ISIS and OSPF together

Sun May 12 08:57:08 UTC 2013

> 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