[Xorp-users] Xorp, pimsm and ethertap

Mike Horn mhorn@vyatta.com
Fri, 24 Feb 2006 14:01:39 -0800 (PST)


Hi Calum,

It might look a bit strange, but yes your "local-ip" and "next-hop" need to be the same address for this configuration to work.  The only reference to the remote IP address is "peer <IP>".

Can you send the output from "show bgp peers detail", the "show bgp peers" command just shows you what is configured, not whether the session is actually established.  Look for the "Peer State:" line.

When you ask "How does xorp handle an interface disappearing, and coming back, out of interest?", do you mean the link state is changing, or that the interface itself is being deleted and re-added?


-mike

----- Original Message -----
From: Calum <caluml@gmail.com>
To: Mike Horn <mhorn@vyatta.com>
Cc: xorp-users@xorp.org
Sent: Friday, February 24, 2006 2:52:49 PM GMT-0700
Subject: Re: [Xorp-users] Xorp, pimsm and ethertap

Hello Mike,

I'm not sure about changing next-hop.
That leaves my config looking like:
protocols {
        bgp {
            bgp-id: 10.0.0.122  <-------- this is the local IP, right?
            local-as: 4
            peer "10.0.0.121" { <-------- This is the remote IP?
                as: 1
                peer-port: 179
                local-port: 179
                holdtime: 90
                delay-open-time: 0
                client: false
                confederation-member: false
                disable: false
                ipv4-unicast: true
                ipv4-multicast: false
                ipv6-unicast: false
                ipv6-multicast: false
                next-hop: 10.0.0.122 <----- This should be the remote IP?
                local-ip: "10.0.0.122" <------ This is the local IP ?
            }
        }

which looks odd with the same next-hop and local-ip. To me, anyway.

My current setup is

local = 10.0.0.122 (running xorp)
----tapinterface----
remote = 10.0.0.121 (running quagga bgpd)

I have an established BGP session up as shown on 10.0.0.121
quagga: # sh ip bgp neighbors 10.0.0.122
BGP neighbor is 10.0.0.122, remote AS 4, local AS 1, external link
  BGP version 4, remote router ID 10.0.0.122
  BGP state = Established, up for 00:00:48
Showing the advertised routes on that hosts shows the routes.
xorp# show bgp routes on the xorp box shows them all received.
They're just not making it into the kernel on 10.0.0.122

xorp-box > show bgp peers
Peer 1: local 10.0.0.122/179 remote 10.0.0.121/179


xorp-box # ifconfig taphush
taphush   Link encap:Ethernet  HWaddr CE:BC:C7:A6:C4:ED
          inet addr:10.0.0.122  Bcast:10.0.0.123  Mask:255.255.255.252


How does xorp handle an interface disappearing, and coming back, out
of interest?