HP 4500G PWR 24-Port, Руководство по настройке

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Configuration Prerequisites
Before adjusting IGMP performance, complete the following tasks:
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Configure any unicast routing protocol so that all devices in the domain are interoperable at the
network layer.
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Configure basic functions of IGMP
Before adjusting IGMP performance, prepare the following data:
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Startup query interval
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Startup query count
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IGMP general query interval
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IGMP querier’s robustness variable
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Maximum response time for IGMP general queries
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IGMP last-member query interval
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Other querier present interval
Configuring IGMP Message Options
IGMP queries include group-specific queries and group-and-source-specific queries, and multicast
groups change dynamically, so a device cannot maintain the information for all multicast sources and
groups, For this reason, when receiving a multicast packet but unable to locate the outgoing interface
for the destination multicast group, an IGMP router needs to leverage the Router-Alert option to pass
the multicast packet to the upper-layer protocol for processing. For details about the Router-Alert option,
refer to RFC 2113.
An IGMP message is processed differently depending on whether it carries the Router-Alert option in
the IP header:
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By default, for the consideration of compatibility, the device does not check the Router-Alert option,
namely it processes all the IGMP messages it received. In this case, IGMP messages are directly
passed to the upper layer protocol, no matter whether the IGMP messages carry the Router-Alert
option or not.
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To enhance the device performance and avoid unnecessary costs, and also for the consideration
of protocol security, you can configure the device to discard IGMP messages that do not carry the
Router-Alert option.
Configuring IGMP packet options globally
Follow these steps to configure IGMP packet options globally:
To do... Use the command... Remarks
Enter system view
system-view
—
Enter IGMP view
igmp
—
Configure the router to discard
any IGMP message that does
not carry the Router-Alert
option
require-router-alert
Optional
By default, the device does not
check the Router-Alert option.
Enable insertion of the
Router-Alert option into IGMP
messages
send-router-alert
Optional
By default, IGMP messages
carry the Router-Alert option.