From: Tom Larus (tlarus@xxxxxxxxxxxxxxx)
Date: Sat Jun 08 2002 - 22:21:18 GMT-3
I'd like to ask about the downside of another approach that seems too good
to be true. In doing practice labs, I like to tag routes from other
protocols as they are redistributed into OSPF (for example, tag routes from
IGRP 120 with tag 120), then have a route-map that stops those routes from
going back into the other protocol. The problem is that one does not see
this in case studies or in practice lab solutions very often, and that makes
me nervous. Doyle I contains a reference to this use of tags in the chapter
on route-maps, and that makes me feel a little better.
This has the feel of something that seems neat but is very dangerous.
Basically, anything that does involve manually typing in half the routes in
my network feels wrong, because it is not the tedious method that involves
as much typing of routes as possible and nailing things down manually.
--- Original Message -----
From: "Anthony Pace" <anthonypace@fastmail.fm>
To: "Tom Larus" <tlarus@novacoxmail.com>; "Dennis Laganiere"
<dennisl@advancedbionics.com>; "'Paul Connelly'" <chewy7700@yahoo.com>;
<ccielab@groupstudy.com>
Sent: Saturday, June 08, 2002 8:01 PM
Subject: OSPF into IGRP and summarizing into FLSM
> Tom Larus said "Let's say you have loopback addresses on OSPF enabled
> routers that you will need to summarize so that an IGRP /24 network
> will be able to see them and reach them. You redistribute them into
> OSPF, and use summary-address ip mask to summarize them right there on
> the same router, which is by definition an ASBR because redistribution
> is happening on it. Works like a charm."
>
> In other words you are using IP SUMMARY under OSPF even though you want
> to shoot the /24 into IGRP? Then, a /24 is created right there on that
> router and puhed into the IGRP world? Is that correct?
>
> I have been looking at this list for a definitive answer on this for a
> while (not wanting to repost a question if it has allready been
> answered) This seems like a solution. The quesion has been asked many
> times and interpreted or missinterpreted differently in different posts
> but essentially this is the problem as I see it: All of the protocoles
> on the LABS we have all been doing have a mechanism for redistributing
> and controlling summarization except IGRP. The LABS almost always give
> you the ability to summarize almost all your networks via these other
> mechanisms long before they reach the OSPF/IGRP redistribution point
> with the exeption of a loopback or directly connected network on that
> router which does not conform to the IGRP FLSM. It has been suggested
> that a "ip default-network" be shot into IGRP and this works but it is
> questionable as to weather this constitutes an ILLEGAL STATIC ROUTE.
> The Solie labs pose this scenario but the soltions do not address it.
>
> Are there any other tools that can be used?
>
> Anthony Pace
>
>
>
> On Tue, 4 Jun 2002 13:35:53 -0400, "Tom Larus" <tlarus@novacoxmail.com>
> said:
> > I have never taken the lab, so I could not speak to that aspect of the
> > question, but I did learn something recently I thought was neat, but
> > that
> > many others here have probably known for years.
> >
> > Let's say you have loopback addresses on OSPF enabled routers that you
> > will
> > need to summarize so that an IGRP /24 network will be able to see them
> > and
> > reach them. You redistribute them into OSPF, and use summary-address
> > ip
> > mask to summarize them right there on the same router, which is by
> > definition an ASBR because redistribution is happening on it. Works
> > like a
> > charm.
> >
> > Okay, it's old hat for a lot of you old hands, but I still think it is
> > pretty neat.
> >
> >
> > ----- Original Message -----
> > From: "Dennis Laganiere" <dennisl@advancedbionics.com>
> > To: "'Paul Connelly'" <chewy7700@yahoo.com>; <ccielab@groupstudy.com>
> > Sent: Tuesday, June 04, 2002 12:40 PM
> > Subject: RE: Connected routes vs network statement
> >
> >
> > > Some routing protocols will interpret the two differently. EIGRP, or
> > > instance, will see the redistributed route as external, which has a
much
> > > higher AD.
> > >
> > > --- Dennis
> > >
> > >
> > > -----Original Message-----
> > > From: Paul Connelly [mailto:chewy7700@yahoo.com]
> > > Sent: Tuesday, June 04, 2002 9:03 AM
> > > To: ccielab@groupstudy.com
> > > Subject: Connected routes vs network statement
> > >
> > > Is there a preference in the lab when to use "redistribute connected"
vs.
> > > network statements? I know the redistribute connected will not turn on
the
> > > routing protocol on the interface but you can easily turn it off with
> > > passive-interface. Just want to check if the exam wants you to do it a
> > > certain way.
> > >
> > >
> > >
> > > Thanks
> > >
> > >
> > >
> > > ---------------------------------
> > > Do You Yahoo!?
> > > Sign-up for Video Highlights of 2002 FIFA World Cup
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