Using ifconfig command you see if multicasting is enabled for your network interface or not. [ali@lab ~]$ /sbin/ifconfig wlan0 wlan0     Link encap:Ethernet  HWaddr 00:24:D7:38:D5:7C inet addr:172.30.59.189  Bcast:172.30.59.255  Mask:255.255.255.0 inet6 addr: fe80::224:d7ff:fe38:d57c/64 Scope:Link UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1 RX packets:761458 errors:0 dropped:0 overruns:0 frame:0 TX packets:282314 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:334033669 (318.5 [...]