I’ve been doing a lot of playing with multicast lately and I always have to google for a while to find these commands. I figured it was time to throw a post together for a quick reference. Hopefully someone else can benefit from this too.
Below you can find the commands to determine whether a system or switch port is a member of a multicast group on Cisco IOS, windows and linux. Multicast uses IGMP to join these groups and there is no way to join a group manually. The operating system does it automatically when an application requests it so these commands can come in handy when you’re trying to figure out why you’re not seeing the multicast traffic that you’re expecting.
Cisco IOS:
show ip igmp snooping groups
Windows:
netsh interface ip show joins
Linux:
ip maddress show
or
netstat -ng