Can 2 HSRP groups track the same WAN interface ?

[anish.antony]

Hi

I have a Cisco 1921 Router

The Gig 0/0 interface is been sub interfaced for 2 vlans 

Gig 0/1 is the WAN interface 

I want to have a redundancy for the WAN link which i am planning to achieve by having another Cisco 877 router with an ADSL link.

I will run HSRP and track the primary WAN interface of the main router.

But since there are 2 VLANS using the internet connection i am bit confused how i should implement HSRP

Can 2 HSRP groups track the same WAN interface  ?

Config on the subinterfaces of main router 

interface GigabitEthernet0/0.10

encapsulation dot1Q 10

ip address 192.168.1.1 255.255.255.0

ip helper-address 192.16.1.2

standby 1 ip 192.168.1.10

standby 1 priority 150

standby 1 preempt

standby 1 track dialer1 60 

ip nat inside

ip virtual-reassembly in

ip policy route-map proxy-redir

end

interface GigabitEthernet0/0.20

encapsulation dot1Q 20

ip address 192.168.2.1 255.255.255.0

standby 2 ip 192.168.2.10

standby 2 priority 150

standby 2 preempt

standby 2 track dialer1 60 

ip nat inside

ip virtual-reassembly in

ip policy route-map proxy-redir

end

[Philip D'Ath]

Yes, two different HSRP groups can track the same interface.

Note that the priority of 150 is quite high.  By default the interface failure will decrement it 10.  So you will need to use a high priority on the other router as well.  To keep things simple I suggest you use a priority of 105 on this router, and leave it on the default of 100 on the other router.

[anish.antony]

Hi Philip

Thanks for your feedback

You are right as i tested the scenario and was positive in my lab.

Although I noticed that to get that working i need to put the preempt command on both routers

Cheers,

Anish

[Philip D'Ath · Accepted solution]

Correct. "preempt" causes the router with the highest priority to take over immediately.

[Philip D'Ath]

ps. If you feel it is right could you rate my answer or mark it as correct?  :-)