Configuration on R5:
r5>en
R5#conf T
R5 (config) #inter f0/0
R5 (config-if) #ip address 192.168.10.10 255.255.255.0 Configure Port IP addresses
R5 (config-if) #no shut
R5 (config-if) #inter F0/1
R5 (config-if) #ip address 202.106.1.10 255.255.255.0
R5 (config-if) #no shut
R5 (config) #inter f0/0
R5 (config-if) #standby 1 IP 192.168.10.1 hot backup virtual gateway
R5 (config-if) #standby 1 priority 150 priority
R5 (config-if) #standby 1 preempt preemption
R5 (config-if) #standby 1 track FA0/1 10 monitoring port tracking minus priority
R5 (config-if) #ex
R5 (config) #ip route 0.0.0.0 0.0.0.0 202.106.1.1 default route next address
R6 configuration:
r6>en
R6#conf T
R6 (config) #inter f0/0
R6 (config-if) #ip address 192.168.10.11 255.255.255.0
R6 (config-if) #no shut
R6 (config-if) #inter F0/1
R6 (config-if) #ip address 202.106.10.10 255.255.255.0
R6 (config-if) #no shut
R6 (config) #inter f0/0
R6 (config-if) #standby 1 IP 192.168.10.1
R6 (config-if) #standby 1 priority 145
R6 (config-if) #standby 1 preempt
*mar 1 00:09:13.263:%cdp-4-duplex_mismatch:duplex mismatch discovered on fastethernet0/0 (not all DUPLEX), with R1 Fas TETHERNET1/4 (full duplex).
R6 (config) #ip Route 0.0.0.0 0.0.0.0 202.106.10.1
R6 (config) #inter f0/0
R6 (config-if) #speed 100
R6 (config-if) #duplex full