[163096] in North American Network Operators' Group
Re: ISIS and OSPF together
daemon@ATHENA.MIT.EDU (vijay gill)
Sun May 19 13:37:44 2013
In-Reply-To: <m2a9o04luj.wl%randy@psg.com>
Date: Sun, 19 May 2013 10:35:12 -0700
From: vijay gill <vgill@vijaygill.com>
To: Randy Bush <randy@psg.com>
Cc: "nanog@nanog.org" <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Randy is correct. In most cases, the two protocols are running co-incident
for a while so you can do your table validation and topology mapping and
then you turn off OSPF. For vendors that aren't capable of supporting ISIS,
this is a feature and not a bug.
On Sun, May 12, 2013 at 1:57 AM, Randy Bush <randy@psg.com> wrote:
> > One scenario that i can think of when somebody might run the 2 protocols
> > ISIS and OSPF together for a brief period is when the admin is migrating
> > from one IGP to the other. This, i understand never happens in steady
> > state. The only time this can happen is if an AS gets merged into another
> > AS (due to mergers and acquisitions) and the two ASes happen to run ISIS
> > and OSPF respectively. In such instances, there is a brief period when
> two
> > protocols might run together before one gets turned off and there is only
> > one left.
>
> no. some ops come to see the light and move their network from ospf to
> is-is. see vijay gill's nanog preso
> http://nanog.org/meetings/nanog29/presentations/aol-backbone.ram
>
>
