Tag :: EOS 4.21.0F

The feature allows to create a custom (i.e. named) TC, DP to DSCP mapping profile that can be applied on an interface.

EVPN route advertisements carry RD and RT. RD (Route Distinguisher) : prepend to the tenant’s IP Prefix or MAC address to make it globally unique. RT (Route Target) : a BGP extended community used to tag the EVPN route.  The EVPN import policy is chosen to select what is the target tenant VRF is imported from the global EVPN table.

Normally, a switch traps L2 protocol frames to the CPU. However, certain use-cases may require these frames to be forwarded or dropped. And in cases where the L2 protocol frames are forwarded (eg: Pseudowire), we may require the frames to be trapped to the CPU or dropped. The L2 Protocol Forwarding feature provides a mechanism to control the behavior of L2 protocol frames received on a port or subinterface.

LANZ Mirroring feature allows users to automatically mirror traffic queued as a result of congestion to either CPU or a different interface.

This document describes the latest status of LANZ on DCS 7500R, DCS 7280R and DCS 7020R, for both polling and notifying

IP traceroute and path MTU (PMTU) discovery both require that routers send ICMP reply messages to the host that invokes each network function. When the route to the destination host traverses an MPLS label-switched path (LSP), the label switching routers (LSRs) will also need to send ICMP reply messages to the originating host.

Priority Flow Control is a link-layer flow control mechanism which may be used by an overwhelmed network node to ask its transmitters to stop transmission for a specified period of time. It does so by using special frames known as PFC frames, thus, relieving congestion at the receiver node. With respect to this behavior, PFC is very similar to Link Layer Flow Control ( LLFC ), however, unlike LLFC, PFC allows the overwhelmed node to specify which 802.1Q Class of Service ( CoS ) it wants to stop receiving traffic for. Thus, allowing differentiated treatment of traffic based on CoS.

This feature allows users to view most recent history of offset from master, mean path delay and skew values via CLI command and optionally generate syslogs. To generate syslogs, users must configure threshold values for each metric, and whenever the switch sees an unusual data, it will generate a syslog. Recording and displaying recent history is enabled by default so the data is available in show tech-support command, but syslog feature is disabled by default, and user must configure in order to generate them

Segment Routing Traffic Engineering Policy (SR-TE) aka SR Policy makes use of Segment Routing (SR) to allow a headend to steer traffic along any path without maintaining per flow state in every node. A headend steers traffic into an “SR Policy”. EOS 4.21.0F adds support for SR Policy for the MPLS dataplane (SR-MPLS) for Type-1 SR Policy segments with BGP and locally configured policies as sources of SR Policies on Arista’s 7500, 7280 families of switches.

This feature is available in the VLAN configuration mode. When a switch receives a packet with unknown destination MAC address on a VLAN, L2 miss happens. The current behavior for L2 miss packets is to flood the packet on all ports of the VLAN. In certain cases, there may be a preference to drop or log L2 miss packets instead of flooding them across the VLAN.