Cisco CCNA (200-301)IP ConnectivityMedium
Two routers, R1 and R2, run HSRP for the 10.10.10.0/24 VLAN. R1 has priority 150 and is currently Active. R2 has priority 100 with default preempt settings. R1 experiences an interface failure and recovers a few minutes later. What will happen to the Active role after R1 recovers?
- ABoth routers become Active simultaneously, causing a split-brain condition
- BR1 becomes the new Standby router and stays that way permanently
- CR2 remains Active because preempt is not enabled on R1 by default
- DR1 automatically becomes Active again immediately because it has higher priority
Show answer & explanationAnswer & explanation
Correct answer: C. R2 remains Active because preempt is not enabled on R1 by default
HSRP does not preempt by default; even though R1 has a higher priority, it will not reclaim the Active role automatically once R2 has taken over unless 'standby preempt' is explicitly configured on R1.
Why the other options are wrong
- A. HSRP normally prevents split-brain by tracking hello/hold timers; simultaneous Active is not the expected default outcome.
- B. R1 will become Standby after recovery, but that is not because it is 'permanent'; it simply lacks preempt to reclaim Active.
- D. Without the preempt command configured, higher priority alone does not force a role change back.
HSRP Preempt
A configuration option that allows a router with a higher HSRP priority to take back the Active role after recovering from a failure.
- Preempt is disabled by default in HSRP
- Command: standby <group> preempt
- Without preempt, the current Active router keeps its role even if a higher-priority router returns
Memory trick: No preempt, no comeback: the throne stays with whoever's sitting.