TOI Author :: Kallol Mandal

Traceroute and tracert are widely available diagnostic command-line interface commands for displaying possible routes (paths) and transit delays of packets across an Internet Protocol (IP) network. This enhancement applies to IPv4 and IPv6 overlay. The VTEP overlay ICMPs for “time-to-live expired” (aka TTL-expired) are sourced with the VTEP IP which results in the traceroute output to display the VTEP IPs on the overlay packet’s path from source to destination.

Each ARP/ND packet into a switch may generate an update for the switch ARP/Neighbor table and this update may need to be synchronized with the MLAG peer when VXLAN is configured. Prior to this feature, these updates (on a VXLAN setup) are synchronized by sending an UDP packet (one packet per update) containing the IP/MAC/VLAN information from the MLAG peer where the ARP/ND packet is received to the other MLAG peer. 

VXLAN ARP and IPv6 Neighbor Discovery (NDP) packet headend replication capability via VxlanSwFwd matches the COPP rate limit for these packets for the supported platforms regardless of the size of the VXLAN flood VTEP list. However, there still remains a case where the handling capacity is limited by CPU: the handling of ARP broadcast and NS multicast that result from Glean traffic (post routing).

In a VXLAN routing setup using VXLAN Controller Service (VCS), this feature will enable the following on a switch that is running as a VCS client.

Overlay IPv6 routing over VXLAN tunnel using an anycast gateway (direct routing) has been previously supported using the “ipv6 virtual-router” configuration for both the data-plane and EVPN (or CVX) control-plane learning environments. 

Starting with EOS release 4.22.0F, the EVPN VXLAN L3 Gateway using EVPN IRB supports routing traffic from one IPV6

In certain VXLAN deployments with either NSX/Logical Router or EVPN IRB, active nodes hosting a virtual IP address

Selective ARP install is the selective programming of remote ARPs in hardware as received through EVPN Type 2 MAC-IP routes in an EVPN VXLAN/ MPLS Integrated Routing and Bridging (IRB) scenario. Instead of installing every MAC+IP binding received from EVPN into the hardware, the switch installs them only when there is routed traffic destined to the IP, thereby saving TCAM space on the switch. However, there is a tradeoff as there is an initial one-time latency to install the hardware TCAM entry on the first flow of routed traffic to the IP.