hostname Switch1
interface Vlan10
ip address 172.16.10.32 255.255.255.0
no ip redirects
standby 1 ip 172.16.10.110
standby 1 timers msec 200 msec 700
standby 1 preempt
hostname Switch2
interface Vlan10
ip address 172.16.10.33 255.255.255.0
no ip redirects
standby 1 ip 172.16.10.110
standby 1 timers msec 200 msec 750
standby 1 priority 110
standby 1 preempt
hostname Switch3
interface Vlan10
ip address 172.16.10.34 255.255.255.0
no ip redirects
standby 1 ip 172.16.10.110
standby 1 timers msec 200 msec 750
standby 1 priority 150
standby 1 preempt
Refer to the above. Three switches are configured for HSRP.
Switch1 remains in the HSRP listen state. What is the most likely cause of this status?
A.
This is normal operation.
B.
The standby group number does not match the VLAN number.
C.
IP addressing is incorrect.
D.
Priority commands are incorrect.
E.
Standby timers are incorrect.
Explanation:
This is expected behavior. When HSRP is configured on an interface, the router progresses
through a series of states before becoming active. This forces a router to listen for others in a
group and see where it fits into the pecking order. Devices participating in HSRP must progress
their interfaces through the following state sequence:
1. Disabled
2. Init
3. Listen
4. Speak
5. Standby
6. Active
Only the standby (the one with the second-highest priority) router monitors the hello message from
the active router. By default, hellos are sent every 3 seconds. If hellos are missed for the duration
of the holdtime timer (default 10 seconds, or three times the hello timer), the active router is
presumed to be down. The standby router is then clear to assume the active role. At that point, if
other routers are sitting in the Listen state, the next-highest priority router is allowed to become the
new standby router.
Reference:
CCNP BCMSN Official Exam Certification Guide, Fourth Edition, Chapter 13: Router, Supervisor,
and Power Redundancy, p. 318