I have a Cisco IR829 with cellular, Wireless and LAN interfaces. I want to use the cellular interface as the Primary and if that fails then use the Wireless interface which is connected to the customers network, as a last resort the local LAN. Only fail to the LAN if both the Cellular and Wireless interfaces fail to reach the internet. Can I use IP SLA to track multiple interfaces?
See config below:
ip route 0.0.0.0 0.0.0.0 Cellular0 track 1
ip route 0.0.0.0 0.0.0.0 wlan-ap0 track 2
ip route 0.0.0.0 0.0.0.0 GigabitEthernet0 dhcp 20
ip sla 1
icmp-echo 22.214.171.124 source-interface Cellular0
ip sla 2
icmp-echo 126.96.36.199 source-interface wlan-ap0
ip sla schedule 1 life forever start-time now
track 1 ip sla 1 reachability
track 2 ip sla 2 reachability
track 3 list boolean and
Does the above config look right?
You will want to add an metric value to the track 2 static route otherwise it will be installed alongside the primary static route.
! ip route 0.0.0.0 0.0.0.0 wlan-ap0 2 track 2 ip route 0.0.0.0 0.0.0.0 GigabitEthernet0 dhcp 3 !
Also keep the metric of the last static route below the default AD for EIGRP summary routes (5).
The idea is to have a sequential failover. If the primary route fails, the secondary takes over. If BOTH routes fail, the tertiary will take over.
You might want to check if this works as designed before deploying.
As @Georg Pauwen points out, configuring static routes with incrementing metrics which themselves have tracks states of true will ensure that only one route will be installed at a time.
you might want to put the below EEM script into your config as well, which clears the current, active NAT translations in case of a failover, so you don't have to wait for the NAT entries to time out:
event manager applet CLEAR_NAT
event track 3 state any
action 1.0 cli command "enable"
action 2.0 cli command "clear ip nat translation *"