nanog mailing list archives
Ciscos, BGP, L2TPV3 pseudowires and loopback IPs
From: James Smallacombe <up () 3 am>
Date: Wed, 10 Nov 2010 11:20:37 -0500 (EST)
A simpler question(s) than it sounds:Customer just brought up their first BGP session at a new location. It is up fine with a full routing table, the second provider hookup is a few weeks away.
The provider allocated a /24 (x.x.1.0/24) for the network and a /30 for the PTP connection (x.x.129.172/30). For the initial setup, I did not configure a loopback, I just put x.x.129.174 on the WAN interface and set up the neighbor as x.x.129.173. It's working fine.
We will need to set up a L2TPV3 tunnel to their old location (single homed, no BGP on that side). Upon initial reading of Cisco docs to do this, we will need a routable IP on a loopback interface for starters. Using one from the /24 LAN is out unless we subnet it, which we don't want to do.
So the question is, can I just "move" the PTP IP address x.x.129.174 from the WAN interface to the loopback like this?
interface Loopback0 ip address x.x.129.174 255.255.255.252 (that's the mask we're using on the WAN- Cisco's loopback examples show .255) interface WAN1 (actually a gigether) ip unnumbered loopback0 (or no ip addr?) neighbor x.x.128.173 update-source Loopback0Does this look even close to right? Or do we need another, single routabe IP from the provider for the loopback? Also, I am assuming we don't need separate loopback interfaces for BGP as for the Bridge/Tunnel. What about when the second provider comes up? A second or third loopback to nail up their WAN IP?
***OR*** is there a way to put their WAN I/F IP on the loopback and take it off their LAN Ether...and then do IP unnum loop0 on the LAN?
TIA, James Smallacombe PlantageNet, Inc. CEO and Janitor up () 3 am http://3.am =========================================================================
Current thread:
- Ciscos, BGP, L2TPV3 pseudowires and loopback IPs James Smallacombe (Nov 10)
- Re: Ciscos, BGP, L2TPV3 pseudowires and loopback IPs David Freedman (Nov 10)
- Re: Ciscos, BGP, L2TPV3 pseudowires and loopback IPs Dave Temkin (Nov 10)
- Re: Ciscos, BGP, L2TPV3 pseudowires and loopback IPs James Smallacombe (Nov 11)
- Re: Ciscos, BGP, L2TPV3 pseudowires and loopback IPs Jack Bates (Nov 11)
- Re: Ciscos, BGP, L2TPV3 pseudowires and loopback IPs Dave Temkin (Nov 10)
- RE: Ciscos, BGP, L2TPV3 pseudowires and loopback IPs Jeff Saxe (Nov 11)
- Re: Ciscos, BGP, L2TPV3 pseudowires and loopback IPs David Freedman (Nov 11)
- RE: Ciscos, BGP, L2TPV3 pseudowires and loopback IPs Ryan Finnesey (Nov 11)
- RE: Ciscos, BGP, L2TPV3 pseudowires and loopback IPs Seth (Nov 11)
- Re: Ciscos, BGP, L2TPV3 pseudowires and loopback IPs David Freedman (Nov 10)
- <Possible follow-ups>
- Re: Ciscos, BGP, L2TPV3 pseudowires and loopback Ips David Freedman (Nov 10)
- RE: Ciscos, BGP, L2TPV3 pseudowires and loopback Ips nanog (Nov 11)