Re: IOS XR ebgp question

Hi,

Only if you need to have end-to-end LSP between Multile BGP AS

http://www.cisco.com/c/en/us/td/docs/ios_xr_sw/iosxr_r3-7/mpls/configuration/
guide/gc37v3.html#wp1169308

Configuring a Static Route to a Peer

Perform this task to configure a static route to an Inter-AS or CSC-CE
peer.

When you configure an Inter-AS or CSC peer, BGP allocates a label for a /32
route to that peer and performs a NULL label rewrite. When forwarding a
labeled packet to the peer, the router removes the top label from the label
stack; however, in such an instance, BGP expects a /32 route to the peer.
This task ensures that there is, in fact, a /32 route to the peer.

Please be aware of the following facts before performing this task:

b"A /32 route is not required to establish BGP peering. A route using a
shorter prefix length will also work.

b"A shorter prefix length route is not associated with the allocated label;
even though the BGP session comes up between the peers, without the static
route, forwarding will not work.

On Mon, Feb 16, 2015 at 5:58 AM, Tony Singh <mothafungla_at_gmail.com> wrote:

> No, it's only for VPNv4 or VPNv6 and where we need CEF to bind MPLS labels
> across the Inter AS link, this does not happen automatically in XR as it
> does in IOS.
>
> What happened when you tested it?
>
> --
> BR
>
> Tony
>
> Sent from my iPad
>
> > On 16 Feb 2015, at 00:09, Tauseef Khan <tasneemjan_at_googlemail.com>
> wrote:
> >
> > Hi All,
> > When configuring the ebgp peer (ipv4 unicast) on XR is there a need to
> have
> > a /32 host route for the peer pointing to outgoing interface towards the
> > peer.
> > e.g
> > two ebgp peers ips are:
> > R1: 10.50.0.1/24 AS1 pos0/7/0/0
> > r2: 10.50.0.2/24 AS2 pos0/7/0/0
> >
> > on R1:
> > router bgp 1
> > address-family ipv4 unicast
> > network x.x.x.x
> > !
> > neighbor 10.50.0.2
> > remote-as 2
> > address-fmaily ipv4 unicast
> > route-policy X in
> > route-policy X out
> >
> >
> > router static !! < - Is there any need for the static route?
> > address-family ipv4 unicast
> > 10.50.0.2/32 pos0/7/0/0
> >
> > Kind regards
> >
> >
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Received on Mon Feb 16 2015 - 10:57:46 ART