I asked Craig Hill about the feature pointing him to your support forum post. He said there is no special signaling. The route map does all the work.
David -- I'm currently all thumbs so I apologize for the short message. On Jan 31, 2013, at 3:07 AM, "John Neiberger" <[email protected]> wrote: > I bet you're right. I should keep digging for some Cisco Live presentation or > something. I was hoping someone from Cisco would respond and explain the > magic fairy dust in this configuration. As you said, it must be that the > inbound route-map also causes the neighbors to use SAFI 64 in outbound > updates. The docs I've seen so far don't say how it happens, they just said, > "And in this step, magic happens" or something similar. :) > > John > > > On Thu, Jan 31, 2013 at 1:02 AM, Adam Vitkovsky <[email protected]> > wrote: >> Aah I see, so it’s got to be the route-map than, mapping the particular >> neighbor with a profile –causing the neighbors to negotiate safi 64 support. >> >> You could try issuing “sh ip b vpnv4 a nei x.x.x.x” to see whether safi 64 >> has indeed been negotiated between the peers. >> >> >> >> I bet the insides are explained in some cisco presentation. >> >> >> >> adam >> >> >> >> From: John Neiberger [mailto:[email protected]] >> Sent: Wednesday, January 30, 2013 6:16 PM >> To: David Prall >> Cc: Adam Vitkovsky; [email protected] >> >> >> Subject: Re: [c-nsp] MPLS VPN over mGRE >> >> >> That's exactly right. The part I can't figure out is what triggers the >> proper signalling. The BGP config for outbound vpnv4 updates looks like >> standard L3VPN. I'm trying to understand what causes it to send the tunnel >> information in the NLRI. I believe it is using SAFI 64. What causes it to >> use SAFI 64 instead of 128, which is what would normally be used for MPLS >> VPNs? >> >> >> >> That's the part that's baking my noodle. I'm just not sure how it's working >> under the hood. >> >> >> >> John >> >> >> >> On Wed, Jan 30, 2013 at 9:15 AM, David Prall <[email protected]> wrote: >> >> 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: [email protected] [mailto:cisco-nsp- >> > [email protected]] On Behalf Of John Neiberger >> > Sent: Wednesday, January 30, 2013 10:55 AM >> > To: Adam Vitkovsky >> > Cc: [email protected] >> > 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 >> > <[email protected]>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 [email protected] >> > https://puck.nether.net/mailman/listinfo/cisco-nsp >> > archive at http://puck.nether.net/pipermail/cisco-nsp/ >> > _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
