D-Link DGS-3224TGR Command Line Interface Reference Manual page 96

config igmp_snooping querier
Purpose Used to configure the time in seconds between general query transmissions, the maximum
time in seconds to wait for reports from members, the permitted packet loss that guarantees
IGMP snooping.
Syntax config igmp_snooping querier [<vlan_name 32>|all]
{query_interval <sec 1-65535>|max_response_time <sec 1-25>|robustness_variable
<value 1-255>|last_member_query_interval <sec 1-65535>|state [enable|disable]
This command configures IGMP snooping querier.
Description
<vlan_name 32> − The name of the VLAN for which IGMP snooping querier is to be
Parameters
configured.
query_interval <sec 1-65535> − Specifies the amount of time in seconds between general
query transmissions. The default setting is 125 seconds.
max_response_time <sec 1-25> − Specifies the maximum time in seconds to wait for reports
from members. The default setting is 10 seconds.
robustness_variable <value 1-255> − Provides fine-tuning to allow for expected packet loss on
a subnet. The value of the robustness variable is used in calculating the following IGMP
message intervals:
last_member_query_interval <sec 1-65535> − The maximum amount of time between group-
specific query messages, including those sent in response to leave-group messages. You
might lower this interval to reduce the amount of time it takes a router to detect the loss of the
last member of a group.
state [enable|disable] − Allows the switch to be specified as an IGMP Querier or Non-querier.
Restrictions Only administrator-level users can issue this command.
Example Usage:
To configure IGMP snooping:
DGS-3224TGR Gigabit Ethernet Switch CLI Reference Manual
•
Group member interval—Amount of time that must pass before a multicast router
decides there are no more members of a group on a network. This interval is
calculated as follows: (robustness variable x query interval) + (1 x query response
interval).
•
Other querier present interval—Amount of time that must pass before a multicast
router decides that there is no longer another multicast router that is the querier. This
interval is calculated as follows: (robustness variable x query interval) + (0.5 x query
response interval).
•
Last member query count—Number of group-specific queries sent before the router
assumes there are no local members of a group. The default number is the value of
the robustness variable.
•
By default, the robustness variable is set to 2. You might want to increase this value if
you expect a subnet to be lossy.
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