OSPF: Migrate other areas into area 0 (consolidation) or other alternative?

[RUDY SETIAWAN]

Hi all,

Currently, our network infrastructure has area 50 and area 0.  Area 50 has about 5 routers and Area 0 has about 3 routers.

3 of the 5 routers in Area 50 are ABRs and all of the area0 routers are ABRs to the Area50 routers.

The problem that I am having is that I am unable to prioritize which ABR should the packet goes in/out. I want to choose ABR-1 in Area50 to be the main link to Area0 ABR-1.

I am thinking of migrating area50 to area0 and maybe using the ospf cost to prioritize.

Or if there is a way where I can prioritize which ABR on the existing infrastructure?

Thank you

[Reza Sharifi]

Hi Rudy,

If area 50 is a simple area with no STUB or NSSA and you don't have a large OSPF database, then I would say for only 8 routers one area (area 0) is good enough.

HTH

Reza

[RUDY SETIAWAN]

Hi Reza, thanks for the advice.

Since this is in production, what happen if I change the network statement from area 50 to area 0? Will it disconnect the network?

Thanks,

Rudy

[Reza Sharifi]

Hi Rudy,

Yes, there is going to be an outage since you have to changed both sides, and the peeing will need to come up in the new area.

In below example I changed the area from 5 to 6 and as you can see the timer for the neighbor was reset.

I would defiantly do it during an outage window after hours.

T-1(config-router)#do sh ip os ne det
Neighbor 10.100.6.10, interface address 172.17.1.1
    In the area 5 via interface GigabitEthernet0/0
        Neighbor is up for 00:00:06
           
T-1#sh ip os  ne det
Neighbor 10.100.6.10, interface address 172.17.1.1
    In the area 6 via interface GigabitEthernet0/0       
    Neighbor is up for 00:00:07

HTH

Reza