Configuring Igmp And Igmp Snooping - Extreme Networks 200 Series Installation And User Manual

IP Multicast Routing and IGMP Snooping
flooded to parts of the network that do not need it. The switch does not reduce any IP multicast traffic
in the local multicast domain (224.0.0.x).
If IGMP snooping is disabled, all IGMP and IP multicast traffic floods within a given VLAN. IGMP
snooping expects at least one device in the network to generate periodic IGMP query messages. Without
an IGMP querier, the switch stops forwarding IP multicast packets to any port.
When a port sends an IGMP leave message, the switch removes the IGMP snooping entry after 10
seconds. The switch sends a query to determine which ports want to remain in the multicast group. If
other members of the VLAN want to remain in the multicast group, the router ignores the leave
message, but the port that requests removal is removed from the IGMP snooping table.
If the last port within a VLAN sends an IGMP leave message, the router does not receive any responses
to the query, and the router immediately removes the VLAN from the multicast group.

Configuring IGMP and IGMP Snooping

Table 70 describes the commands used to configure IGMP and IGMP snooping on the Summit 200 series
switches.
Table 70: IGMP and IGMP Snooping Commands
Command
config igmp <query_interval>
<query_response_interval>
<last_member_query_interval>
config igmp snooping <router_timeout>
<host_timeout>
234
Description
Configures the IGMP timers. Timers are based
on RFC 2236. Specify the following:
• query_interval—The amount of time, in
seconds, the system waits between sending
out General Queries. The range is 1 to
2,147,483,647 seconds (68 years). The
default setting is 125 seconds.
• query_response_interval—The
maximum response time inserted into the
periodic General Queries. The range is 1 to
25 seconds. The default setting is 10 seconds.
• last_member_query_interval—The
maximum response time inserted into a
Group-Specific Query sent in response to a
Leave group message. The range is 1 to 25
seconds. The default setting is 1 second.
Configures the IGMP snooping timers. Timers
should be set to approximately 2.5 times the
router query interval in use on the network.
Specify the following:
• router_timeout—The interval, in seconds,
between the last time the router was
discovered and the current time. The range is
10 to 2,147,483,647 seconds (68 years). The
default setting is 260 seconds.
• host_timeout—The interval, in seconds,
between the last IGMP group report message
from the host and the current time. The range
is 10 to 2,147,483,647 seconds (68 years).
The default setting is 260 seconds.
Summit 200 Series Switch Installation and User Guide