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
>>
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>
>
>
> --
> 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
>
>
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