Question

A network engineer configures IP SLA to track reachability of a primary WAN next-hop (10.1.1.2) and float a backup static route when it fails. The relevant configuration is:

ip sla 1
 icmp-echo 10.1.1.2
 frequency 5
 threshold 3000
 timeout 2000
track 1 ip sla 1 reachability

Users report that even during brief periods of high latency (round-trip around 2500 ms) on the primary link, the tracked object goes down and traffic fails over unnecessarily, then flaps back. The link itself never actually loses connectivity. Which change corrects this unnecessary failover behavior?

Accepted Answer

Increase the timeout value to a value greater than the observed round-trip latency (e.g., timeout 3000) so echoes are not declared lost during latency spikes.

Answer

Change the track statement to 'track 1 ip sla 1 state' so the delay threshold is used instead of reachability.

Answer

Lower the threshold to 1000 ms so the operation completes faster and stops timing out.

Answer

Increase the frequency to 30 seconds so the probe runs less often and avoids transient latency.