MSDP Query

eborgard

Hi.

I have a question about MSDP.  Suppose the following basic topology.

R1----MSDP Peer----R2

What is the difference between the two commands that call ACL 111

 

access-list 111 deny ip any host 224.0.2.2

access-list 111 deny ip any host 224.0.1.3

access-list 111 deny ip any host 224.0.1.24

access-list 111 deny ip any host 224.0.1.22

access-list 111 deny ip any host 224.0.1.2

access-list 111 deny ip any host 224.0.1.60

 

ip msdp sa-filter out <peer address> list 111

ip msdp redistribute list 111

 

 

Narayan.Neupane

Hi,

access-list 111 deny ip any host 224.0.x.x

In your example the ip msdp redistribute command referencing  access list 111, which permits any source prefixes and group address prefixes 224.x.x.x . Any source can still register with the local  RP to any multicast group but only to those groups are advertised in SA messages. Remember that this applies to  locally originated SA messages not received from remote MSDP Peer.

ip msdp sa-filter out|in : filters all SA messages, whether locally originated or received from another MSDP peer.

Good Luck

dcancerian

ip msdp sa-filter out <peer address> list 111

With the help of this command we can control all out going sa messages(multicast sources and groups).

ip msdp redistribute list 111

This command controls the sources and groups of locally originated so its like a subset of the above command.

http://www.cisco.com/en/US/docs/ios/ipmulti/command/reference/imc_03.html#wp1060945

eborgard

Thanks a bunch!

markus.wirth

This command controls the sources and groups of locally originated so its like a subset of the above command.

Hmm...what are locally originated ones??? You mean multicast groups belonging to the router itself? Which ones arte those?

Ist it recommended to use both or just one of the two? Have no experience with that command at the moment.

 

TIA!

 

Regards!

Markus

Narayan.Neupane

Hmm...what are locally originated ones??? You mean multicast groups belonging to the router itself? Which ones arte those?

This reference to the originated from Local Domain, ip msdp redistribute control this.

dcancerian

This command controls the sources and groups of locally originated so its like a subset of the above command.

Hmm...what are locally originated ones??? You mean multicast groups belonging to the router itself? Which ones arte those?

As mentioned by Narayan, here local means sources originated within the domain or as AS.

 

markus.wirth

Ok so the SA filter also filters all messages including from MSDP Peer One (AS1) going to MSDP Peer Two (AS2) and the redistribute list let those packets traverse and just filters the ones originated from the own AS?

 

TIA!

Regards!

Markus

dcancerian

Ok so the SA filter also filters all messages including from MSDP Peer One (AS1) going to MSDP Peer Two (AS2) and the redistribute list let those packets traverse and just filters the ones originated from the own AS?

Yes thats right, you can also refer Cisco DoC its mentioned there in simple terms.

markus.wirth

Ok I will check that! Thanks for the clearification in that case! Then I know whats to do!

Regards!

Markus

markus.wirth

Ok thanks for the clearification here! Then I know what to do!

Will check the DocCD.

 

Regards!

Markus

Narayan.Neupane

Hi Markus,

 

Here is  example with some explanation

http://www.cisco.com/en/US/tech/tk828/technologies_tech_note09186a0080093fda.shtml

http://andrew.triumf.ca/AG/multicast/Multicast-Command-Reference.html

Good Luck

dcancerian

Hi Markus,

 

Here is one example with some explanation

Good Luck

You missed the link here [:)]

 

markus.wirth

Yeah link would be cool i am curious about a scenario.

Thanks in advance for that info!