Path: utzoo!attcan!uunet!samsung!usc!ucsd!ucbvax!proteon.com!jmoy
From: jmoy@proteon.com (John Moy)
Newsgroups: comp.sys.proteon
Subject: Implementing OSPF areas in a Proteon router
Message-ID: <9011051350.AA17921@monk.proteon.com>
Date: 5 Nov 90 13:50:40 GMT
References: <780@malgudi.oar.net>
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 49

Kannan-

Here is an attempt to answer your P4200 OSPF questions:

Problem 1: (Selectively import only certain static routes).

	The P4200 won't let you do this. What the P4200 does do is
	to separate the IP routing information into three broad
	categories (RIP-derived, EGP-derived and static/direct
	routes). Each category can then be imported (or not imported)
	into OSPF. For example, you can choose to import RIP routes,
	but not	EGP or static routes.

	There are two places in the P4200's IP routing software where
	route filtering can be done on a per-network basis. The first
	is the EGP exchange tables (using this, you can set it up so
	that only certain EGP routes are imported into OSPF). The
	second is the "RIP-accept" filters, which define the set of
	routes that can be received by the P4200's RIP software
	(depending how your routing is set up, this may allow you
	to import only a subset of the RIP routes into OSPF). But
	neither of this features helps you much when importing
	static routes.

	In the P4200 implementation of OSPF version 2, we have
	separated the direct/static routes into two separate
	categories. So, you can now import directly attached routes,
	but not static routes. I don't know if this helps you
	any (and the version 2 code has not yet been released).

Problem 2: (why are all these subnets being imported?)

	In release 8.2, you can condense all your subnets into a single
	network-level only when all the subnets belong to a single OSPF
	area. In your case, all the subnets of 128.183.0.0 don't really
	belong to an OSPF area, but instead are external (RIP-derived or
	direct) routes. So, if you configure the P4200 to import
	RIP and static/direct routes, each subnet will be imported
	as a separate OSPF (type 5 LSA) external route.

	There is a solution for this in the (again, unreleased)
	P4200 OSPF version 2 code. In that software, you can set
	a switch saying that you do not want to import any subnets
	as external routes. If this switch is enabled in your
	configuration, only a single route will be imported (destination
	128.183.0.0, mask 255.255.0.0) for the entire subnetted
	network.

John