VRRP-Backward Compatibility
This section contains VRRP Backward Compatibility configuration examples.
The backward compatibility feature which implements version 3 of VRRP protocol recognizes the presence of VRRP version 2 compatible routers in the network and performs all operations normally. This support is intended for upgrade scenarios and is not recommended for permanent deployments. This should only occur when a router is transitioning from VRRPv2 to VRRPv3.
VRRP Backward Compatibility is applicable only for VRRP IPv4.
Topology
R1
#configure terminal | Enter the Configure mode. |
(config)#interface xe1 | Enter Interface configuration mode. |
(config-if)#ip address 5.5.5.90/24 | Configure IP address on the interface. |
(config-if)#commit | Commit the candidate configuration to the running configuration. |
(config-if)#exit | Exit Router mode. |
(config)#router vrrp 1 xe1 | Configure VRRP on DUT with Virtual router Identifier as 1 on the interface xe1. |
(config-router)#virtual-ip 5.5.5.190 | Configure Virtual-IP address as the interface IP address of Owner which is not actually present in the LAN. |
(config-router)#v2-compatible | Enable the v2-compatible |
(config-router)#authentication text abcd | Configure the authentication text to specify that as simple text for vrrpv2 packets, accept only 8 characters |
(config-router)#enable | Enable VRRP session on DUT. |
(config-router)#commit | Commit the candidate configuration to the running configuration. |
(config-router)#exit | Exit Router mode. |
(config)#vrrp compatible-v2 enable | Enable VRRP-Backward compatibility feature on a VRRPv3 running router. |
(config-router)#commit | Commit the candidate configuration to the running configuration. |
(config-router)#exit | Exit Router mode. |
R2
#configure terminal | Enter the Configure mode. |
(config)# interface xe1 | Enter Interface configuration mode. |
(config-if)#ip address 5.5.5.100/24 | Configure IP address on the interface. |
(config-if)#commit | Commit the candidate configuration to the running configuration. |
(config-if)#exit | Exit Router mode. |
(config)#router vrrp 1 xe1 | Configure VRRP on DUT with Virtual router Identifier as 1 on the interface xe1. |
(config-router)#virtual-ip 5.5.5.190 | Configure Virtual-IP address as the interface IP address of Owner which is not actually present in the LAN. |
(config-router)#v2-compatible | Enable the v2-compatible |
(config-router)#authentication text abcd | Configure the authentication text to specify that as simple text for vrrpv2 packets, accept only 8 characters |
(config-router)#enable | Enable VRRP session on DUT. |
(config-router)#commit | Commit the candidate configuration to the running configuration. |
(config-router)#exit | Exit Router mode. |
Validation
R1
OcNOS#sh vrrp
VRRP Version: 3
VMAC enabled
Backward Compatibility enabled
Address family IPv4
VRRP Id: 1 on interface: xe1
State: AdminUp - Master
Virtual IP address: 5.5.5.190 (Not-owner)
Virtual MAC address is 0000.5e00.0101
Operational primary IP address: 5.5.5.90
Operational master IP address: 5.5.5.90
Priority is 100
Advertisement interval: 100 centi sec
Master Advertisement interval: 100 centi sec
Virtual router uptime: 0 hours 2 minutes 32 seconds (15200 centi sec)
Master uptime: 0 hours 2 minutes 28 seconds (14800 centi sec)
Accept mode: TRUE
Preempt mode: TRUE
Auth-type: simple text, String: abcd
Multicast membership on IPv4 interface xe1: JOINED
V2-Compatible: TRUE
R2
OcNOS#sh vrrp
VRRP Version: 3
VMAC enabled
Backward Compatibility disabled
Address family IPv4
VRRP Id: 1 on interface: xe1
State: AdminUp - Backup
Virtual IP address: 5.5.5.190 (Not-owner)
Virtual MAC address is 0000.5e00.0101
Operational primary IP address: 5.5.5.100
Operational master IP address: 5.5.5.90
Priority is 100
Advertisement interval: 100 centi sec
Master Advertisement interval: 100 centi sec
Virtual router uptime: 0 hours 1 minutes 11 seconds (7100 centi sec)
Skew time: 60 centi sec
Master Down Interval: 360 centi sec
Accept mode: TRUE
Preempt mode: TRUE
Auth-type: simple text, String: abcd
Multicast membership on IPv4 interface xe1: JOINED
V2-Compatible: TRUE
Last modified date: 08/28/2023