I need some help with understanding this.

There is a network that i'm busy doing ip modifercations on. the modifercations are being done in preperations for something else down the line.

One of the things i have to do is change the ip the the OSPF is using. this is a small problem as changing the IP and then ID of the OSPF means a flush of the routes and rebuild. this creates a problem as the traffic needs to keep going, it cannot be stalled.

the thought came to me that maybe i should create a new ospf instance with the new ID then just move things over untill the old instance is no longer being used but i hit a snagged with the backbone area.
I have no idea how it will react if i create a new backbone area, with the same ID on the new instance. how will this area and the old area react, is means plausible, i do not know.

You can build more than one instance using the same router-id and have two backbones. You will however have to redistribute between the two instances if you need to exchange routes and that could get messy for you.

I would suggest using GNS3 and VirtualBox to lab this before putting it into production so you can evaluate potential issues and develop a plan.

Thanks

That a good idea. I'll try test it first

You could put in static routes to carry you over while you make your ospf changes.

the static routes pose a problem as the network is much of a spiders web.

after lots of testing i found a solution to the whole thing
its quite the mission but it keeps the network going

so first thing, this network was not setup all that well. ospf networks are set to 0.0.0.0/0
the first thing i needed to do was break down the ospf network into more component pieces by setting up the interlink networks first.
these routers are wireless towers so they have pppoe client connecting to them. i put them onto a nat but they are to be placed in a ospf area

after the default instance was done being prepped i began setting up the temporary system.
first, on ever interlink backbone i created a vlan. a set or temp /30's where put on these links.
next i created a new OSPF instance with an accompanying bridge and /32 for the ospf ID and set the temp /30's as its network and made sure the ospf was coming up on those.

it this point i'm able to do another quick change and that is added another set of vlans on the interlinks. i moved the existing ips from the host interface to the vlan.

now the preparations are done. i create a new bridge with the new IP for the ospf and change the ID to that. with that done the route list can flush itself and rebuild without affecting the flow of the traffic.


ps. Am i able to change the name of this thread so that it reflects the conversation better