Jo, I don't know that there is a normal one! As far as ease of configuration B2B VRF is the easiest, everything else is some form of External MP-BGP (with options for send-label, multi-hop, next-hop-self).
On Wed, Sep 9, 2009 at 9:07 AM, Jo Knight <[email protected]> wrote: > Thanks Bryan, > > I dont have that book, but think I just found my next purchase. > > What one is the 'normal' one - I know this has no bearing for the CCIE lab, > so its best to know all of the options. > > Jo > > 2009/9/9 Bryan Bartik <[email protected]> > > Jo, >> >> This is what I found as well. Basically there are multiple scenarios for >> option B, also know as option 2. In the book "MPLS Configuration on IOS >> Software" this particular scenario is described as "Option 2a: ASBR-ASBR >> Approach Using Next-Hop-Self Method" on page 288. >> >> >> On Wed, Sep 9, 2009 at 3:41 AM, Francisco <[email protected]>wrote: >> >>> I think what is saving the day is that you have the ‘next-hop-self’ for >>> the iBGP sessions. As you’ve already got MPLS Between the ASBR and PE’s, >>> the FEC/FIB should be properly tagged. >>> >>> >>> >>> If you didn’t include next-hop-self, then you’ll need send-label between >>> the ASBRs so the PE’s could do the tagging for the end to end LSP. >>> >>> >>> >>> Play around with those configs and compare the results for both sets >>> with: >>> >>> >>> >>> show ip bgp vpn all labels >>> >>> show mpls forwarding >>> >>> show ip bgp labels >>> >>> >>> >>> BTW: Anybody doing the exam on RTP on the 30th Sep? >>> >>> >>> >>> All the best, >>> >>> Francisco >>> >>> http://www.linkedin.com/in/fbaena >>> >>> >>> >>> >>> >>> >>> >>> *From:* Jo Knight [mailto:[email protected]] >>> *Sent:* 09 September 2009 09:45 >>> *To:* Bryan Bartik >>> *Cc:* Francisco; [email protected]; [email protected] >>> *Subject:* Re: [OSL | CCIE_SP] Inter-AS VPN Option B and send-label >>> >>> >>> >>> Hi Guys, >>> >>> Im just working though an Option B lab and have VPNv4 configured between >>> ASBRs. I do not have an IPv4 session between the ASBRs and it is working >>> fine and I am getting the labels on the PE routers (R3 and R6), nor do I >>> have mpls enabled between them. >>> >>> If we need to send-label between ASBRs does that mean we need to activate >>> IPv4 between them? >>> >>> R2 and R4 are the two ASBRs in AS1 and AS2 respectively: >>> >>> R2 ASBR BGP Config >>> router bgp 1 >>> no bgp default ipv4-unicast >>> no bgp default route-target filter >>> bgp log-neighbor-changes >>> neighbor 150.50.24.4 remote-as 2 >>> neighbor 200.0.0.3 remote-as 1 >>> neighbor 200.0.0.3 update-source Loopback0 >>> ! >>> address-family vpnv4 >>> neighbor 150.50.24.4 activate >>> neighbor 150.50.24.4 send-community extended >>> neighbor 200.0.0.3 activate >>> neighbor 200.0.0.3 next-hop-self >>> neighbor 200.0.0.3 send-community extended >>> exit-address-family >>> >>> >>> >>> R4 ASBR BGP Config >>> router bgp 2 >>> no bgp default ipv4-unicast >>> no bgp default route-target filter >>> bgp log-neighbor-changes >>> neighbor 150.50.24.2 remote-as 1 >>> neighbor 200.0.0.6 remote-as 2 >>> neighbor 200.0.0.6 update-source Loopback0 >>> ! >>> address-family vpnv4 >>> neighbor 150.50.24.2 activate >>> neighbor 150.50.24.2 send-community extended >>> neighbor 200.0.0.6 activate >>> neighbor 200.0.0.6 send-community extended >>> neighbor 200.0.0.6 next-hop-self >>> exit-address-family >>> ! >>> >>> >>> Thanks, >>> Jo >>> >>> 2009/8/7 Bryan Bartik <[email protected]> >>> >>> Thanks guys. I didn't have LDP enabled between the ASes. I just reviewed >>> the configuration guide for Inter-as