Inter-AS multicastVPN

[devang_etcom]

Does pim Sparse-mode support the inter-as multicast VPN?

i guess only PIM SSM supports the multicast vpn in inter-as configuration... just to cross check...

regards

Devang Patel

[Harold Ritter]

Chintan,

You are correct on your explanation.

And about BGP free core, This requires RPF Vector support, wich is not supported either by Juniper.

Regards

[shivlu jain]

As per my understanding RPF vector means that the PE will act as proxy becasue the downstream is not having any information for the upstream. We can also say that in single MPLS domain also my PE works as RPF vector.

regards

shivlu jain

[Harold Ritter]

Devang,

As indicated by Chintan, you do not need to leak PEs loopback addresses from one AS to the other with option 10b. You will need support for the BGP MDT SAFI, the connector attribute and the RPF Vector though, as explained in the following document:

http://www.cisco.com/en/US/docs/ios/12_0s/feature/guide/iasmcvpn.html

Regards

[devang_etcom]

Hritter,

Agree that in option B we dont need to leak loopback! but I am just curious to know, will it work if I will leak loopbacks? If i will leak loopback then do I need to use BGP MDT SAFI?

thanks,

Devang Patel

[Harold Ritter]

Devang,

If you leak PE loopback addresses from one AS to the other, you will not need the MDT SAFI but you will still the connector attribute, as the next hop attribute for the BGP VPNv4 updates will be set to the ASBR rather than originating PE, which will cause the RPF check to fail.

Regards

[devang_etcom]

Hritter,

Thanks for your quick response; but again the configuration wise there will be no any difference right? or i guess now i just need to enable the address family IPv4 multicast instead of address family MDT; am i correct?

thanks

Devang Patel

[Harold Ritter]

Devang,

If the MDT SAFI is not used then it means that you will have to use ASM, which implies an RP in each AS and MSDP between the two.

Again, I assume this is not a multi vendor environment, as the connector attribute is not supported by JUNOS.

Regards

[devang_etcom]

Hritter,

Yes I am talking about only CISCO implementation! so back to configuration: do we need only BGP IPv4 multicast address family or don't even need that?

thanks

Devang Patel

[Harold Ritter]

Devang,

You do not need AF ipv4 multicast, just AF ipv4 unicast to leak the loopback addresses between ASes.

Since it is a Cisco only network, why don't you go with the MDT SAFI. This would make your life way easier and more in line with best practices as well.

Regards

[devang_etcom]

The issue I have is I dont have an IOS that support MDT SAFI! thats why I am looking for alternate path! Yeah we can leak loopback routes with address family IPv4 unicast! then only thing I wanted to understand the how RPF will work here in this case if we will not have address family MDF and Multicast! becoz many time i found the RPF fail issue! so it will be great if you can explain me how things work in my case?

I know you are the person from whom I will have answer! ;-)

thanks,

Devang Patel

[Harold Ritter]

Devang,

If you do not have the IOS required to support the MDT SAFI, you do not have the IOS to support the connector attribute either. This will cause the RPF check to fail on the PE where the receiver is connected.

I would recommended either upgrading the IOS to support the MDT SAFI, RPF vector and connector attribute. The other option is to use option 10a or 10c, which will not required any of these features.

Regards

[Harold Ritter]

Shivlu,

I guess you meant that the VPNv4 type 2 RD is used for intra-AS, not inter-AS.

Regards

[shivlu jain]

hritter

yes because in the previos ios cisco is attahcing type 2 rd which is not as per standard but in SB and SRC series cisco added mdt safi feature. If we want to go for inter as mVPN then the core should be migrated to mdt-safi means which is not using type 2 rd in mvpn.

regards

shivlu jain

[Harold Ritter]

Shivlu,

I was merely pointing out that you wrote inter-area instead of intra-area.

Regards

[shivlu jain]

curently most of the cisco ios are using type 2 rd for intra-AS which is actually not standard.

regards

shivlu jain