error messages "service_maxage: Trying to delete MAXAGE LSA"on the ospf

[burdog]

Hi...

My name is Choi tae young.

I'm sorry. My english write skill is very low.

My site running the ospf routing protocol.

"Debug ip ospf event" command excute on the backbone rotuer(7507).

Often ouput the event message that "service_maxage: Trying to delete MAXAGE LSA"

Why often output the messages ... ?

Thank you for reading my messages.

[Richard Burts]

This is a normal part of OSPF and is not an error. One of the ways that OSPF assures that the content of the Link State Data Base is current and correct is to assign an age to an LSA when the LSA is created and to increment the age while the LSA is in the data base. OSPF expects the LSA to be refreshed periodically. One of the functions within OSPF is to examine the entries in the data base and look for entries whose age is approaching the limit set by the maxage parameter. When OSPF finds an entry that has gotten to maxage, OSPF will delete that entry from the data base so that it is no longer making routing decisions on possibly outdated information.

[burdog]

Thank you for your reply message.

My network configuration is very difficult.

Last two months migration the routing protocol of the network from EIGRP to OSPF.

One of the importants the network issues are loss the routing table at the specific site very often.

So i verify the related information of the ospf.

"show ip ospf"

result is the follow...

SPF algorithm last executed 00:00:09.396 ago

SPF algorithm executed 8768 times

increase the number of SPF algorithm excuted and

last excuted not continue so long interval.

Why did problem occur...?

[Richard Burts]

The SPF has executd 8768 times - in what period of time?

It looks like SPF is running a lot. This is an indicator that something in your network is not stable. Do you have interfaces that flap frequently or womething like that?

are you using the option in OSPF to log-adjacency-change ? This will help show whether the neighbor relationship is stable or not.

to further investigate the neighbor adjacency you can turn on debug ip ospf adj.

to find out more about how often and why the SPF is executing I would suggest that you use debug ip ospf spf.

Hopefully this will give you more information to understand what is going on in your network.

[burdog]

Thank you.

Have a nice day.