Multicast Imaging

[acshearer]

Hello,

I am trying to get multicast imaging to work on my Alcatel-Lucent switches but it is not working. It starts the image process but just sits there and does not pass the data. If I hook my computers to the Cisco Switches in those closets (I have a mix of Layer 2 Cisco 2960G and Alcatel-Lucent OS6450 in my IDFs) everything works fine and the computers will image successfully. Because they work with the Cisco switches there has to be something on the Alcatel-Lucent switches that I don't have configured correctly. All multicast imaging traffic is on the same VLAN. I have all of Multicast switching enabled for VLAN 1 (which is the vlan of my computers). What all needs to be configured for Multicast imaging to work with these switches or can you point me to some good documentation for this? I am new to Alcatel-Lucent so I don't have a lot of knowledge of the configuration process. My Core Layer 3 routers in each building are Cisco 3560Gs.

Thanks,
Andrew
Network Administrator
West York Area School District

[silvio]

Hi,
at all you switches:
ip multicast status enable

at the switch with the ip-interface in that vlan (but you can also this use in all switches):
ip multicast querying enable

if the switch with the mc-source is not the querier (switch with ip interface in that vlan) than you need this command (but you can also this use in all switches):
ip multicast querier-forwarding enable

regards
Silvio

[acshearer]

Hello Silvio

Thanks for the commands. I will put them in and see if everything works after that. I will post back my results.

Thanks,
Andrew

[Rens]

Hello Andrew and Silvio,

@Andrew, Did the commands mentioned by Silvo solve your issue?

@Silvo, Do you know what do the commands "ip multicast querier-forwarding enable" and "ip multicast querying enable" do with the igmp packets?
What I've seen so far is that when multicast status is enabled and the clients send an igmp join a multicast group is formed. (show ip multicast group)

The reason I'm asking is because currently I'm working on an installation with a lot of multicast video traffic and I'm trying to understand multicast switching and multicast routing in a litle more depth.

With kind regards,

Rens

[silvio]

ip multicast querying enable - this you need only at the querier. Querier is the switch with an ip-interface in the vlan. Normaly the MC-clients sent an IGMP packet to join a MC-group only one time. After some minutes the group association will ages out without any querier and the MC-stream will be finished (if MC is enabled). The querier holds the group association between mc-server and mc-client (querier intervall).
If the mc-server is not attached direct at a querier (with an ip interface) you need querier forwarding at this switch(es) between querier and server. The igmp will be forwarded from the querier to the server.
regards
Silvio

[Rens]

Hello Silvio,

Thanks for the explanation.

Regards,

Rens