VRRP – using 2651xm

by Cyrus Lok on Monday, August 30, 2010 at 11:22pm

No worries if 3550 does not support VRRP.

2651xm real router does!

2651xm-1#sh ip int bri

Interface                  IP-Address      OK? Method Status                Protocol

FastEthernet0/0            172.16.1.1      YES NVRAM  up                    down

FastEthernet0/1            unassigned      YES NVRAM  administratively down down

Note: If I use real address as the VRRP ip address then the router becomes the master router for VRRP, priority has no effect on this master router, if VRRP ip address is not using a real address instead a virtual address then router with the highest priority becomes the master router.

2651xm-1(config)#int fa0/0

2651xm-1(config-if)#vrrp 1 ip 172.16.1.1

(Real router’s ip address)

2651xm-1(config-if)#vrrp 1 priority 150

% Priority change will have no effect whilst interface is VRRP address owner

(This is what happens if you use real ip address as VRRP IP address, priority value has no effect)

2651xm-1(config-if)#vrrp 1 timers advertise msec 500

(Default hello timer is 1s, VRRP only allows me to configure hello timer)

2651xm-1(config-if)#vrrp 1 preempt

2651xm-1(config-if)#vrrp 1 ?

authentication  Authentication

description     Group specific description

ip              Enable Virtual Router Redundancy Protocol (VRRP) for IP

preempt         Enable preemption of lower priority Master

priority        Priority of this VRRP group

shutdown        Disable VRRP Configuration

timers          Set the VRRP timers

track           Event Tracking

(Cisco routers do support VRRP authentication as opposed to the new VRRP standards)

VRRP can only track objects unlike HSRP which can track link and objects.

2651xm-1(config)#track 1 interface fa0/0 line-protocol

2651xm-1(config-track)#exit

2651xm-1(config-if)#vrrp 1 track 1 decrement 20

% tracking not supported on IP address owner

(Remember, I used real ip address, priority has no meaning)

2651xm-1#sh vrrp int fa0/0

FastEthernet0/0 – Group 1

State is Init

Virtual IP address is 172.16.1.1

Virtual MAC address is 0000.5e00.0101

Advertisement interval is 0.500 sec

Preemption enabled  Priority is 255 (cfgd 150)

Master Router is 172.16.1.1 (local), priority is 255

Master Advertisement interval is 1.000 sec

Master Down interval is 1.503 sec