the first two Mux1 inputs, MuxIn2/1/1 and MuxIn2/1/2 of the MetaMux instance 2 to the ingress ports of Ethernet 17 and 20 and the Mux1 output, MuxOut2/1 of the same instance to the egress port of Ethernet 22.

Example

Use the following commands to configure a Layer 1 topology for a MetaMux interface: 
switch(config)# interface MuxIn 2/1/1
switch(config-if-MuI2/1/1)# l1 source interface Eth5
switch(config-if-MuI2/1/1)# interface MuxIn 2/1/2
switch(config-if-MuI2/1/2)# l1 source interface Eth6
switch(config-if-MuI2/1/2)# interface eth11
switch(config-if-Et22)# l1 source interface muxout 2/1
To verify the configuration, use the show l1 path or show l1 matrix commands: 
switch# show l1 path int et17,20,22
Source                  Destination              Type
----------------------- ------------------------ -------
Ethernet17              MuxIn2/1/1 (Ap2/1)       dynamic
Ethernet20              MuxIn2/1/2 (Ap2/2)       dynamic
MuxOut2/1 (Ap2/4)       Ethernet22               dynamic

switch# show l1 matrix int et5,6,11
                Ethernet   MuxIn
                5 6 11     2/1/1* 2/1/2*
        Et5 -> -|-|-|------+      |
        Et6 -> -|-|-|-------------+
        MuO2/1* -> -|-|-+
        MAC -> -+-+
   * indicates interface is a function interface

For more information about MetaMux interfaces, see Software Downloads for the 7130 platform.

Configuring Layer 1 for MultiAccess

7130 platforms provide support for MultiAccess, an FPGA-based feature. It performs low-latency Ethernet multiplexing with optional packet contention queuing, storm control, VLAN tunneling, and packet access control. The interface to interface latency provides functionality for the selected MultiAccess profile, front panel interfaces, MultiAccess interfaces, configuration settings, and platform used. The MultiAccess feature uses the Downstream and Upstream interfaces to connect to Ethernet interfaces.

Example

To configure Multiaccess Layer 1 topology, use the following commands. In this case, you have an active Multiaccess instance with an ID of 2 to bidirectionally connect the two Downstream interfaces from Group 2 to Ethernet interfaces, 17 and 20.
switch(config)# interface Ethernet17
switch(config-if-Et17)# l1 source interface Downstream2/1/1
switch(config-if-Et17)# interface Downstream2/1/1
switch1(config-if-Dn2/1/1)# l1 source interface Ethernet17
switch(config-if-Dn2/1/1)#
                
switch(config)# interface Ethernet20
switch(config-if-Et20)# l1 source interface Downstream2/1/2
switch(config-if-Et20)# interface Downstream2/1/2
switch(config-if-Dn2/1/2)# l1 source interface Ethernet20
switch(config-if-Dn2/1/2)#
Next, add the Upstream interface, Upstream2/1, to the configuration:
oml201(config)# interface Ethernet25
switch(config-if-Et25)# l1 source interface Upstream2/1
switch(config-if-Et25)# interface Upstream2/1
switch(config-if-Up2/1)# l1 source interface Ethernet25
switch(config-if-Up2/1)#
To display the configuration, use the show l1 path and the show l1 matrix command: 
switch# show l1 path interface Ethernet17,20,25
Source                        Destination                   Type   
----------------------------- ----------------------------- -------
Ethernet17                    Downstream2/1/1 (Ap1/5)       dynamic
Ethernet20                    Downstream2/1/2 (Ap1/6)       dynamic
Ethernet25                    Upstream2/1 (Ap1/12)          dynamic
Downstream2/1/1 (Ap1/5)       Ethernet17                    dynamic
Downstream2/1/2 (Ap1/6)       Ethernet20                    dynamic
Upstream2/1 (Ap1/12)          Ethernet25                    dynamic

switch# show l1 matrix interface Ethernet17,20,25
            Ethernet   Downstream      Upstream
            17 20 25   2/1/1* 2/1/2*   2/1* 
   Et17 -> -|--|--|----+      |        |    
   Et20 -> -|--|--|-----------+        |    
   Et25 -> -|--|--|--------------------+    
Dn2/1/1* -> -+  |  |                         
Dn2/1/2* -> ----+  |
Up2/1* -> ---------+                           
* indicates interface is a function interface

For more information about MultiAccess interfaces, see Software Downloads for the 7130 platform.

Addressing 7130 Platform Speed Mismatch

When configuring the L1 source of an interface, the following speed restrictions should be considered:
  • The configuration for an L1 source only applies if the source and destination interfaces have the same speed configuration.
  • If you configure an interface and a single lane with a multi-lane speed, such as 40Gbps, all other lanes must also be sourced individually. In the config mode, display the additional lanes with the service interface inactive expose command.
If you configure the two interfaces with mismatched speeds, the mapping does not apply to the configuration. When running the l1 source command, the console does not display any warnings that a speed mismatch exists. When you execute the l1 source command, you can see if the configuration accepts the parameters. 
(config)# int sw1/1/1
(config-if-sw1/1/1)# speed 10g
(config-if-sw1/1/1)# int et1/1
(config-if-et1/1)# speed 1g
(config-if-et1/1)# l1 source int sw1/1/1

