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Interface OSPF question and Something Wrong With GNS3

hitmen

If i assign a high interface loopback number but DONT assign it to an OSPF area

e.g

int lo30
ip add 172.1.1.1 255.255.255.255

BUT

I dont use network 172.1.1.1 0.0.0.0 area 0

in that case will this ip be assigned as router-id ??

I seem to have problems with GNS3. Using clear ip ospf process does not reset the router id.

Anyone experiencing the same thing?

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Comments

paq7512

That should be the router id if you did not use the router-id command in OSPF or that is the highest loopback address on that router.

Mrock4

Yup, the highest loopback will be used as paq7512 said, and it does NOT have to be advertised into any OSPF process for it to use that as the router-id.

networker050184

Clearing the process doesn't always do the trick with OSPF for some reason. Sometimes you have to restart the whole router.

NetworkVeteran

networker050184 wrote: »

Clearing the process doesn't always do the trick with OSPF for some reason. Sometimes you have to restart the whole router.

Yup. Since GNS3 runs the real IOS, like most quirks you find, you will also experience this on real equipment.

https://learningnetwork.cisco.com/thread/38796

d6bmg

networker050184 wrote: »

Clearing the process doesn't always do the trick with OSPF for some reason. Sometimes you have to restart the whole router.

Yes, that happens almost all the time in GNS3. One need to restart the router after saving to be able to see the changes.

Danielh22185

I've noticed I have had issues as well with this in GNS3. Sounds like there was a previous configuration that made the router use a different RID. OSPF should work fine though. Try the reload.

d6bmg

Danielh22185 wrote: »

I've noticed I have had issues as well with this in GNS3. Sounds like there was a previous configuration that made the router use a different RID. OSPF should work fine though. Try the reload.

Or trying out new images in GNS3 won't hurt either.

hitmen

In a real production network, what should I do?
I cant possibly restart a router!

NetworkVeteran

As per the thread I linked to, you'd have better chances with the OSPF "router-id" command made for this purpose.

I would add, even real production routers are actually restarted from time-to-time. I would question why there was this sudden need to change the router-id on an in-production device w/o waiting for the next planned maintenance.