Tag :: EOS 4.26.0F

The L2 EVPN MPLS feature is available when configuring BGP in the multi-agent routing protocol model. Ethernet VPN (EVPN) is an extension of the BGP protocol introducing a new address family: L2VPN (address family number 25) / EVPN (subsequent address family number 70). It is used to exchange overlay MAC and IP address reachability information between BGP peers.

This feature detects duplicate IP addresses configured on the switch already owned by hosts the switch has already learned. When the duplicate IP address is detected, a syslog message will be generated. It can help the network operator to identify IP address misconfiguration.

Disabling the flooding of broadcast, multicast, and unknown unicast traffic into the VXLAN fabric can significantly reduce bandwidth consumption in the VXLAN underlay. This is particularly beneficial in use cases where such traffic is unnecessary. This feature, exclusively supported with EVPN, allows for the selective flooding of ARP and/or ND traffic, offering further control over bandwidth usage.

EOS-4.24.0 adds support for hardware-accelerated sFlow on R3 systems. Without hardware acceleration, all sFlow processing is done in software, which means performance is heavily dependent on the capabilities of the host CPU. Aggressive sampling rates also decrease the amount of processing time available for other EOS applications.

IPv4 routes of certain prefix lengths can be optimized for enhanced route scale. This document describes the enhancements done to IPv4 route scale in subsequent EOS releases.

If a network device uses deep packet inspection for load balancing, RFC6790 recommends deployments to use entropy label in LDP to improve load balancing in MPLS networks by providing sufficient entropy in the label stack itself.

If a network device uses deep packet inspection for load balancing, RFC6790 recommends deployments to use entropy label in LDP to improve load balancing in MPLS networks by providing sufficient entropy in the label stack itself.

The TCP MSS clamping feature involves clamping the maximum segment size (MSS) in the TCP header of TCP SYN packets if it exceeds the configured MSS ceiling limit for the interface. Clamping MSS value helps in avoiding IP fragmentation in tunnel scenarios by ensuring that MSS is small enough to accommodate the extra overhead of GRE and tunnel outer IP headers. One of the most common use cases for this feature is connectivity towards Cloud providers via GRE which require asymmetric routing (for example DDoS protection).

This solution allows delivery of multicast traffic in an IP-VRF using multicast in the underlay network. It builds on top of [L2-EVPN], adding support for L3 VPNs and Integrated Routing and Bridging (IRB).  The protocol used to build multicast trees in the underlay network is PIM Sparse Mode.

The postcard telemetry (GreenT - GRE Encapsulated Telemetry) feature is used to gather per flow telemetry information like path and per hop latency. For network monitoring and troubleshooting flow related issues, it is desirable to know the path, latency and congestion information for flows at different times.

The`ptp forward-v1` command configures the switch to forward Precision Time Protocol version 1 packets as regular multicast traffic. By default, when PTP is enabled and PTPv1 packets are received on the PTP enabled interfaces, these packets are trapped by the CPU, logged and discarded. The feature is already supported on various Arista platforms, this article highlights added support on the 7280R/7280R2/7020R/7500R/7500R2 platforms in EOS 4.26.0F and on the 7280R3/7500R3/7800R3/7289 platforms in EOS 4.29.0F. It highlights some differences in support for 7280/7500/7800 R/R2 platforms versus 7280/7500/7800 R3 platforms.

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.