Egress ECMP Load Distribution for VXLAN Traffic from the VTEP Switch
Equal-cost multi-path routing (ECMP) defies a routing strategy where next-hop packet forwarding to a single destination can occur over multiple best paths. Tunnel next hops update based on underlay routes information. RIB/FIB information leverages to program next hops for a tunnel remote endpoint. If multiple next hops exist for a tunnel remote endpoint, an ECMP group uses the list of next hops and the tunnel programmed accordingly.
For example, a tunnel leaf1toleaf 2 with a remote IP address 32.4.11.1, Netvisor ONE displays 2 next hops, 192.178.0.6 and 192.178.0.2. Netvisor ONE hashes the traffic going over tunnel leaf1to leaf 2 using these two next hop links.
 
CLI (network-admin@lleaf11) > tunnel-show
scope:                           cluster
name:                            leaf1toleaf2
type:                            vxlan
vrouter-name:                    leafpst1
peer-vrouter-name:               leafpst2
local-ip:                        22.3.11.1
remote-ip:                       32.4.11.1
router-if:                       eth12.11
next-hop:                        192.178.0.6
next-hop-mac:                    66:0e:94:8c:d4:0f
nexthop-vlan:                    4091
remote-switch:                   0
active:                          yes
state:                           ok
error:                           
route-info:                      32.4.11.0/24
scope:                           
name:                            
type:                            
vrouter-name:                    
peer-vrouter-name:               
local-ip:                        
remote-ip:                       
router-if:                       
next-hop:                        192.178.0.2
next-hop-mac:                    66:0e:94:5b:90:2b
nexthop-vlan:                    
remote-switch:                   4092
active:                          0
state:                           ok
error:                           
route-info:                      32.4.11.0/24
scope:                           cluster
name:                            leaf1toleaf2-2nd
type:                            vxlan
vrouter-name:                    leafpst1
peer-vrouter-name:               leafpst2
local-ip:                        22.3.12.1
remote-ip:                       32.4.12.1
router-if:                       eth9.12
next-hop:                        192.178.0.6
next-hop-mac:                    66:0e:94:8c:d4:0f
nexthop-vlan:                    4091
remote-switch:                   0
active:                          yes
state:                           ok
error:                           
route-info:                      32.4.11.0/24
scope:                           
name:                            
type:                            
vrouter-name:                    
peer-vrouter-name:               
local-ip:                        
remote-ip:                       
router-if:                       
next-hop:                        192.178.0.2
next-hop-mac:                    66:0e:94:5b:90:2b
nexthop-vlan:                    
remote-switch:                   4092
active:                          0
state:                           ok
error:                           
route-info:                      32.4.11.0/24
 
CLI (network-admin@leaf-pst-1) > vrouter-rib-routes-show ip 32.4.11.0
vrid ip prelen number-of-nexthops nexthop flags vlan intf_ip intf_id
---- --------- ------ ------------------ ----------- ---------- ---- ----------- -------
0 32.4.11.0 24 2 192.178.0.6 ECMP,in-hw 4091 192.178.0.5 1
0 32.4.11.0 24 2              192.178.0.2 ECMP,in-hw 4092 192.178.0.1 0
 
CLI (network-admin@leaf-pst-1) > vrouter-rib-routes-show ip 32.4.12.0
vrid ip prelen number-of-nexthops nexthop flags vlan intf_ip intf_id
---- --------- ------ ------------------ ----------- ---------- ---- ----------- -------
0 32.4.12.0 24 2 192.178.0.6 ECMP,in-hw 4091 192.178.0.5 1
0 32.4.12.0 24 2 192.178.0.2 ECMP,in-hw 4092 192.178.0.1 0