Here you go:

Router-F#sh ip os int brief

^

% Invalid input detected at '^' marker.

Router-F#sh ip ospf neigh

Neighbor ID Pri State Dead Time Address Interface

222.1.7.1 1 FULL/BDR 00:00:39 10.4.4.7 TokenRing0

222.1.8.1 1 FULL/DR 00:00:35 10.4.4.8 TokenRing0

222.1.5.1 1 FULL/ - 00:00:37 215.0.0.5 Serial0

Router-F#

Router-G>sh ip os int brief

^

% Invalid input detected at '^' marker.

Router-G>sh ip ospf neigh

Neighbor ID Pri State Dead Time Address Interface

222.1.6.1 1 FULL/DROTHER 00:00:39 10.4.4.6 TokenRing0

222.1.8.1 1 FULL/DR 00:00:35 10.4.4.8 TokenRing0

Router-G>

Router-E#sh ip ospf int brief

^

% Invalid input detected at '^' marker.

Router-E#

Here's the IOS versions we're running:

Router E:

IOS (tm) 2500 Software (C2500-I-L), Version 12.0(8), RELEASE SOFTWARE (fc1)

System image file is "flash:c2500-i-l.120-8.bin"

Router F:

IOS (tm) 2500 Software (C2500-JK8OS-L), Version 12.2(1d), RELEASE SOFTWARE (fc1)

System image file is "flash:/c2500-jk8os-l.122-1d.bin"

Router G:

IOS (tm) 2500 Software (C2500-JK8OS-L), Version 12.2(1d), RELEASE SOFTWARE (fc1)

System image file is "flash:/c2500-jk8os-l.122-1d.bin"

Very old software :)

Try show ip ospf interface

Yeah they're all 2500's (as I guess you could tell from the system image filename).

Router-E>sh ip ospf int

Serial1 is up, line protocol is up

Internet Address 215.0.0.5/30, Area 1

Process ID 100, Router ID 222.1.5.1, 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 00:00:01

Neighbor Count is 1, Adjacent neighbor count is 1

Adjacent with neighbor 222.1.6.1

Suppress hello for 0 neighbor(s)

Router-F>sh ip ospf int

Loopback0 is up, line protocol is up

Internet Address 222.1.6.1/24, Area 0

Process ID 100, Router ID 222.1.6.1, Network Type LOOPBACK, Cost: 1

Loopback interface is treated as a stub Host

TokenRing0 is up, line protocol is up

Internet Address 10.4.4.6/24, Area 0

Process ID 100, Router ID 222.1.6.1, Network Type BROADCAST, Cost: 6

Transmit Delay is 1 sec, State DROTHER, Priority 1

Designated Router (ID) 222.1.8.1, Interface address 10.4.4.8

Backup Designated router (ID) 222.1.7.1, Interface address 10.4.4.7

Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5

Hello due in 00:00:08

Index 1/1, flood queue length 0

Next 0x0(0)/0x0(0)

Last flood scan length is 0, maximum is 2

Last flood scan time is 0 msec, maximum is 4 msec

Neighbor Count is 2, Adjacent neighbor count is 2

Adjacent with neighbor 222.1.7.1 (Backup Designated Router)

Adjacent with neighbor 222.1.8.1 (Designated Router)

Suppress hello for 0 neighbor(s)

Serial0 is up, line protocol is up

Internet Address 215.0.0.6/30, Area 1

Process ID 100, Router ID 222.1.6.1, 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 00:00:09

Index 1/3, flood queue length 0

Next 0x0(0)/0x0(0)

Last flood scan length is 2, maximum is 4

Last flood scan time is 0 msec, maximum is 4 msec

Neighbor Count is 1, Adjacent neighbor count is 1

Adjacent with neighbor 222.1.5.1

Suppress hello for 0 neighbor(s)

Router-F#

Router-G>sh ip ospf int

Serial0 is down, line protocol is down

Internet Address 215.0.0.13/30, Area 0

Process ID 100, Router ID 222.1.7.1, Network Type POINT_TO_POINT, Cost: 64

Transmit Delay is 1 sec, State DOWN,

Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5

TokenRing0 is up, line protocol is up

Internet Address 10.4.4.7/24, Area 0

Process ID 100, Router ID 222.1.7.1, Network Type BROADCAST, Cost: 6

Transmit Delay is 1 sec, State BDR, Priority 1

Designated Router (ID) 222.1.8.1, Interface address 10.4.4.8

Backup Designated router (ID) 222.1.7.1, Interface address 10.4.4.7

Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5

Hello due in 00:00:00

Index 1/1, flood queue length 0

Next 0x0(0)/0x0(0)

Last flood scan length is 0, maximum is 1

Last flood scan time is 0 msec, maximum is 0 msec

Neighbor Count is 2, Adjacent neighbor count is 2

Adjacent with neighbor 222.1.6.1

Adjacent with neighbor 222.1.8.1 (Designated Router)

Suppress hello for 0 neighbor(s)

Router-G>

As I presumed, Router G does not have the loopback under the OSPF process.

As for having the LAN subnet in Area 1 on Router F, that's Router F way of announcing that subnet to Router E as an IA route.

HTH,

Please rate helpful posts

Well, I TOLD you Router G didn't have the loopback under the OSPF process (as you can tell from F's routing table, where H's loopback is present and G's isn't). So, why is G's loopback appearing as a Link ID in Router F's database?

For the LAN/Area 1 stuff - This is where it lists the links it's advertising outbound into that area? I thought it was where it listed the links it receives FROM that area.

Ah yes, just as I meant to say :-P

See, I'm still pretty new to interarea OSPF; so I guess part of why I'm confused is that you said above that "Remember, the OSPF Router ID is selected when enabling OSPF process but it does not automatically advertise the interface into OSPF. The loopback must be included in the network statement to be advertised as well."

So, since Router G/7's loopback wasn't included I didn't expect to see that loopack address as a Link ID in the Router Link States box. I don't mind seeing it as the Adv Router ID, I just didn't think that loopack address was something it would be Adv'ing.

So, the router ID of a neighbor router automatically becomes a Link ID, even if it's the address of a non-participating interface?