Sounds like you are using BGP Signaled MPLS VPN over mGRE which uses a Route-Map on the neighbor relationship to provide the tunnel information. http://www.cisco.com/en/US/docs/ios-xml/ios/interface/configuration/xe-3s/ir -mpls-vpnomgre-xe.html
David -- http://dcp.dcptech.com > -----Original Message----- > From: cisco-nsp-boun...@puck.nether.net [mailto:cisco-nsp- > boun...@puck.nether.net] On Behalf Of John Neiberger > Sent: Wednesday, January 30, 2013 10:55 AM > To: Adam Vitkovsky > Cc: cisco-nsp@puck.nether.net > Subject: Re: [c-nsp] MPLS VPN over mGRE > > The type of MPLS VPN over mGRE that we're using doesn't use a > preconfigured > tunnel interface or NHRP. As I understand it, the peers share > tunnel-related information in vpnv4 updates using a SAFI of 64. This tells > the other peers that those prefixes are related to the mgre tunnel and that > signals the receiving router to set up an adjacency over the multipoint > tunnel, but I'm not quite sure how it does this. I don't understand what > element of the config tells the router to use SAFI 64 in the vpnv4 updates > instead of just treating them like regular L3VPN vpnv4 updates. It's kind > of confusing. There seems to be a lot of magic happening under the hood > here that I'm missing. > > John > > > On Wed, Jan 30, 2013 at 1:15 AM, Adam Vitkovsky > <adam.vitkov...@swan.sk>wrote: > > > Wow they really shrunk it down to three commands plus the route-map, > now > > that's something. > > > > > or is there some other mechanism that triggers tunnel endpoint > discovery? > > I believe since it's called mGRE it has to be NHRP taking care of > > everything > > in the background. > > Does the loopback IP has to be allocated from a common range that has to > be > > shared among the PEs? > > > > I thought it's done via standard mGRE tunnels: > > > > interface Tunnel0 > > ip address 192.168.1.1 255.255.255.0 > > ip mtu 1440 > > ip nhrp authentication cisco123 > > ip nhrp map multicast dynamic > > ip nhrp network-id 1 > > tunnel source FastEthernet0/0 > > tunnel mode gre multipoint > > tunnel key 0 > > ip router isis 1 > > > > -maybe "mpls ip" cmd. wouldn't work with mGRE Tunnel Int. > > > > > > adam > > > > > _______________________________________________ > cisco-nsp mailing list cisco-nsp@puck.nether.net > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/