http://en.community.dell.com/support-forums/network-switches/f/866/t/19677497

http://en.community.dell.com/support-forums/network-switches/f/866/t/19650967

http://www.dell.com/Support/Article/us/en/04/SLN295739

# vlan20是组播vlan, 192.168.50.227接在Gi1/0/40接口

vlan 20

exit

interface vlan 20

ip address 192.168.50.227 255.255.255.0

exit 

interface range Gi1/0/25-40

switchport access vlan 20

exit

# 禁用默认、公网、内网vlan的igmp snoop

no ip igmp snooping vlan 1

no ip igmp snooping vlan 10

no ip igmp snooping vlan 30

ip igmp snooping vlan 20 mrouter interface Gi1/0/40

ip igmp snooping querier

ip igmp snooping querier address 192.168.50.227

ip igmp snooping querier query-interval 120

ip igmp snooping querier timer expiry 300

ip igmp snooping querier vlan 20

ip igmp snooping querier vlan 20 address 192.168.50.227

ip igmp snooping querier election participate 20

没有开启客户端时，服务器接收不到upd流，开启客户端后，能够接到组播流，说明组播抑制生效。

tcpdump -i em2 -nn udp

tcpdump -i em2 igmp