Configuring Passive Interface suppresses routing updates on all interfaces.
Type the following:
iS5comm# configure terminal
iS5comm(config)# router ospf
iS5comm(config-if)# passive-interface default
All OSPF interfaces created after the execution of this command will be passive. This is useful for an Internet service provider (ISP) and large enterprise networks where many of the distribution routers have more than 200 interfaces.
iS5comm(config-if)# network 10.4.0.1 area 0.0.0.0
iS5comm(config-if)# end
Type the following:
iS5comm# show ip ospf interface vlan 1
vlan1 is line protocol is up
Internet Address 10.4.0.1, Mask 255.255.0.0, Area 0.0.0.0
AS 1, Router ID ID 10.10.2.1, Network Type BROADCAST, Cost 1
Transmit Delay is 1 sec, State 2, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
No Hellos (Passive interface)
Neighbor Count is 0, Adjacent neighbor count is 0
Type the following:
iS5comm(config-if)# no network 10.4.0.1 area 0.0.0.0
iS5comm(config-if)# no passive-interface default
It is also possible to suppress routing updates on a specified interface.
Type the following:
iS5comm# configure terminal
iS5comm(config)# router ospf
iS5comm(config)# interface vlan 1
iS5comm(config-if)# network 10.4.0.1 area 0.0.0.0
iS5comm(config-if)# passive-interface vlan 1
iS5comm(config-if)# end
Type the following:
iS5comm# show ip ospf interface vlan 1
vlan1 is line protocol is up
Internet Address 10.4.0.1, Mask 255.255.0.0, Area 0.0.0.0
AS 1, Router ID ID 10.10.2.1, Network Type BROADCAST, Cost 1
Transmit Delay is 1 sec, State 2, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
No Hellos (Passive interface)
Neighbor Count is 0, Adjacent neighbor count is 0
Type the following:
iS5comm(config-if)# no passive-interface vlan 1