I have copied the log messages below.

OSPFv2 neighbor 10.10.3.1: state change from Exchange to 2-Way
Database Description packet has init bit set in middle of an exchange

I get those 2 lines over and over and I lose all my routes.

The logs also shows the following line a few times.

OSPFv2 neighbor 10.10.3.1: state change from ExStart to 2-Way



Can somebody tell me what is going on.

My routers are running ROS 5.4 and 5.5

Please let me know if you need more info.

Thanks

Upgrade. Both sides. That's a bug.

If it ain't fixed in 5.7 (current), email support@mikrotik.com.

Thanks, I'll do that tonight.

I'm not sure how this post ended up in the hardware forum.

I increased my MTU from default 1500 to 1512 between the two interfaces and those problems seem to have gone away,no more losing routes and no more errors in log file.Give it a bash and see if it works for you.

Had the same problem after upgrading routers from 4.10 to 5.24.

Thank you tyronzn for the temporary fix.