Can one temporarily mix and match 3.14's OSPF and 2.9.51's OSPF or must the upgrade be done all at once?

Kind regards/ldv

It is not recommended to mix 2.9 and 3.14. Sometimes it is working but in most cases OSPF will fail to distribute routes correctly.

I'm successfully using 2.9.51 OSPF and 3.13 OSPF without any problems - there is 4 routeros 2.9.x routerboards and 8 routeros 3.1x routerboards and routes are distributing correctly with no problems

Hey,

For us it works almost well, we have about 15 rb's with 2.9.51 and about 10 rb's with 3.14. It works without problems as long as we don't change enything in ospf configuration, after that reboot is needed to get back network to usable state ;)

Regards,
KT.

I'm successfully using 2.9.51 OSPF and 3.13 OSPF without any problems - there is 4 routeros 2.9.x routerboards and 8 routeros 3.1x routerboards and routes are distributing correctly with no problems

Sorry my mistake 3.x OSPF is not compatible with 2.9 only if NBMA is used. Otherwise it should work.