Hi,

I'd like to setup a test environment to test OSPF.

I have added a new instance and wanted to edit the "backbone" area to use my newly created instance.
But when I do so, by "/routing ospf area set instance=ospf1 backbone" I get the error "failure: can not change backbone area id".

Well that is fine for me, but I didn't want to change the area-id at all, I want to change the instance.

Am I missing something? How can I edit the instance of the default area?
Thank you!

--bpahlke

You can edit instance with decimal values. And you can set area name with letters and area-id with decimal values in IP address form

Example:

routing ospf instance set 0 router-id=3.3.3.3
routing ospf network add network=10.0.0.4/30 area=backbone
routing ospf network add network=10.0.0.8/30 area=backbone
routing ospf area add name=area2 area-id=0.0.0.2
routing ospf network add network=192.168.2.0/24 area=area2

Backbone area has a default 0.0.0.0 value of area-id. Others can be named with random letters as a names and ip address like form with decimal values as area-id's.

This is a typical configuration of ABR OSPF router.

Thank you for your answer Anumrak.

I do know that I can edit the default instance and area, but I wanted to create a new instance and use it in the backbone area.
I just hoped that there was a way to achieve that, with out using the default instance.

--bpahlke

You wanted to have 2 instances running in the same area? Or you wanted the same area id used for different instances?

Basically, the named area "backbone" is more like an alias, the cli does not check to ensure that there is instance separation for the alias. You can use area 0 (0.0.0.0) and call it something else like backbone1, but the name backbone isn't the area, it is just an alias, and it can not be duplicated.

The following is allowed:
That would create 2 instances both with area 0.0.0.0 (referred to as backbone) but with separate alias'

You wanted to have 2 instances running in the same area? Or you wanted the same area id used for different instances?

Basically, the named area "backbone" is more like an alias, the cli does not check to ensure that there is instance separation for the alias. You can use area 0 (0.0.0.0) and call it something else like backbone1, but the name backbone isn't the area, it is just an alias, and it can not be duplicated.

The following is allowed:

Code: Select all

/routing ospf instance add name=lab
/rouing ospf area add instance=lab name=backbone-lab area-id=0.0.0.0

That would create 2 instances both with area 0.0.0.0 (referred to as backbone) but with separate alias'

He won't have neighbors with different ospf instances.

You wanted to have 2 instances running in the same area? Or you wanted the same area id used for different instances?

Basically, the named area "backbone" is more like an alias, the cli does not check to ensure that there is instance separation for the alias. You can use area 0 (0.0.0.0) and call it something else like backbone1, but the name backbone isn't the area, it is just an alias, and it can not be duplicated.

The following is allowed:

Code: Select all

/routing ospf instance add name=lab
/rouing ospf area add instance=lab name=backbone-lab area-id=0.0.0.0

That would create 2 instances both with area 0.0.0.0 (referred to as backbone) but with separate alias'

Ah, thank you for the tip!

I've never bothered to create a second area with an ID 0.0.0.0.
I always assumed that this would be prohibited by the RouterOS.

It just is a habit of mine, I never like to use default entries.