OSPF Route ... Time stamp meaning?

[avinashmahanty]

Hi All,

While troubleshooting a network issue i noticed the time stamps for each route in the Routing table. We are running OSPF and would like to know what events would cause the time stamps of each routes in the routing table change.

As per my understanding,

- the time stamp indicates since when a particular route has been injected into the routing table by OSPF.

- events such as OSPF peers down, SPF recalculation due to topology change will cause the time stamps to change.

As an example, below is a route present in the routing table.Time stamp for this route is 14:23:40 which tells me the route has been present in the routing table since the past 14 hours 23 minutes and 40 seconds.

O E1    192.x.x.x/24 [110/5180] via 10.1.2.129, 14:23:40, Vlan108

Is my understanding correct? What else could cause the time stamps of routes to change?

Looking forward to other memebers thoughts.

thx,

[Reza Sharifi · Accepted solution]

Hi,

Your understanding is correct. usually, after 24 hours the router show only the day and the hour and then the week and the day

example:

O E1    192.x.x.x/24 [110/5180] via 10.1.2.129, 5d21h, Vlan108

O E1    192.x.x.x/24 [110/5180] via 10.1.2.129, 1w1d, Vlan108

HTH

[Abzal · Accepted solution]

Hi,

Yes, it's correct. It means that the route has been present in the routing table for 14 h 23 min 40 sec.

http://keepingitclassless.net/2011/07/the-anatomy-of-show-ip-route/

Hope it will help.

Best regards,
Abzal

[Gabriel Hill · Accepted solution]

Hello Avinash,

You're understanding is correct. Anything that would cause to route to be removed from the routing table will cause the timestamp to be reset.

[avinashmahanty]

Thanks everyone for reinforcing my understanding as had a very peculiar issue.