[c-nsp] Deny Default Route Propagation

[Tony]

Ivan is correct, I know this first hand after wrestling with this very recently.

You can only filter inbound from OSPF to the route table and you will need to do it on each OSPF router in the area.

Cisco reference is here:
http://www.cisco.com/en/US/tech/tk365/technologies_q_and_a_item09186a0080094704.shtml#q12
http://tinyurl.com/m4kvgg


regards,
Tony.

--- On Fri, 7/8/09, Ivan Pepelnjak <ip at ioshints.info> wrote:

> From: Ivan Pepelnjak <ip at ioshints.info>
> Subject: Re: [c-nsp] Deny Default Route Propagation
> To: "'Jeremiah Best'" <jbest at zyedge.com>, skoal at skoal.name, "'Manaf Al Oqlah'" <manafo at hotmail.com>
> Cc: cisco-nsp at puck.nether.net
> Date: Friday, 7 August, 2009, 3:40 AM
> No, you cannot control the LSA
> flooding (apart from blocking the flooding
> over a particular interface). All LSAs still get to all the
> routers (this is
> what you've asked for: OSPF is a link-state protocol :),
> but you can control
> which of the best OSPF routes get inserted in the IP
> routing table with the
> "distribute-list in".
> 
> Ivan
>  
> http://www.ioshints.info/about
> http://blog.ioshints.info/
> 
> > -----Original Message-----
> > From: Jeremiah Best [mailto:jbest at zyedge.com]
> 
> > Sent: Thursday, August 06, 2009 6:13 PM
> > To: Ivan Pepelnjak; skoal at skoal.name;
> 'Manaf Al Oqlah'
> > Cc: cisco-nsp at puck.nether.net
> > Subject: RE: [c-nsp] Deny Default Route Propagation
> > 
> > Can't you do a "distribute-list out" on the ABR/ASBR 
> > whichever the router is?
> > 
> > -----Original Message-----
> > From: cisco-nsp-bounces at puck.nether.net
> 
> > [mailto:cisco-nsp-bounces at puck.nether.net]
> On Behalf Of Ivan Pepelnjak
> > Sent: Thursday, August 06, 2009 12:01 PM
> > To: skoal at skoal.name;
> 'Manaf Al Oqlah'
> > Cc: cisco-nsp at puck.nether.net
> > Subject: Re: [c-nsp] Deny Default Route Propagation
> > 
> > Just make sure you configure the "distribute-list in"
> on ALL 
> > OTHER routers in the area, otherwise you'll get some 
> > hard-to-troubleshoot loops or blackholes.
> > 
> > Ivan
> >  
> > http://www.ioshints..info/about
> > http://blog.ioshints.info/
> > 
> > > -----Original Message-----
> > > From: Gergely Antal [mailto:skoal at skoal.name]
> > > Sent: Thursday, August 06, 2009 2:24 PM
> > > To: Manaf Al Oqlah
> > > Cc: cisco-nsp at puck.nether.net
> > > Subject: Re: [c-nsp] Deny Default Route
> Propagation
> > > 
> > > http://www.cisco.com/en/US/docs/ios/12_0s/feature/guide/routmap.html
> > > 
> > > Manaf Al Oqlah wrote:
> > > > hello,
> > > > 
> > > > In OSPF, how can I filter the default route
> from being
> > > propagated out in the same area? I want to deny
> the 
> > external default 
> > > route in outbound routes so other routers in the
> same area doesn't 
> > > accept the default route from that router.
> > > > 
> > > > Thank you,
> > > > Manaf
> > > >