discontiguous ospf areas with the same name

[n.titchener]

Hi all,

we are about split an area within our ospf network. So the question is can these two areas, which will be discontiguous, have the same area number? I know a quick answer might be to just change the area names but this will be a lot of work and if it goes wrong there will be financial implications so it will only be done if absolutely necessary.

[Harold Ritter]

Although a discontiguous backbone area will definitely cause issues, there is nothing wrong with having a discontiguous non-backbone area.

Here's a quote from RFC2328 section 3.7:

OSPF does not actively attempt to repair area partitions. When an area becomes partitioned, each component simply becomes a separate area. The backbone then performs routing between the new areas. Some destinations reachable via intra-area routing before the partition will now require inter-area routing.

Hope this helps,

[n.titchener]

Thanks for the reply. WE will find out if there are any issues I'm sure but it won't be until later in September. If this question is still floating around when the change takes place i'll update this string.

Once again cheers

[jtantsura]

ospf area numbers are locally (to the area) significant