Enabling The Pseudo-Querier; Changing Igmp Timers - D-Link DWS-1008 - AirPremier MobileLAN Switch Product Manual

Enabling the Pseudo-Querier

The IGMP pseudo-querier enables IGMP snooping to operate in a VLAN that does not have a multicast
router to send IGMP general queries to clients.
Note: D-Link recommends that you use the pseudo-querier only when the VLAN contains local multicast
traffic sources and no multicast router is servicing the subnet.
To enable the pseudo-querier, use the following command:
set igmp querier {enable | disable} [vlan vlan-id]
You can change the following IGMP timers:
• Query interval—Number of seconds that elapse between general queries sent by the
switch to advertise multicast groups.
• Other-querier-present interval—Number of seconds that the switch waits for a general
query to arrive from another querier before electing itself the querier.
• Query response interval—Number of tenths of a second that the switch waits for a receiver
to respond to a group-specific query message before removing the receiver from the
receiver list for the group.
Note: The query interval, other-querier-present interval, and query response interval are
applicable only when the switch is querier for the subnet. For the switch to become the
querier, the pseudo-querier feature must be enabled on the switch and the switch must
have the lowest IP address among all the devices eligible to become a querier. To enable
the pseudo-querier feature, see "Enabling the Pseudo-Querier".
• Last member query interval—Number of tenths of a second that the switch waits for a
response to a group-specific query after receiving a leave message for that group, before
removing the receiver that sent the leave message from the list of receivers for the group.
If there are no more receivers for the group, the switch also sends a leave message for the
group to multicast routers.
• Robustness value—Number used as a multiplier to adjust the IGMP timers to the amount
of traffic loss that occurs on the network. Set the robustness value higher to adjust for more
traffic loss.
D-Link DWS-1008 User Manual

Changing IGMP Timers

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