How to Verify Default Passive Interfaces in Cisco Router
To verify that interfaces on your network have been set to passive, you could enter a network monitoring command such as show ip ospf interface, or you could verify the interfaces you enabled as active using a command such as show ip interface.
The following is an example of verifying passive interfaces in an OSPF network:
•
Enter the command show ip ospf interface to verify that all interfaces have been set as passive (see report indicating “No Hellos (Passive interface)”:
Router(config)#Â show ip ospf interface
Ethernet0 is up, line protocol is up
Internet Address 171.69.232.70/28, Area 4
Process ID 100, Router ID 171.69.232.70, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 171.69.232.70, Interface address 171.69.232.70
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
Suppress hello for 0 neighbor(s)
Serial0 is up, line protocol is up
Internet Address 172.24.101.14/30, Area 4
Process ID 100, Router ID 171.69.232.70, Network Type POINT_TO_POINT, Cost: 64
Transmit Delay is 1 sec, State POINT_TO_POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.24.101.15
Suppress hello for 0 neighbor(s)
TokenRing0 is up, line protocol is up
Internet Address 140.10.10.4/24, Area 0
Process ID 100, Router ID 171.69.232.70, Network Type BROADCAST, Cost: 6
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 171.69.232.70, Interface address 140.10.10.4
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
Suppress hello for 0 neighbor(s)
This is just one example of how to verify status of your network interfaces. Refer to the Cisco IOS Release 12.0 Network Protocols Configuration Guide, Part 1 and Cisco IOS Release 12.0 Network Protocols Command Reference, Part 1, for more information about monitoring your network interfaces.