[j-nsp] Filtering OSPF routes

[Hannes Gredler]

in JUNOS you can do similar things by applying a export policy under
the forwarding table branch; note that although the policy language
provides you with many "from" match-conditions not all do make
sense in a policy which control route flow beteen the
kernel routing table and the PFE

/hannes

On Tue, Feb 18, 2003 at 09:07:28PM +0100, Lars Erik Gullerud wrote:
| Well no, IOS also allows you to configure a route-map to block OSPF
| routes from being added to the routing-table, matching on any OSPF
| attributes. This will not help the original poster, since LSAs are still
| flooded normally and its his M5 he wanted to block the routes on. With
| this IOS feature, routes are only filtered from the RIB on the local
| router, but I believe what he was looking for was a similar feature in
| JunOS, which would probably be preferable to filtering the LSAs on the
| remote (Cisco) side.
| 
| I've never tried this feature myself, but Cisco calls this "OSPF Route
| Map-based filtering" and it's available in 12.0S trains. I guess it
| would correspond to an import filter in JunOS, which you can not set for
| OSPF.
| 
| /leg
| 
| On Tue, 2003-02-18 at 18:31, Kent Yu wrote:
| > IOS only allows filtering type-3 at ABR, I think the original poster's
| > intend was to filter LSA within the same area.
| > 
| > The feature could be useful for enterprise networks, do not think it is
| > helpful for the SPs.
| > 
| > Thanks
| > --kent
| > ----- Original Message -----
| > From: "Wayne (juniper nsp)" <wg-jnpr-nsp at wgustavus.com>
| > To: "Ben Buxton" <B.Buxton at Planettechnologies.nl>; "Ajay Bhardwaj"
| > <ajay.bhardwaj at in.spectranet.com>; <juniper-nsp at puck.nether.net>
| > Sent: Saturday, February 15, 2003 11:42 PM
| > Subject: Re: [j-nsp] Filtering OSPF routes
| > 
| > 
| > MessageActually, if you are running a sufficiently high enough version of
| > IOS (e.g. 12.0S), the 7200 can filter some LSAs.  It depends on your exact
| > scenario if this will accomplish what you are trying to do.  It does tend to
| > go contrary to the design of OSPF (or any link state protocol), but I
| > suppose enough people wanted the knob, so they got it.
| > 
| > Not sure if JUNOS has a similar knob.
| > 
| > - Wayne
| >   ----- Original Message -----
| >   From: Ben Buxton
| >   To: Ajay Bhardwaj ; juniper-nsp at puck.nether.net
| >   Sent: Monday, February 10, 2003 4:18 AM
| >   Subject: RE: [j-nsp] Filtering OSPF routes
| > 
| > 
| > 
| >   You cannot filter OSPF. This would break the requirement that all routers
| > have
| >   the same link state view.
| >   This is true for both Junos and IOS.
| > 
| >   BB
| >     -----Original Message-----
| >     From: Ajay Bhardwaj [mailto:ajay.bhardwaj at in.spectranet.com]
| >     Sent: Monday, 10 February 2003 08:39
| >     To: juniper-nsp at puck.nether.net
| >     Subject: [j-nsp] Filtering OSPF routes
| > 
| > 
| >     Hi all,
| > 
| >     We have cisco 7200 router and M-5 router both running ospf and part of
| > area 10.
| > 
| >     I want to deny few routes which are flowing trough ospf from 7200 to m5
| > either at 7200 side or m5 side. Pls if anyone have any solution to this
| > would be gr8 help for me.
| > 
| >     Ajay Bhardwaj