A network administrator is migrating a gateway configuration from VRRP to HSRP Group 1 on a Cisco router. Under the previous VRRP setup, the virtual IP address was configured to match the physical IPv4 address of router R1's GigabitEthernet0/1 interface (192.168.10.1/24). The administrator attempts to enter the command `standby 1 ip 192.168.10.1` under interface GigabitEthernet0/1 on R1. What is the outcome of executing this command on Cisco IOS?
- AThe router accepts the command and automatically sets R1's HSRP priority to 255 to designate it as the IP address owner.
- Cisco IOS rejects the command because HSRP virtual IP addresses must be distinct from any physical IP address configured on the router interfaces.Answer
- CThe router accepts the command, but R1 remains permanently in the Speak state due to a virtual IP conflict.
- DThe command is accepted only if preemption is manually disabled prior to executing the virtual IP assignment.
Answer
Cisco IOS rejects the command because HSRP virtual IP addresses must be distinct from any physical IP address configured on the router interfaces.
In Cisco IOS HSRP implementation, the virtual IP address must be an unassigned IP within the local subnet and cannot match the physical IP address of any participating router interface. Attempting to set the HSRP virtual IP to the router interface's physical IP results in an immediate CLI configuration error.
Step-by-Step Solution
Key Concept
HSRP Virtual IP Addressing Rules vs VRRP IP Address Ownership