Basic configuration steps for HSRP (Hot Standby Router Protocol)

In this post I am going to go over some HSRP – Hot Standby Router Protocol options and basic configuration steps. HSRP – Hot Standby Router Protocol in simple terms makes two Cisco routers with two different IP addresses look like one. You would need at least three (3) IP addresses to configure HSRP – Hot Standby Router Protocol. Each Cisco router will get an IP address and one IP address will be the virtual IP.

So lets take a look at the list of steps for configuring HSRP – Hot Standby Router Protocol. I am going to use Cisco 800 series router for this example. It has a total of 5 interfaces, 1 X WAN (fa4), 3 X LAN (fa0, fa1, fa2, fa3):

• Console into the router and switch to the “global exec” mode
• First type “enable” and then “conf t”
• Now you need to go to the interface configuration to finish rest of the HSRP setup

Router 1:
conf t
interface fa4
ip address 192.168.1.2 255.255.255.0
standby 1 ip 192.168.1.1 (This sets up the Virtual IP address)
standby version 2 (This will enable HSRP Version 2 not required)
standby 1 timers 15 30 (This specifies the Hello and router status timers)
standby 1 priority 100 (This specifies the priority of the router)
standby 1 preempt delay sync 30 (This will make the higher priority router active with a delay)
standby 1 track fastethernet4 (This will track the interface, in this case “fa4”)
—————————————————————————————————
Router 2
conf t
interface fa4
ip address 192.168.1.3 255.255.255.0
standby 1 ip 192.168.1.1 (This sets up the Virtual IP address)
standby version 2 (This will enable HSRP Version 2 not required)
standby 1 timers 15 30 (This specifies the Hello and router status timers)
standby 1 priority 100 (This specifies the priority of the router)
standby 1 preempt delay sync 30 (This will make the higher priority router active with a delay)
standby 1 track fastethernet4 (This will track the interface, in this case “fa4”)

Now you have both Cisco Routers configured for HSRP – Hot Standby Router Protocol. Next I would like to talk a little bit more about some command line options that I mentioned above to give a general idea of what they do:

Standby IP: This is the virtual IP address that all clients can use as their gateway.
Standby group#: You can create multiple groups of HSRP routers. One router can be an active router for one group and it can be a standby for another.
Standby Priority: This specifies the priority of each router in the standby configuration. Higher priority router will be the active router. If no priority is defined router with the highest IP address will be come the active router. Default Priority is 100 i.e; if you do not define it.
Preempt: This setting makes the router with the highest priority take over and become an active router.
Preempt Delay: Preempt delay setting is optional but you do want to fine tune it because of STP make sure that STP has time to converge on the switch and also that the standby router can populate the routes in its database.