Guys, check out the following session on Cisco Live 365: BRKRST-2045 (San Diego 2012 and/or London 2013)
Sent from my iPad On 31/01/2013, at 19:06, 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<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/ _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
