How to check active ospf broadcast network or configured interface in switch

[getaway51]

Hi,

I would like to know how to check all the networks or interfaces where ospf is activated and passive.

Thanks!

[Georg Pauwen]

Hello,

after issuing the command "show ip ospf interface' look for the line 'No Hellos (Passive interface)'. A passive interface does not send out Hellos...

GigabitEthernet0/1 is up, line protocol is up
Internet Address 20.20.20.1/30, Area 0, Attached via Network Statement
Process ID 1, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 1
Topology-MTID Cost Disabled Shutdown Topology Name
0 1 no no Base
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 1.1.1.1, Interface address 20.20.20.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
oob-resync timeout 40
Hello due in 00:00:01
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 1/2/2, flood queue length 0
Next 0x0(0)/0x0(0)/0x0(0)
Last flood scan length is 0, maximum is 0
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)

GigabitEthernet0/0 is up, line protocol is up
Internet Address 10.10.10.1/30, Area 0, Attached via Network Statement
Process ID 1, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 1
Topology-MTID Cost Disabled Shutdown Topology Name
0 1 no no Base
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 1.1.1.1, Interface address 10.10.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
oob-resync timeout 40
No Hellos (Passive interface)
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 1/1/1, flood queue length 0
Next 0x0(0)/0x0(0)/0x0(0)
Last flood scan length is 0, maximum is 0
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)

[omz]

To quickly check the interfaces in OSPF you can also use ..

R4#sh ip ospf int brief
Interface    PID   Area            IP Address/Mask    Cost  State Nbrs F/C
Lo0          1     0               4.4.4.4/32         1     LOOP  0/0
Et0/1        1     0               192.168.1.10/30    10    BDR   1/1
Et0/0        1     0               192.168.1.13/30    10    BDR   1/1
R4#

[omz]

To see all passive interfaces you can use .. 

R4#sh ip protocols
*** IP Routing is NSF aware ***

Routing Protocol is "application"
  Sending updates every 0 seconds
  Invalid after 0 seconds, hold down 0, flushed after 0
  Outgoing update filter list for all interfaces is not set
  Incoming update filter list for all interfaces is not set
  Maximum path: 32
  Routing for Networks:
  Routing Information Sources:
    Gateway         Distance      Last Update
  Distance: (default is 4)

Routing Protocol is "ospf 1"
  Outgoing update filter list for all interfaces is not set
  Incoming update filter list for all interfaces is not set
  Router ID 4.4.4.4
  Number of areas in this router is 1. 1 normal 0 stub 0 nssa
  Maximum path: 4
  Routing for Networks:
    192.168.1.0 0.0.0.255 area 0
  Routing on Interfaces Configured Explicitly (Area 0):
    Loopback0           <<<<< ip ospf 1 area 0 command on interface
  Passive Interface(s):
  Passive Interface(s):
    Ethernet0/1
    Ethernet0/2
    Ethernet0/3
    RG-AR-IF-INPUT1
    VoIP-Null0
  Routing Information Sources:
    Gateway         Distance      Last Update
    5.5.5.5              110      00:00:43
    1.1.1.1              110      10:06:03
    2.2.2.2              110      10:06:03
    3.3.3.3              110      10:06:03
  Distance: (default is 110)

R4#

or 

R4#sh ip protocols | b Passive
  Passive Interface(s):
    Ethernet0/1
    Ethernet0/2
    Ethernet0/3
    RG-AR-IF-INPUT1
    VoIP-Null0
  Routing Information Sources:
    Gateway         Distance      Last Update
    5.5.5.5              110      00:04:29
    1.1.1.1              110      10:09:48
    2.2.2.2              110      10:09:48
    3.3.3.3              110      10:09:48
  Distance: (default is 110)