OS6250 does not see multicast neighbors
Posted: 10 Mar 2015 13:41
This is more of an FYI than asking for assistance.
If you enable multicast switching on an OS6250, it will only see multicast neighbors (PIM/DVMRP routers) on VLANs that it has an IP interface on. This is different behavior than the OS6850 or other "true" layer 3 switches.
I opened a PR with Alcatel-Lucent on this. They confirmed behavior, and recently told me that this is "expected." Nowhere in the OS6250 manual does it say that an IP interface is necessary to learn multicast neighbors.
Bear in mind that if there are no neighbors, the switch won't forward multicast frames out uplinks to core or distribution switches. This means no forwarding, which will break applications like Ghost, Samsung MagicInfo, and HP printer discovery, just to name a few.
If you enable multicast switching on an OS6250, it will only see multicast neighbors (PIM/DVMRP routers) on VLANs that it has an IP interface on. This is different behavior than the OS6850 or other "true" layer 3 switches.
I opened a PR with Alcatel-Lucent on this. They confirmed behavior, and recently told me that this is "expected." Nowhere in the OS6250 manual does it say that an IP interface is necessary to learn multicast neighbors.
Bear in mind that if there are no neighbors, the switch won't forward multicast frames out uplinks to core or distribution switches. This means no forwarding, which will break applications like Ghost, Samsung MagicInfo, and HP printer discovery, just to name a few.