Route selection by host reachability with Cisco SLA

Goal:

Monitor an Internet address and change default route if that address is unreachable.

Remote IP to Monitor: 4.4.4.4

Primary Provider Gateway: 1.1.1.2

Backup Provider Gateway: 2.2.2.2

Config:

ip route 4.4.4.4 255.255.255.255 1.1.1.2

ip sla 1
icmp-echo 4.4.4.4
ip sla schedule 1 life forever start-time now

track 1 ip sla 1 reachability

ip route 0.0.0.0 0.0.0.0 1.1.1.2 track 1
ip route 0.0.0.0 0.0.0.0 2.2.2.2 200

Show Commands:

router#sh ip sla statistics
IPSLAs Latest Operation Statistics
IPSLA operation id: 1
Latest RTT: 1 milliseconds
Latest operation start time: *16:00:53.925 UTC Tue Jan 27 2009
Latest operation return code: OK
Number of successes: 33
Number of failures: 0
Operation time to live: Forever

router#sh track 1
Track 1
IP SLA 1 reachability
Reachability is Up
1 change, last change 11:14:51
Latest operation return code: OK
Latest RTT (millisecs) 1
Tracked by: