EOS 4.34.0F TOI

A traffic storm is a flood of packets entering a network, resulting in excessive traffic and degraded performance. Storm control prevents network disruptions by limiting traffic beyond specified thresholds on individual physical LAN interfaces. Storm control monitors inbound traffic levels over one-second intervals and compares the traffic level with a specified benchmark. The storm-control command configures and enables storm control on the configuration mode physical interface.

Dot1q (802.1Q) is a tunneling protocol that encapsulates traffic from multiple customer (c-tag) VLANs in an additional single outer service provider (s-tag) VLAN for transit across a larger network structure that includes traffic from all customers. Tunneling eliminates the service provider requirement that every VLAN be configured from multiple customers, avoiding overlapping address space issues.

The packet path, prerequisites, and restrictions listed in this document apply to this feature as well Dynamic Twice NAT is a variant of the dynamic NAT feature where both the source and destination IP can be modified while forwarding a packet. One of the IP addresses will be dynamically assigned, while the other will be statically assigned.

In the realm of network service level agreements (SLAs), a customer often commits to a certain level of service for their clients. This may necessitate limiting bandwidth at the Layer 3 sub-interface level. Currently, egress service policies can achieve bandwidth control, but ingress control lacks a similar mechanism.

Linear pluggable optics (LPO) represent a significant advancement in transceiver technology. These modules are designed to reduce costs, power consumption, and latency compared to traditional Digital Signal Processing (DSP) based transceivers.

The Linux audit system provides the ability to record security events on the switch. Audit rules must be configured and enabled at the CLI. Audit rules can be configured in different groups to assist with organization and maintenance.

The Lowest Load feature uses load as a key metric for selecting the best path. When this metric is prioritized, routers will choose the path with the lowest load as the best option.

Multicast NAT is a feature that performs NAT translations on multicast traffic. It can be configured under SVIs,

Private VLAN is a feature that segregates a regular VLAN broadcast domain while maintaining all ports in the same IP subnet. There are three types of VLAN within a private VLAN

Leaf Smart System Upgrade (SSU) provides the ability to upgrade the EOS image with minimal traffic disruption. To perform the SSU, Spanning Tree Protocol (STP) should either be configured as MSTP or Rapid-PVST mode or should be disabled. Meanwhile, all ports should be configured with admin edge ports (i.e., all ports are supposed to connect to host only) and the BPDU guard should be enabled for all edge ports.

Access Control Lists (ACL) use packet classification to mark certain packets going through the packet processor pipeline and then take configured action against them. Rules are defined based on various fields of packets and usually TCAM is used to match packets to rules. For example, there can be a rule to match the packet source IP address against a list of IP addresses, and drop the packet if there is a match. This will be expressed in TCAM with multiple entries matching the list of IP addresses. Number of entries is reduced by masking off bits, if possible. TCAM is a limited resource, so with classifiers having a large number of rules and a big field list, TCAM runs out of resources.

This feature is only applicable to shaped port-channel subinterfaces. Traffic destined to a shaped port-channel subinterface would be load-balanced across all members of the port-channel. Shaping configured on the port-channel subinterface will be directly used across all the members of port-channel. Load-balancing criterion for flows destined to a shaped port-channel subinterface is the same as parent port-channel load-balancing criterion. Each shaped port-channel subinterface consumes as many SPPID (System physical port identifier) as the number of members added to the port-channel along with one extra port-channel resource (LAG ID) to combine all these SPPID. Anchor based approach is default behavior and we explicitly need to enable and reload the system for this feature to work.

SwitchApp is an FPGA-based feature available on Arista’s 713x-Series platforms. It performs ultra low latency Ethernet packet switching. Its packet switching feature set, port count, and port to port latency are a function of the selected SwitchApp profile. Detailed latency measurements are available in the userguide on the Arista Support site.

Before release 4.34.0F traffic in Port Mode PW was always classified based on COS-To-TC global map irrespective of trust mode. This feature allows users to classify traffic in accordance with trust mode, default CoS and default DSCP of the interface.

This feature introduces a slot level CLI command for SFP transceivers. When configured, EOS will only manage the transceiver via the low speed hardware pins. The command is intended to be used in situations where SMBUS communication to access transceiver EEPROM is not reliable, which would normally lead to EOS disabling the port. Enabling this feature ignores any EEPROM dependent functionality and only turns on the laser, which may allow the link to come up when the default factory settings for both ends of the link are compatible.

The feature introduces a CLI command for transceiver reinitialization, simulating a physical removal and reinsertion of the transceiver. This is a great feature for remote troubleshooting, when physical access is not possible or convenient. To configure, issue the CLI command "transceiver reinitialize slot" in exec mode. The command takes effect immediately, toggles the reset pin and initiates a transceiver initialization sequence.

When the system exhausts ECMP resources, the Transient ECMP feature enables route programming through a single available next-hop from the original ECMP route. Once the system can program the full ECMP route, the transient ECMP route is removed after successfully installing the ECMP route.

Unidirectional links is a feature that configures an Ethernet interface transmit and receive paths to be independent. Specifically, the transmit path can be up or down independent of the receive path being up or down.

The Unified Forwarding Table (UFT) is a group of memories that is shared between Layer2 and Layer3 lookup tables with capabilities for variable partitions. Rather than separate Layer2 and Layer3 lookup tables of fixed size, the UFT may be partitioned to support user-requested combinations of Layer2 and Layer3 lookup tables of varying sizes. The new UFT partitioning CLI has capabilities to reconfigure individual forwarding table scales (Layer2, Layer3 Unicast, Layer3 Multicast) according to the user’s input. The CLI provides an interface for granular control of the underlying UFT resources.

This feature allows the VRRP MAC to be advertised via EVPN MAC-only routes when VRRP is configured on the VTEP.

This feature allows selecting Differentiated Services Code Point (DSCP) and Traffic Class (TC) values for packets at VTEPs along VXLAN encapsulation and decapsulation directions respectively. DSCP is a field in IP Header and TC is a tag associated with a packet within the switch, both influence the Quality of Service the packet receives. This feature can be enabled via configuration as explained later in this document.

Pathfinder deployments have restrictions on what devices can form a DPS tunnel between them. All the devices are categorized as either Site or Zone transit or Region transit.