On live monitoring of routing table changes during vty session:
1. Set logging level to debugging for vty sessions
conf t
logging monitor debugging
end
2. Turn on display of logging for current vty session and next turn on ip routing table debugging
terminal monitor
debug ip routing
3. To turn off display of logging for current vty session and turn off debugging
terminal no monitor
no debug ip routing
example:
Router(config)#ip route 0.0.0.0 0.0.0.0 192.168.0.1 name DEFAULT-GW Router(config)# *Oct 21 06:04:07.822: RT: add 0.0.0.0/0 via 192.168.0.1, static metric [1/0] *Oct 21 06:04:07.822: RT: NET-RED 0.0.0.0/0 *Oct 21 06:04:07.822: RT: default path is now 0.0.0.0 via 192.168.0.1 *Oct 21 06:04:07.822: RT: new default network 0.0.0.0 *Oct 21 06:04:07.822: RT: NET-RED 0.0.0.0/0 Router(config)#no ip route 0.0.0.0 0.0.0.0 192.168.0.1 Router(config)# *Oct 21 06:04:20.810: RT: del 0.0.0.0 via 192.168.0.1, static metric [1/0] *Oct 21 06:04:20.810: RT: delete network route to 0.0.0.0 *Oct 21 06:04:20.810: RT: NET-RED 0.0.0.0/0 *Oct 21 06:04:20.810: RT: NET-RED 0.0.0.0/0