Show Connected Multicasts

Jun 2017

To show if an interface is actively listening to any multicast streams, we can show this by using the netstat command: (netstat -ng)

netstat -ng
IPv6/IPv4 Group Memberships
Interface RefCnt Group
--------------- ------ ---------------------
lo 1 224.0.0.1
eth2 4 239.0.200.1
eth2 1 224.0.0.1
eth3 1 224.0.0.1
eth4 1 224.0.0.1
eth5 1 224.0.0.1
eth0 1 224.0.0.1
eth1 1 224.0.0.1
lo 1 ff02::1
eth2 1 ff02::1
eth3 1 ff02::1
eth4 1 ff02::1
eth5 1 ff02::1
eth0 1 ff02::1
eth1 1 ff02::1

This is a packager (v8) that I have setup a service on. That service is an ABR service containing four streams, so the line:
eth2 4 239.0.200.1\
Is interesting to me, I can see that from address 239.0.200.1 (the MFEL multicast output) Interface 2 is connected to four multicasts.