We have 2 cisco 1921routers (R1 and R1) both have 2 interfaces Gi0/0 and Gi0/1. We have 2 cisco 2960G Ethernet switches S1 and S2 are connected to each other. Each router is connected to both Ethernet switches. On each router has Gi0/0 as the primary interface and Gi0/1 as backup interface. I am able to configure hsrp on primary interface but it does not allow me to configure same standby ip on backup interface.
Our intent is to provide fault tolerance on both router as well as Ethernet switch level.
R1-Gi0/0 -->S1 and R1-Gi0/1 -->S2
R2-Gi0/0 -->S1 and R2-Gi0/1 -->S2
interface GigabitEthernet0/0
backup interface GigabitEthernet0/1
ip address 192.168.101.2 255.255.255.0
standby 1 ip 192.168.101.1
standby 1 priority 101
standby 1 preempt
duplex auto
speed auto
interface GigabitEthernet0/1
ip address 192.168.101.2 255.255.255.0
standby 1 priority 102
standby 1 preempt
duplex auto
speed auto