[Xorp-users] 2 BGP Peers Simultaneously

[Mark Handley]

There are several possibilities, and it's hard to distinguish them
from the information so far.

 - The connection isn't getting properly established.  This seems
unlikely, given show bgp peers indicates it's up.
 - The 2002::2 peer isn't happy with the connection and isn't sending
you routes.
 - XORP is dropping routes from 2002::2 in the inbound filters for
some reason.  I can't see any obvious reason.
 - The 2002::2 peer prefers the routes from 2001::1 to its own routes.
 - There's a bug.   This seems unlikely given how simple the config is.

So, some questions:

1.  Does 2002::2 think the peering is reaching established state?
2.  Is 2002::2 receiving routes from 2001::1?  As the peering is EBGP,
it should be receiving routes that 2001::1 received from 2003::1 and
forwarded.  Now, if 2002::2 did receive all the routes from 2001::1
and preferred them to its own routes, then (depending on which BGP
implentation it is) it might not resend your routes back to you, or it
might send them back but you'd drop them due to the loop filter.

Cheers,
Mark

On Thu, Apr 3, 2008 at 10:20 AM, Che, Ting-Shuo T. <tsche at mitre.org> wrote:
>
>
>
> Hi Mark,
>
> Thanks a lot for getting back to me. Nothing particular with the policy
> statement, and it makes no difference. The XORP Linux PC (65503) is
> configured with IPv6 2000::1/64 and IPv4 192.168.2.3/24. One BGP peer
> (65504) has 2000::2/64 and 192.168.2.4/24. Another BGP peer (65505) has
> 2000::3/64 and 192.168.2.5/24. Had tried next-hop: 192.168.2.3, instead of
> 192.168.2.6, for both peer 2000::2 and 2000::3, but did not succeed either.
> Any other recommendation for the configuration?
>
> Ting Che
>
>  ________________________________
>  From: mark.j.handley at gmail.com 代理 Mark Handley
> Sent: 2008/4/2 [星期三] 上午 03:11
> To: Che, Ting-Shuo T.
> Cc: xorp-users
> Subject: Re: [Xorp-users] 2 BGP Peers Simultaneously
>
>
>
>
>
> Was there something you were trying to do with the policy statement?
> If you remove that, does it make any difference?
>
>  - Mark
>
> On Tue, Apr 1, 2008 at 7:50 PM, Che, Ting-Shuo T. <tsche at mitre.org> wrote:
> >
> >
> > Installed XORP on Linux PC, started "./xorp_rtrmgr -b ipv6bgp.boot"
> > (2000::1) and then connect to
> > test equipment representing 2 BGP peers (2000::2 and 2000::3) with a lot
> of
> > prefixes each.
> >
> > Both peers reached ESTABLISHED state in "show bgp peers detail" and
> started
> > route injection, but
> > only those prefixes from one peer (2000::3) shows up in "show bgp routes
> > ipv6" and  "show route
> > table ipv6 unicast ebgp terse".
> >
> > Did I made mistake in the following configuration file?
> >
> > Thank you very much for your help.
> >
> > Ting Che
> >
> > /*XORP Configuration File, v1.0*/
> > protocols {
> >     bgp {
> >         bgp-id: 192.168.2.3
> >         local-as: 65503
> >         enable-4byte-as-numbers: false
> >         peer 2000::2 {
> >             peer-port: 179
> >             local-port: 179
> >             local-ip: 2000::1
> >             as: 65504
> >             next-hop: 192.168.2.6
> >             next-hop6: 2000::1
> >             holdtime: 90
> >             delay-open-time: 0
> >             client: false
> >             confederation-member: false
> >             disable: false
> >             ipv4-unicast: false
> >             ipv4-multicast: false
> >             ipv6-unicast: true
> >             ipv6-multicast: false
> >         }
> >         peer 2000::3 {
> >             peer-port: 179
> >             local-port: 179
> >             local-ip: 2000::1
> >             as: 65505
> >             next-hop: 192.168.2.6
> >             next-hop6: 2000::1
> >             holdtime: 90
> >             delay-open-time: 0
> >             client: false
> >             confederation-member: false
> >             disable: false
> >             ipv4-unicast: false
> >             ipv4-multicast: false
> >             ipv6-unicast: true
> >             ipv6-multicast: false
> >         }
> >         export: "block"
> >     }
> > }
> > fea {
> >     unicast-forwarding6 {
> >         disable: false
> >     }
> > }
> > interfaces {
> >     restore-original-config-on-shutdown: false
> >     interface eth0 {
> >         description: ""
> >         disable: false
> >         discard: false
> >         unreachable: false
> >         management: false
> >         vif eth0 {
> >             disable: false
> >             address 192.168.2.3 {
> >                 prefix-length: 24
> >                 disable: false
> >             }
> >             address 2000::1 {
> >                 prefix-length: 64
> >                 disable: false
> >             }
> >             address fe80::20f:1fff:fea8:70e4 {
> >                 prefix-length: 64
> >                 disable: false
> >             }
> >         }
> >     }
> > }
> >
> > policy {
> >     policy-statement block {
> >         term bgp_65503 {
> >             from {
> >                 protocol: "bgp"
> >             }
> >             then {
> >                 accept
> >             }
> >          }
> >     }
> > }
> >
> > _______________________________________________
> >  Xorp-users mailing list
> >  Xorp-users at xorp.org
> >  http://mailman.ICSI.Berkeley.EDU/mailman/listinfo/xorp-users
> >
> >
>