mpls vpn with vpnv4 exchange between >>> asbrs and they don't use it either. >>> >>> >>> http://www.cisco.com/en/US/docs/ios/mpls/configuration/guide/mp_vpn_connect_asbr_ps6350_TSD_Products_Configuration_Guide_Chapter.html >>> >>> On Fri, Aug 7, 2009 at 3:52 AM, Francisco <[email protected]> >>> wrote: >>> >>> Did you check if you had 'mpls ip' enabled on the interface connecting to >>> the eBGP neighbour? >>> >>> As you know there are 3 ways for MPLS to exchange labels: >>> >>> - LDP >>> - BGP >>> - RSVP-TE >>> >>> If you've been enabling mpls on the interfaces connecting eBGP >>> neighbours, >>> then they've changed labels anyway and the send-label command is >>> redundant. >>> >>> I had the same situation with a mock lab in the INE bootcamp. I had >>> Option B >>> working but I was not giving the points because I had not use send-label, >>> even though everything is working (which is why you don't notice any >>> problems :) >>> >>> Considering how picky is the script during the exam I would advise you to >>> use send-label for Option B. >>> >>> For what I've heard the script sometimes checks the output of >>> pre-determine >>> show commands, but as well seeks for specific entries in the >>> configuration, >>> so careful there. >>> >>> All the best, >>> Francisco >>> >>> >>> >>> >>> -----Original Message----- >>> From: [email protected] [mailto:[email protected]] On Behalf Of >>> Bryan Bartik >>> Sent: 07 August 2009 03:00 >>> To: [email protected]; [email protected] >>> Subject: Inter-AS VPN Option B and send-label >>> >>> I have seen some example of option B (ASBRs exchanging VPNv4 routes) and >>> send-label being used...however I have it working without it. I doubt it >>> is >>> needed because the ASBR's share their own local label for VPN routes with >>> each other and this put in their LFIB. The FEC is actually a VPNv4 route. >>> >>> Topology: >>> R1-R2 are AS100 >>> R6,R7 are AS200 >>> R3 is in VRF >>> R1 ---- R5 ---- | ---- R6 ---- R7 ---- vrf ---- R3 >>> >>> From R6: >>> Local Outgoing Prefix >>> 604 703 200:1:3.3.3.3/32 >>> >>> From R5: >>> Local Outgoing Prefix >>> 505 604 200:1:3.3.3.3/32 >>> >>> No routers have send-label and everything works fine. Is there a reason I >>> see send-label used with option B? >>> >>> -- >>> Bryan Bartik >>> CCIE #23707 (R&S), CCNP >>> Sr. Support Engineer - IPexpert, Inc. >>> URL: http://www.IPexpert.com >>> >>> _____________________________________________________________________ >>> Subscription information: http://www.groupstudy.com/list/comserv.html >>> >>> Checked by AVG - www.avg.com >>> Version: 8.5.392 / Virus Database: 270.13.16/2240 - Release Date: >>> 08/06/09 >>> 05:57:00 >>> >>> _____________________________________________________________________ >>> Subscription information: http://www.groupstudy.com/list/comserv.html >>> >>> >>> >>> >>> -- >>> Bryan Bartik >>> CCIE #23707 (R&S), CCNP >>> Sr. Support Engineer - IPexpert, Inc. >>> URL: http://www.IPexpert.com >>> >>> >>> _______________________________________________ >>> For more information regarding industry leading CCIE Lab training, please >>> visit www.ipexpert.com >>> >>> >>> >>> No virus found in this incoming message. >>> Checked by AVG - www.avg.com >>> Version: 8.5.409 / Virus Database: 270.13.76/2345 - Release Date: >>> 09/08/09 20:45:00 >>> >> >> >> >> -- >> Bryan Bartik >> CCIE #23707 (R&S), CCNP >> Sr. Support Engineer - IPexpert, Inc. >> URL: http://www.IPexpert.com >> > > -- Bryan Bartik CCIE #23707 (R&S), CCNP Sr. Support Engineer - IPexpert, Inc. 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