HSRP: Priority and Preempt
The backup gateway stayed active after the preferred router came back. Diagnose it and fix it yourself, live, right below.
Symptom
The backup gateway is active after recovery even though the preferred router is healthy. Read HSRP state, priorities, and preempt behavior.
Your mission
Prove the cause, then fix it
Format
Guided CLI investigation
Investigate before you configure.
Use the CLI evidence to isolate the fault, make the smallest safe correction, then verify the network state changed.
Observe the symptom and link state.
Diagnose by comparing the protocol evidence.
Verify the expected device state and confirm the original symptom is resolved.
Console access: R1 · R2
This workspace stacks for portrait phones. Rotate to landscape for the full split-screen console.
Need a hint?
Reveal the root cause when you're ready.
Try the investigation first, then use this as your escape hatch, not a dead end.
Lab debrief
Turn the session into a repeatable troubleshooting pattern.
Use this reference after your attempt: first explain the symptom, then verify the evidence, then confirm the repair.
The problem
R1 was intended to be the active HSRP gateway. After a maintenance event R2 became active; when R1 returned with the higher priority, it stayed standby because preempt is not configured.
What you'll practice
- Read HSRP active and standby state
- Interpret priority
- Explain preempt
- Verify the virtual gateway remains reachable during role changes
The topology
Two routers connect to a common user VLAN and upstream network, sharing one HSRP virtual IPv4 address.
Commands to run yourself
The real diagnostic commands for this lab, copy-paste ready. Run these in the same order to reproduce the investigation on your own session.
show standby briefshow standbyping <virtual-ip>Frequently asked
Why doesn't the higher-priority router just take back Active automatically?
Priority alone only decides who wins an initial election. Once another router has already become active, HSRP requires the preferred router to have `preempt` configured before it will interrupt a working active router and reclaim the role.
Ready to run this lab yourself?
No setup, no image sourcing. Book a session or ask for a live demo.