on R1 
conf t
ip route 0.0.0.0 0.0.0.0 196.10.0.2 track 1
ip route 0.0.0.0 0.0.0.0 196.30.0.2 track 2

ip sla 1
icmp-echo 196.20.0.2 source-interface fa1/0
exit

ip sla 2
icmp-echo 196.40.0.2 source-interface fa1/1
exit

ip sla schedule 1 life forever start-time now
ip sla schedule 2 life forever start-time now

track 1 ip sla 1 reachability
exit
track 2 ip sla 2 reachability
end

conf t
ip route 196.20.0.0 255.255.255.0 196.10.0.2
ip route 196.40.0.0 255.255.255.0 196.30.0.2
end


on R2 
conf t
ip route 4.4.4.4 255.255.255.255 196.20.0.2
ip route 156.10.0.0 255.255.255.0 196.10.0.1
end


on R3 
conf t
ip route 4.4.4.4 255.255.255.255 196.40.0.2
ip route 156.10.0.0 255.255.255.0 196.30.0.1
end


on R4 
conf t

# Default routes
ip route 0.0.0.0 0.0.0.0 196.20.0.1
ip route 0.0.0.0 0.0.0.0 196.40.0.1

# SLA
ip sla 1
icmp-echo 196.20.0.2 source-interface fa1/0
exit

ip sla 2
icmp-echo 196.40.0.2 source-interface fa1/1
exit

ip sla schedule 1 life forever start-time now
ip sla schedule 2 life forever start-time now

track 1 ip sla 1 reachability
exit
track 2 ip sla 2 reachability
end

# Loopback + return routes
conf t
interface loopback0
ip address 4.4.4.4 255.255.255.255
exit

ip route 196.10.0.0 255.255.255.0 196.20.0.1
ip route 196.30.0.0 255.255.255.0 196.40.0.1
end

