A redundant gateway with VRRP
Same LAN, but this company wants an open standard. Configure VRRP group 1 with virtual IP 192.168.10.1 on both routers' Gi0/0:
- R2 is the Master this time (priority 120).
- R1 stays at the default priority.
- R2 tracks its uplink with track object 1 and lowers its priority by 30 when it's down.
How it works: this is VulnTech NetLab, a network simulator running in your browser. Click a device in the diagram to open its console and type commands, just like on real equipment (? shows help, Tab finishes a word). Click a cable to inspect it. Tasks tick themselves off as you complete them; questions are answered in the box under each task. Your work is kept if you reload; Reset starts the network over.
Solution explanation
The track object watches Gi0/1's line protocol; the VRRP group uses it. If R2's uplink fails, its priority drops to 90, below R1's 100, and because VRRP pre-empts by default R1 takes over at once. With HSRP you'd have to add preempt yourself.
Show solution
[R2]
enable
configure terminal
track 1 interface g0/1 line-protocol
interface g0/0
vrrp 1 ip 192.168.10.1
vrrp 1 priority 120
vrrp 1 track 1 decrement 30
end
[R1]
enable
configure terminal
interface g0/0
vrrp 1 ip 192.168.10.1
end
show vrrp brief
[PC2]
ping -c 3 8.8.8.8