3Com Switch 8800 Family Configuration Guide

450 CHAPTER 42: IGMP CONFIGURATION
packets and the ACL rule bound to the VLAN, the switch determines whether to
discard the packets or let them pass.
By setting the filtering rule of multicast groups in the VLAN, you can control access
to IP multicast groups. You can only configure one ACL rule for each VLAN, and
the new configured rule will replace the old one.
Perform the following configuration in VLAN view.
By default, no filtering rule is set for a VLAN. In this case, a host can be joined to
any multicast group.
c
CAUTION:
■ If an inexistent acl-number is bound to the VLAN, or if the bound acl-number is
not configured with a rule, a host is still allowed to join any multicast group.
■ The multicast group filtering rule is not restricted by the ACL itself, and is valid
for all members in the specified VLAN.
Enabling/Disabling IGMP
Fast Leave
An IGMP-enabled Layer 3 switch does not query packets of the specific multicast
group to a fast leave-enabled port any longer when the port receives an IGMP
leave packet. Instead, the switch removes the port from the outbound port lists of
all Layer 3 multicast forwarding tables that are of the same multicast group to peel
off the port from the multicast group. That is, the switch does not send specific
query packet to the port or forward multicast data to the port.
Perform the following configuration in Ethernet port view or system view.
For detailed configuration, refer to the 3Com Switch 8800 Family Series Routing
Switches Command Manual.
n
Tabl e 444 Configure the aging time of multicast group members
Operation Command
Set the filtering rule of multicast groups in the
specified VLAN
igmp-snooping group-policy acl-number
Cancel the filtering rule of multicast groups in
the specified VLAN
undo igmp-snooping group-policy
Tabl e 445 Enable/Disable IGMP fast leave
Operation Command Remarks
Enter system view system-view -
Enable IGMP fast leave in
system view
igmp fast-leave [ vlan { vlan-id [ to
vlan-id ] } &<1-10> ]
IGMP fast leave is
disabled by default
Enter Ethernet port view
interface interface-type
interface-number
-
Enable IGMP fast leave in
Ethernet port view
igmp fast-leave [ vlan { vlan-id [ to
vlan-id ] } &<1-10> ]
IGMP fast leave is
disabled by default
Disable IGMP fast leave
undo igmp fast-leave [ vlan {
vlan-id [ to vlan-id ] } &<1-10> ]
-