Hi Rick,

Thanks for your quick reply.

Yes. I am doing Vol2 labs now and Yes. It covered inter-as.

But I want to know in Doccd (in case in exam if we stuck somewhere), where
the following topics are mentioned:
back-to-back VRF
LC-ATM
internet Access

Thanks,
Srinivas


On Wed, Dec 23, 2009 at 10:16 PM, Rick Mur <[email protected]> wrote:

> It's pretty easy.
>
> You make the 2 edge routers that connect each others AS a PE device. Then
> you take the link between the routers (for example Ethernet) and make a
> sub-interface (802.1Q tagged) for each VPN. Put that interface in the VRF of
> the VPN on both ends. Then run a dynamic protocol in each VRF to exchange
> the routes to the other end (could be anything, just PE-CE stuff, but now
> used as PE-PE).
>
> Our Workbook 1 has a lab about it, actually all 3 ways of doing Inter-AS
> VPNs are explained there. Also the Workbook 2 labs include every way of
> doing it in at least 1 lab (5 of the 10 are really focused on Inter-AS
> communications, so is the real SP lab).
>
> This page (they copied a chapter from MPLS Configuration on Cisco IOS, so
> technically it's illegal :-), explains every method in detail with configs
> and diagrams.
>
>
> http://mpls-configuration-on-cisco-ios-software.org.ua/1587051990/ch07lev1sec2.html
>
>
> --
> Regards,
>
> Rick Mur
> CCIE2 #21946 (R&S / Service Provider)
> Sr. Support Engineer – IPexpert, Inc.
> URL: http://www.IPexpert.com
>
> On 23 dec 2009, at 17:22, srinivas pv wrote:
>
> Hi,
>
> In Cisco online documentation, I saw config steps/examples for other
> inter-AS scenarios except back-to-back VRF (even though it was mentioned in
> other books etc, and is straight forward)
>
> Any idea, where can I find config steps/examples for back-to-back vrf on
> CCO.
>
> Also following topics:
> LC-ATM
> VPN internet access.
>
> Thanks,
> Srinivas
>
> On Wed, Dec 23, 2009 at 9:34 PM, Rick Mur <[email protected]> wrote:
>
>> Indeed, redistributing eBGP prefixes in the IGP would definitely work when
>> send-label is specified by the 2 ASBR eBGP routers. Than you should have an
>> end-to-end LSP between the PE's in both AS's.
>>
>> Then you configure multi-hop eBGP VPNv4 between the PE's and that way
>> distribute the VPN prefixes between the AS's, this is RFC2547bis Option C.
>>
>> The only way of doing Inter-AS VPN's WITHOUT any VPNv4 communication is
>> with Option A, which is a back-to-back VRF-lite configuration on ethernet
>> sub-interfaces or multiple FR DLCI or ATM VC sub-interfaces.
>>
>> --
>> Regards,
>>
>> Rick Mur
>> CCIE2 #21946 (R&S / Service Provider)
>> Sr. Support Engineer – IPexpert, Inc.
>> URL: http://www.IPexpert.com
>>
>> On 23 dec 2009, at 16:43, matt reath wrote:
>>
>> I've run into lab scenarios where an InterAS VPN needed to be established
>> w/o using the VPNv4 family between the eBGP neighbors. To get it to work
>> properly I configured send-labels on the eBGP neighbors and made sure that
>> each AS knew about the other AS's loopback addresses via BGP<->IGP
>> redistribution.  That way there is a label defined via LDP/IGP in each AS
>> for the other ASs loopack addresses. I used next-hop-self on the iBGP
>> neighbors but it still wouldn't build a complete LSP unless the other AS's
>> loopbacks were redistributed.
>>
>> On Mon, Dec 21, 2009 at 6:21 PM, Rick Mur <[email protected]> wrote:
>>
>>> Try and convince yourself why you would need to add the send-label. See
>>> what you are doing and if you know that the next-hop prefixes already have a
>>> label through IGP/LDP or do you need to allocate labels for the EBGP
>>> prefixes, it really depends on your implementation just like Bryan said. If
>>> next-hop-self is used for EBGP prefixes than the next-hop address already
>>> has a label allocated through the IGP and LDP, so no then you don't need
>>> send-label.
>>>
>>> Really convince yourself of doing something, rather than doing a 'best
>>> practice'. See how the LSP works and how things are allocated.
>>>
>>>  --
>>> Regards,
>>>
>>> Rick Mur
>>> CCIE2 #21946 (R&S / Service Provider)
>>> Sr. Support Engineer – IPexpert, Inc.
>>> URL: http://www.IPexpert.com
>>>
>>> On 21 dec 2009, at 21:35, Bryan Bartik wrote:
>>>
>>> Srinivas,
>>>
>>> If you are doing MP-EBGP between the ASBRs and using next-hop-self from
>>> the ASBRs to the internal peers, then you shouldn't need send-label at all.
>>> In this lab, NHS is configured in the PG so I think send-label is
>>> unnecessary.
>>>
>>> If you didn't use next-hop-self then you need to get that ASBR link into
>>> BGP and use send-label from ASBR to IBGP peers.
>>>
>>> On Mon, Dec 21, 2009 at 1:08 PM, srinivas pv <[email protected]
>>> > wrote:
>>>
>>>> Hi Team,
>>>>
>>>> I am doing this lab and I have the following query. Please do the
>>>> needful.
>>>>
>>>> This is inter-AS scenario, and the restriction is not to allow LDP on
>>>> any interconnecting links between networks.
>>>>
>>>> So we need to use send-label on the links between AS 100 and 200. Why do
>>>> we need to configure send-label for iBGP neighbors also?
>>>> Is interconnecting links means, here iBGP also?
>>>>
>>>>
>>>> Thanks,
>>>> Srinivas
>>>>
>>>> _______________________________________________
>>>> For more information regarding industry leading CCIE Lab training,
>>>> please visit www.ipexpert.com
>>>>
>>>>
>>>
>>>
>>> --
>>> Bryan Bartik
>>> CCIE #23707 (R&S, SP), 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
>>>
>>>
>>>
>>> _______________________________________________
>>> 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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