Table of Contents
Advertisement
Multicast
Configuring IGMP Snooping
STEP 1
STEP 2
STEP 3
STEP 4
STEP 5
Cisco Small Business SG200 Series 8-port Smart Switches Administration Guide
IGMP snooping enables the switch to intercept membership reports from IGMP
clients and queries from routers. If the intercepted communications indicate that
no IGMP clients exist on a link for a particular multicast destination address within
a VLAN, then the switch does not send copies of those multicast packets to that
network segment.
IGMP snooping can be enabled or disabled on each VLAN. When enabled on a
VLAN, IGMP snooping is performed on all interfaces that are members of that
VLAN.
Although IGMP is based on IP multicast addresses, the switch performs the actual
multicast forwarding based on the equivalent MAC addresses.
To configure IGMP snooping:
Click Multicast > IGMP Snooping in the navigation window.
Select Enable for the IGMP Snooping Status.
Click Add in the IGMP Snooping Table.
For VLAN ID, select the VLAN that is to support IGMP snooping.
Configure the following settings:
•
IGMP Fast Leave—Select Enable to allow the switch to immediately remove
a port (or LAG) from its multicast forwarding table when it receives an IGMP
leave message for that multicast group. When enabled, the switch removes
the port without first sending out general queries to the interface. Enable Fast
Leave mode only on VLANs where only one host is connected to each port.
This prevents the inadvertent dropping of the other hosts that are connected
to the same port and remain interested in receiving multicast traffic directed
to that group.
•
IGMP Group Membership Interval—Specify the time in seconds that the
switch waits for an IGMP membership report from a particular group on a
particular interface before deleting the interface from the multicast
forwarding database entry. Select Default to specify 260 seconds, or select
User Defined and enter a value in the range 2 to 3600 seconds.
•
IGMP Max Response Time—Specify the time in seconds that the switch
waits for a reply after sending a query on an interface because it did not
receive a report for a particular group in that interface. This value must be
less than the IGMP Group Membership Interval value. Select Default to
specify 10 seconds, or select User Defined and enter a value in the range 1
to 25 seconds.
9
125
Advertisement
Table of Contents
