OSPF routing information sources age?

[WallaceVanDunk1494]

I have some gateways that simply do not exist anymore in my network, but they still show up when I issue the "show ip protocols" command and I'm wondering why.  Is there a way to clean these out or will they remove themselves eventually?

Routing Information Sources:
    Gateway         Distance      Last Update
    10.5.97.1            110      4d01h
    10.5.255.1           110      00:10:23
    10.5.255.2           110      4d01h
    10.5.255.6           110      00:10:23
    10.8.255.2           110      3w0d
  Distance: (default is 110)

I tired clearing all options within the "clear ip ospf" command...traffic,events,process, etc.  

10.5.97.1 was an interface on the firewall that literally doesn't exist anymore, 10.5.255.2 is a directly connected portchannel on the router that excerpt came from, and 10.8.255.2 is a loopback that used to be used for ospf but isn't anymore

[Richard Burts · Accepted solution]

The output indicates last update from 10.5.97.1 was 4 days ago. If it no longer exists when did it go away? And how did it go away? 10.8.255.2 last update was 3 weeks ago. When did it go away? I would have thought that clearing the OSPF process might have helped. If it did not then perhaps you might try a router reload.

[Giuseppe Larosa]

Hello @WallaceVanDunk1494 ,

being the output of show ip protocols you could try to use

clear ip route *

to see if the old entries are cleared.

In any case

show ip ospf neighbor detail

show ip ospf database

provide you a lot of current information about OSPF activity.

If even clear ip route * does not purge these old entries as a last resort you could reload the router.

The meaning of that list is likely an historical recording.

Hope to help

Giuseppe

[Ruben Cocheno]

@WallaceVanDunk1494 

that is a bit strange, if you do not have those sources active on the network they should go away. Do they stay even if you reboot? if yes, give a look on adjance devices and check if the have the same info.

[WallaceVanDunk1494]

Clear ip route * didn't help.  OSPF database doesn't show anything odd.  Neither does ospf neighbor detail.

core#sh ip ospf nei det
 Neighbor 10.5.255.6, interface address 10.5.255.6
    In the area 0 via interface Port-channel2
    Neighbor priority is 10, State is FULL, 6 state changes
    DR is 10.5.255.5 BDR is 10.5.255.6
    Options is 0x12 in Hello (E-bit, L-bit)
    Options is 0x52 in DBD (E-bit, L-bit, O-bit)
    LLS Options is 0x1 (LR)
    Dead timer due in 00:00:02
    Neighbor is up for 01:56:56
    Index 1/1, retransmission queue length 0, number of retransmission 4
    First 0x0(0)/0x0(0) Next 0x0(0)/0x0(0)
    Last retransmission scan length is 1, maximum is 2
    Last retransmission scan time is 0 msec, maximum is 0 msec
 Neighbor 10.5.255.1, interface address 10.5.255.1
    In the area 0 via interface Port-channel1
    Neighbor priority is 150, State is FULL, 6 state changes
    DR is 10.5.255.2 BDR is 10.5.255.1
    Options is 0x2 in Hello (E-bit)
    Options is 0x2 in DBD (E-bit)
    Dead timer due in 00:00:02
    Neighbor is up for 00:21:48
    Index 2/2, retransmission queue length 0, number of retransmission 1
    First 0x0(0)/0x0(0) Next 0x0(0)/0x0(0)
    Last retransmission scan length is 2, maximum is 2
    Last retransmission scan time is 0 msec, maximum is 0 msec

core#sh ip ospf dat

            OSPF Router with ID (10.5.255.2) (Process ID 1)

                Router Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum Link count
10.5.255.1      10.5.255.1      1361        0x80000004 0x00B755 1
10.5.255.2      10.5.255.2      1238        0x80000A7A 0x00A52F 6
10.5.255.6      10.5.255.6      1192        0x800000B6 0x00C31C 3

                Net Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum
10.5.255.2      10.5.255.2      1355        0x80000004 0x006195
10.5.255.5      10.5.255.2      1238        0x80000004 0x008965

                Type-5 AS External Link States

Link ID         ADV Router      Age         Seq#       Checksum Tag
0.0.0.0         10.5.255.1      1364        0x80000001 0x00BEF9 0

I see the same old entries on my access switch as well.  I guess I'll try a reload next.  Thanks for the replies.  I'll post back with results.

[Giuseppe Larosa]

Hello @WallaceVanDunk1494 ,

my suggestion to use

show ip ospf neighbor detail

show ip ospf database

was intended to give you the correct and updated information in a different way.

By the way, I use these two commands rather then then the output of show ip protocols to check the status of OSPF.

I'm glad that reloading solved the issue, but this is not normal as it looks like that OSPF is not able to remove entries in the show ip protocols routing sources list.

Hope to help

Giuseppe

[WallaceVanDunk1494]

Reloading the switches did the trick.  Seems odd that that's the only recourse to clear the old gateways out though.  Can't be practical in most production environments.

Thanks for all the replies and for suggesting the reload.

[Richard Burts]

I am glad that my suggestion about reloading turned out to be the solution. It does seem a bit odd that this information is not dynamically updated.  In terms of whether it is practical or not, in most production networks there are few changes in gateways. So the fact that this seems to be a historical view rather than a current environment view may not have a lot of impact on its practicality. Thank you for marking this question as solved. This will help other participants in the community to identify discussions which have helpful information. This community is an excellent place to ask questions and to learn about networking. I hope to see you continue to be active in the community.