Examkin

Question

Difficulty: MediumFirst Hop Redundancy Protocols (HSRP and VRRP)

An engineer executes the following interface configuration on a Cisco IOS router:

text
R1(config)# interface GigabitEthernet0/0
R1(config-if)# ip address 10.1.1.1 255.255.255.0
R1(config-if)# standby 10 ip 10.1.1.1

What is the outcome of issuing the `standby 10 ip 10.1.1.1` command?

  1. Cisco IOS rejects the command because HSRP virtual IP addresses cannot match the physical IP address assigned to an interface.Answer
  2. B
    The command is accepted, and R1 automatically assumes the Active state with an operational priority of 255.
  3. C
    The command is accepted, but R1 remains stuck in the Speak state until a second router joins HSRP group 10.
  4. D
    The command is accepted, and Cisco IOS automatically enables HSRP preemption for group 10.

Answer

Cisco IOS rejects the command because HSRP virtual IP addresses cannot match the physical IP address assigned to an interface.
In Hot Standby Router Protocol (HSRP), the virtual IP address must be unique within the subnet and cannot be identical to the physical IP address assigned to any interface of participating routers. When attempting to configure an HSRP virtual IP address that matches an existing interface IP address, Cisco IOS rejects the command with an explicit error.

Step-by-Step Solution

1
Analyze the interface IP configuration and the requested HSRP virtual IP.
The physical interface IP is set to 10.1.1.1/24, and the HSRP command attempts to assign 10.1.1.1 as the virtual IP address for HSRP group 10.
Identifying overlapping IP configurations is necessary to determine protocol compliance.
2
Compare HSRP rules against VRRP rules regarding IP address ownership.
In VRRP, a router can be the IP address owner and use its physical IP as the virtual IP (raising priority to 255). In HSRP, the virtual IP address MUST be an unused IP address within the subnet and cannot match any router's physical interface IP.
HSRP implementation rules require an unused virtual IP address on the subnet.
3
Determine CLI output behavior.
Cisco IOS displays an error message rejecting the `standby 10 ip 10.1.1.1` command.
Entering a matching IP address violates HSRP address assignment rules.

Key Concept

HSRP Virtual IP Address Constraints vs VRRP IP Owner Rules
Estimated Time:1m 0s
Rate this question

Topics

First Hop Redundancy Protocols (HSRP and VRRP)

More questions from this topic