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 >
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