Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

OSPF

I want to build test network and i need advice. Here my scenario:

-----R1-City C

e0 - Area 3 -stub or nssa?

s1.1 - Area 0 - Frame Relay to R2-s0/0.2

-----R4-City A

e0 - Area 5 -stub or nssa?

s1- Area 2- Frame Relay to R2-s0/0.1

-----R2-City B,Campus 1

s0/0.1- Area 2- Frame Relay to R4-s1

s0/0.2- Area 0- Frame Relay to R1-s1.1

e0/0- Area 1 - Ethernet to R3-e0

-----R3-City B,Campus 2

e0- Area 1- Ethernet to R2-e0/0

e1 - - Area 4 -stub or nssa?

----------

Is't right or maybe not? Which other advices?

Is't necessary virtual link from Area 4 and Area 5?

5 REPLIES

Re: OSPF

In this case you will need to configure a virtual link from R3 to R2, with area 1 as transit area to link area 4 to area 0.

You also need a virutal link from R4 to R2, with area 2 as transit area, to link area 5 to area 0.

HTH

New Member

Re: OSPF

If I am understanding your setup (and I am not sure I do), you will indeed need virtual links for A4 and A5. I am just uncertain as to why you would set it up this way. As far as stub vs. NSSA, depends what you are doing in Areas 3, 4 and 5. If you stick to your current design, then they can be stubs.

HTH

New Member

Re: OSPF

How about this suggestion,

Make the ethernet port of R2, e0/0 and both ethernet ports of R3 e0, e1 area0. Then all the ports of R1 and the interface connecting them on R2 (s0/0.2) area1. Finally all the interfaces on R4 and the interface connecting them on R2 (s0/0.1) in area2.

This gives two areas that both connect to area0, the choice of stub or NSSA is dependent on what is going on on the networks.

New Member

Re: OSPF

Yes, it's very interesting suggestion!

Can you little explain me in which situations i must break into two different areas( like i made before) and when i must unite routers in one area(like you offered)? Is't because reduce areas or avoid to create virtual links for connecting Area 0?

New Member

Re: OSPF

Sorry I did not respond earlier but I have been away for a few days.

I think the limit for an area is approx 25/30 routers, however I usually work on the basis of an area for each wan link from area0 as I think this makes the administration easier. However there is a cisco design guide here

http://www.cisco.com/en/US/tech/tk365/tk480/tech_design_guides_list.html

Hope this helps

Tom

142
Views
6
Helpful
5
Replies