• Author : Shamit Kapadia Kapadia


IGP cost for VTEP reachability

Introduction In EVPN deployment with VXLAN underlay when an EVPN type-5 prefix is imported into an IP VRF, the IGP cost of the underlay VTEP reachability is not considered as part of BGP bestpath selection post import. Therefore, if such a prefix is reachable via more than one VTEPs, the IGP metric step in the BGP best-path selection algorithm will not filter out any paths irrespective of the underlay’s IGP metric for the VTEP reachability. If ECMP is enabled in the overlay and multiple paths are found to be otherwise equivalent,  such paths would  form ECMP regardless of the IGP...
Continue reading →

MLAG peer gateway

In an MLAG setup, routing on a switch (MLAG peer) is possible using its own bridge/system MAC, VARP MAC or VRRP MAC. When a peer receives an IP packet with destination MAC set to one of the aforementioned MACs, the packet gets routed if the hardware has enough information to route the packet. The following behavior was observed if the destination MAC is peer’s bridge MAC – the packet is L2 bridged on the peer-link and the routing takes place on the peer. This behavior to use the peer-link to bridge the L3 traffic to the peer is undesirable if heavy routable traffic...
Continue reading →


Get every new post on this blog delivered to your Inbox.

Join other followers: