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OSPF stuck in Init State

Posted: Fri Jun 14, 2013 1:16 am
by ScottReed
We have been having some headaches with OSPF in our "backbone" area.

About a year ago we started to route our network and began by installing an RB1200 at our largest tower site. Our "core" router is also an RB1200 and resides at our fiber handoff location. We built a dedicated wireless link between the routers and started OSPF. No issues. Both these routers were and still are in the "backbone" area.

Router A is at our fiber handoff
Router B is at our largest tower site

Over the past year we have installed more routers and began to implement multiple areas. All of these new areas are built off of Router B. We have redundancy and never had any issues.

About a month ago we decided to replace the original link from Router A to Router B. We dedicated new IP's and new ports on each router and plugged the links in. I proceeded to disable the network for the original link in /routing ospf network at both Router A and Router B. I then added the new network at both routers. I watched as the original OSPF Interface disappeared from /routing ospf interface and the new interface showed up. This happened on both routers.

Router A shows that the OSPF Interface has one neighbor (router B) but is in Init state with no adjacent neighbors.

Router B shows that the OSPF Interface has zero neighbors.

I cannot get OSPF running. I am forced to still run on our old link to keep things working.

Any ideas?

Scott Reed

Re: OSPF stuck in Init State

Posted: Fri Jun 14, 2013 1:53 am
by ScottReed
Just found this:

I changed the OSPF interface from Broadcast to NBMA. Appears to be working now...

I have absolutely no clue why this would solve my issue, as I have used broadcast on all my links and run OSPF without issue.

The PTP link consists of two Rocket M5's, multicast enabled in Advanced. Latest firmware. 5.5.6

I'm not 100% convinced yet, but once I am, I will reply back and mark as solved.

Re: OSPF stuck in Init State

Posted: Tue Feb 24, 2015 12:44 am
by ropix
Thats happen in my router now, I am using RB2011 with ROS V6.27, link using radio ubiquity with newest firmware.
I have no Idea, event i change it to ptmp network type, ospf still showing "init" status in one router and no detect in neighbors in another router.

Re: OSPF stuck in Init State

Posted: Thu Feb 26, 2015 7:43 am
by ZeroByte
Make sure both ends are using WDS as well. That's caused strange layer3 hauntings before for me.
Setting NBMA and statically defining the neighbors' addresses causes OSPF to switch to unicast transmission, by the way.
(I think it's nbma, anyway)

Re: OSPF stuck in Init State

Posted: Thu Feb 26, 2015 3:21 pm
by ScottReed
I have struggled with OSPF across wireless links in my network for some time now. As stated in my original posts, I switched from BROADCAST to NBMA and it helped at the time. But, as I've upgraded RouterOS and upgraded AirOS, I've since reverted back to BROADCAST.

The bottomline here is that the OSPF implementation on the RouterOS platform is not the problem. The problem is in the links between the routers and the broadcasts are not traversing the link. All it takes is a link to drop below 90% CCQ, even for a moment, and the OSPF will drop.

For the most part my OSPF problems are gone. When we do have an OSPF issue in almost all cases the link is running poorly or is fluctuating CCQ.

Furthermore, I have found that using OSPF in situations where you don't have enough links to build redundancy just isn't practical. I use RIP when I have a site that is at the end of a spoke on the topology. It's pointless to run OSPF in these situations because if the link fails the site is going down regardless. To clarify, I am only using OSPF where I can benefit from it.

My recommendation to you is to make sure your UBNT links are running in WDS Bridge mode (as stated by the other poster), Multicast and Multicast Enhancement are enabled and your links are solid. High 90's CCQ, good AC/AQ and minimal TX/RX fluctuation.

Once you have that, just run OSPF in broadcast mode.

Re: OSPF stuck in Init State

Posted: Thu Feb 26, 2015 9:27 pm
by ZeroByte
Yes - I had the same problem where errors on link causing packet loss result in OSPF flaps. (Hellos being dropped, for instance.)

Even if you have redundant links, OSPF flaps could cause strange issue or unnecessary overhead due to frequent topology changes. Another option you could try is decreasing the hello interval and increasing the dead time. Basically it would have to miss several hellos in a row to drop, but would be slower to converge around real outages.

If you play with timers, remember that you have to do the same for all neighbors on a network segment or else they will have trouble forming and keeping adjacencies.