http://www.networkingblog.in/ospf-multiple-prcoess-id-and-areas-2902 Cisco Netpro Blog Wed, 23 Jun 2010 06:07:14 +0000 hourly 1 http://wordpress.org/?v=3.0 http://www.networkingblog.in/ospf-multiple-prcoess-id-and-areas-2902/comment-page-1#comment-2029 Kumar Mon, 15 Mar 2010 13:38:06 +0000 http://www.networkingblog.in/?p=2902#comment-2029 At least insofar as the drawing you give is concerned, you do not have discontiguous area 0s. What you have is 3 autonomous systems each with their own area 0. In situations where your'e trying to merge companies that have their own OSPF setups, then it's possible that this would be a reasonable interim solution to a a potentially sticky problem. However, I do not believe that this is a good long-term design. Even if the organization as a whole were large enough to warrant multiple IGP ASes, I wouldn't personally redistribute them into each other directly. I would probably move to BGP as an inter-AS solution if it were deemed necessary to continue the current design in some fashion. That said, unless we're talking about an extremely large organization, OSPF is probably more than adequate for the whole of it so long as the implementation is well-designed. At least insofar as the drawing you give is concerned, you do not have discontiguous area 0s. What you have is 3 autonomous systems each with their own area 0.
In situations where your’e trying to merge companies that have their own OSPF setups, then it’s possible that this would be a reasonable interim solution to a a potentially sticky problem. However, I do not believe that this is a good long-term design. Even if the organization as a whole were large enough to warrant multiple IGP ASes, I wouldn’t personally redistribute them into each other directly. I would probably move to BGP as an inter-AS solution if it were deemed necessary to continue the current design in some fashion.
That said, unless we’re talking about an extremely large organization, OSPF is probably more than adequate for the whole of it so long as the implementation is well-designed.

]]> http://www.networkingblog.in/ospf-multiple-prcoess-id-and-areas-2902/comment-page-1#comment-2028 karan Mon, 15 Mar 2010 13:37:19 +0000 http://www.networkingblog.in/?p=2902#comment-2028 In OSPF, the process ID is not the same as in other routing protocols. It is the area number that decides. Two routers need not have the same process ID but in your situation I agree that you have a discontiguous area0. You will find more info about this in the OSPF design guide at the following URL: http://www.cisco.com/en/US/partner/tech/tk365/tk480/tsd_technology_support_sub-protocol_home.html In OSPF, the process ID is not the same as in other routing protocols. It is the area number that decides. Two routers need not have the same process ID but in your situation I agree that you have a discontiguous area0. You will find more info about this in the OSPF design guide at the following URL:
http://www.cisco.com/en/US/partner/tech/tk365/tk480/tsd_technology_support_sub-protocol_home.html

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