Thanks Shaughn,

Why do I need labels for the loopbacks between the ASs? The eBGP peering
between the ASBRs is over the directly connected network - so didnt think
there was any need for each AS to know about the others internal addressing.

Im just starting to go through these, so maybe I am missing something
somewhere.

Jo

2009/9/9 Shaughn Smith <[email protected]>

> You are more than likely getting the labels for the VPNV4 routers, but what
> about IP's that are in the global table, ie the Loopbacks etc. As far as i
> am aware you need to enable an IPV4 session with the send-label command to
> get labels for the routes in the Global routing table, not just the routes
> in  that specific VRF.
>
>
> On Wed, Sep 9, 2009 at 10:45 AM, Jo Knight <[email protected]> wrote:
>
>> 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 <http://www.ipexpert.com/>
>>>>
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>>>>
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>>>
>>>
>>>
>>> --
>>> Bryan Bartik
>>> CCIE #23707 (R&S), CCNP
>>> Sr. Support Engineer - IPexpert, Inc.
>>> URL: http://www.IPexpert.com <http://www.ipexpert.com/>
>>>
>>> _______________________________________________
>>> For more information regarding industry leading CCIE Lab training, please
>>> visit www.ipexpert.com
>>>
>>>
>>
>> _______________________________________________
>> For more information regarding industry leading CCIE Lab training, please
>> visit www.ipexpert.com
>>
>>
>
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