Displaying ECMP Load Balancing Info for VXLAN

As discussed in the earlier sections, equal-cost multi-path (ECMP) load balancing defines a routing strategy in which next-hop packet forwarding to a single destination can occur over multiple paths.

In case of VTEP interconnections, it is possible to verify that multiple next hops are available with the tunnel-show command.

It is also possible to verify that ECMP is applied in hardware (provided multiple next hops exist) and to display the selection of the next hops by checking the RIB table with the vrouter-rib-routes-show command.

For example, the user has configured a tunnel called leaf1toleaf2 with a local IP address 22.3.11.1 and a remote IP address 32.4.11.1. The network design provides two next hops to route the VXLAN traffic from the local VTEP to the remote one: 192.178.0.6 and 192.178.0.2.

The tunnel-show and vrouter-rib-routes-show commands can be used to display the tunnel’s specific next hops as well as the route info for the remote end point (32.4.11.0/24) in the RIB table, as shown below:

CLI (network-admin@leaf1) > tunnel-show name leaf1toleaf2 ecmp-nexthops layout vertical

scope:             local

name:              leaf1toleaf2

type:              vxlan

vrouter-name:      scorpius-vxlan-01

local-ip:          17.60.13.1

remote-ip:         17.60.11.1

router-if:         eth0.3

next-hop:          192.178.0.6

next-hop-mac:      66:0e:94:f7:31:f0

nexthop-vlan:      4091

active:            yes

state:             ok

bfd:               disabled

bfd-state:         not-replicator-vtep

route-info:        17.60.11.0/30

ports:             49

auto-tunnel:       static

scope:             local

name:              leaf1toleaf2

type:              vxlan

vrouter-name:      scorpius-vxlan-01

local-ip:          17.60.13.1

remote-ip:         17.60.11.1

router-if:         eth0.3

next-hop:          192.178.0.2

next-hop-mac:      66:0e:94:b7:95:c3

nexthop-vlan:      4092

active:            yes

state:             ok

bfd:               disabled

bfd-state:         not-replicator-vtep

route-info:        17.60.11.0/30

ports:             272

auto-tunnel:       static

CLI (network-admin@leaf1) > vrouter-rib-routes-show ip 32.4.11.0

vrid         ip            prelen  number-of-nexthops  nexthop            flags          vlan          intf_ip        intf-id

---- -----------  ------- ------------------- --------            ------         -----          --------        --------

0        17.60.11.0        30          2                     192.178.0.6  ECMP,in-hw  4091          192.178.0.5           1

0        17.60.11.0        30          2                     192.178.0.2  ECMP,in-hw  4092  192.178.0.1           0