I want to setup two routers in an HSRP group. To not waste 2 IPs within every customer subnet, I would like to have private IPs on the real interfaces and an official IP as the standby IP.
Here's my current HSRP setup of the first router that reflects what I want to do:
--snip---------- interface GigabitEthernet0/3 ip address 192.168.100.1 255.255.255.192 standby 1 ip 81.xx.xx.1 standby 1 preempt
ip route 81.xx.xx.0 255.255.255.192 GigabitEthernet0/3
This is not working the way I thought it should be.
# ping 192.168.100.1 -> WORKS # ping 81.xx.xx.1 -> WORKS # ping 81.xx.xx.2 -> FAILS
As soon as I try to ping a host that is connected via Layer 2 to GigabitEthernet0/3, it fails. Though, 81 is pingable when 81.xx.xx.1 is configured as real ip address on the router.
# show arp Protocol Address Age (min) Hardware Addr Type Interface ... Internet 81.xx.xx.1 - 0000.0c07.ac01 ARPA GigabitEthernet0/3 Internet 81.xx.xx.2 2 0050.da20.xxxx ARPA GigabitEthernet0/3 ...
# show standby GigabitEthernet0/3 - Group 1 State is Active 5 state changes, last state change 18:28:04 Virtual IP address is 81.xx.xx.1 Active virtual MAC address is 0000.0c07.ac01 Local virtual MAC address is 0000.0c07.ac01 (default) Hello time 3 sec, hold time 10 sec Next hello sent in 1.372 secs Preemption enabled Active router is local Standby router is unknown Priority 100 (default 100) IP redundancy name is "hsrp-Gi0/3-1" (default)
I found the following post about it, which says it is possible to use private IPs, but it's a hassle to set this up.I don't know what's additionally required, besides setting an ip route for 81.xx.xx.0 to be able to ping 81.xx.xx.2 from the router.