Interface          Source Interface       Type
------------------ ---------------------- -------
Ethernet1/1                               dynamic
Check the show logging output for warnings about speed mismatch. In this example, you see the following syslog text: 
L1SOURCE-6-SPEED_MISMATCH: Speed mismatch found between Layer1 source Switch1/1/1 and destination Ethernet1/1, configuration has not been applied.
If you attempt to configure an unsupported interface, such as a static interface, as a source, the show logging output displays the following log message:
L1SOURCE-6-UNSUPPORTED: The configured Layer1 source for interface name is unsupported.
When you resolve the misconfiguration, the show logging output displays the following log message:
L1SOURCE-6-OK: Layer1 sourcing has been successfully applied between source source interface and destination destination interface>.

Configuring the 7130 Platform and Multilane Sourcing

Source the lanes individually if an interface configuration has a multi-lane speed, such as 40Gbps. Display the individual lanes using the service interface inactive expose command while in the configure mode. Configure the individual lanes with a corresponding interface name. To learn more about configuring port speeds, see speed.

See the example for an Ethernet interface connecting to a switch interface at 40Gbps.

Example

The following commands expose the individual lanes on interface sw1 and set the sources and speed.
(config)# service interface inactive expose
(config)# int sw1/1/1
(config-if-sw1/1/1)# speed 40g
(config-if-sw1/1/1)# int et1/1
(config-if-et1/1)# speed 40g
(config-if-et1/1)# l1 source int sw1/1/1
(config-if-et1/1)# int et1/2
(config-if-et1/2)# l1 source int sw1/1/2
(config-if-et1/2)# int et1/3
(config-if-et1/3)# l1 source int sw1/1/3
(config-if-et1/3)# int et1/4
(config-if-et1/4)# l1 source int sw1/1/4
(config-if-et1/4)# show l1 source int et1/1-4

Interface          Source Interface       Type
------------------ ---------------------- -------
Ethernet1/1        Switch1/1/1            dynamic
Ethernet1/2        Switch1/1/2            dynamic
Ethernet1/3        Switch1/1/3            dynamic
Ethernet1/4        Switch1/1/4            dynamic

Using Show Commands to Confirm Source Configurations

If the interfaces have matching speeds and the configuration applies to the interface, confirm the configuration by running the show l1 source command on the destination interface.
(config-if-et1/1)# l1 source int sw1/1/1
(config-if-et1/1)# show l1 source int et1/1
Interface          Source Interface       Type
------------------ ---------------------- -------
Ethernet1/1        Switch1/1/1            dynamic
If a speed mismatch occurs, the show l1 source output does not display mapping for the mismatched interface. To display the speed of the source before the mismatch occurs, use the show active command and check the output. View the mismatched speeds by running the show interface status command for each interface. 
(config-if-et1/1)# l1 source int sw1/1/1
(config-if-et1/1)# show l1 source int et1/1
                
Interface           Source Interface       Type
------------------ ---------------------- -------
Ethernet1/1   	                      dynamic
                
(config-if-et1/1)# show active
interface Ethernet1
l1 source interface Switch1/1/1
(config-if-et1/1)# show interface et1/1 status
Port  Name   Status    Vlan        Duplex       Speed Type        Flags Encapsulation
----- ------ --------- ----------- ------------ ----- ----------- --------------------
Et1          signal    Not Bridged full         10G   10GBASE-CR

(config-if-et1/1)# show interface sw1/1/1 status

Port     Name    Status        Vlan   Duplex       Speed  Type   Flags Encapsulation
-------- ------- ------------- ------ ------------ ------ ------ --------------------
Sw1/1/1          notconnect    1      full         1G     N/A

Static Mappings and Speed Mismatches

Some configurations may appear even if a speed mismatch occurs on the interfaces. You may see the configurations when reviewing the static interface mappings. You cannot change the static mappings using the CLI and the l1 source command or change the speed. Compare this to dynamic mappings, which can be configured and updated based on speed changes.

The example output displays the static mappings between the switch and application interfaces on a DCS-7130LBR series device:
#show l1 source interface sw1/25/1-8
                
Interface          Source Interface       Type
------------------ ---------------------- ------
Switch1/25/1       Application1/25        static
Switch1/25/2       Application1/26        static
Switch1/25/3       Application1/27        static
Switch1/25/4       Application1/28        static
Switch1/25/5       Application1/57        static
Switch1/25/6       Application1/58        static
Switch1/25/7       Application1/59        static
Switch1/25/8       Application1/60        static

L1 Configuration Considerations

The following information should be considered when using the L1 source suite of commands:

  • EOS only enforces speed mismatch on Ethernet to Ethernet, switch to switch, and Ethernet to switch connections. Be sure both sides of a connection have matching speeds to avoid linking between 10G and 40G interfaces. Currently, EOS does not enforce speed checks on the following interface:
    • Cpu
  • The show l1 source command does not display a mapping for a mismatched interface. Run the show active command to display the source before speeds mismatched. The default source is configured if the output does not display a mapping.

For more information, refer to https://www.arista.com/en/support/toi/eos-4-27-1f/14877-switchapp-ultra-low-latency-packet-switch.