Configuring Igmp Query And Response Parameters - HP A8800 Configuration Manual

Step
2. Enter public network IGMP
view or VPN instance IGMP
view.
3. Configure the router to
discard any IGMP message
that does not carry the
Router-Alert option.
4. Enable insertion of the
Router-Alert option into IGMP
messages.
Configuring Router-Alert option handling methods on an interface
Step
1. Enter system view.
2. Enter interface view.
3. Configure the interface to
discard any IGMP message
that does not carry the
Router-Alert option.
4. Enable insertion of the
Router-Alert option into IGMP
messages.

Configuring IGMP query and response parameters

On startup, the IGMP querier sends IGMP general queries at the startup query interval, which is
one-quarter of the IGMP general query interval. The number of queries, or the startup query count, is user
configurable.
After startup, the IGMP querier periodically sends IGMP general queries at the IGMP general query
interval to check for multicast group members on the network. You can modify the IGMP general query
interval based on actual condition of the network.
The IGMPv2 querier sends IGMP group-specific queries at the IGMP last-member query interval when it
receives an IGMP leave message. The IGMPv3 querier sends IGMP group-and-source-specific queries at
the IGMP last-member query interval when it receives a leave message or a report that changes the
multicast group and source mapping. The number of queries, or the last-member query count, equals the
robustness variable—the maximum number of packet retransmissions.
A receiver host starts a delay timer for each multicast group it has joined when it receives an IGMP query
(general query, group-specific query, or group-and-source-specific query). The timer is initialized to a
random value in the range of 0 to the maximum response time derived from the IGMP query. When the
timer value decreases to 0, the host sends an IGMP report to the corresponding multicast group.
To speed up the response of hosts to IGMP queries and avoid simultaneous timer expirations causing
IGMP report traffic bursts, you must correctly set the maximum response time.
For IGMP general queries, the maximum response time is set by the max-response-time command.
•
Command
igmp [ vpn-instance
vpn-instance-name ]
require-router-alert
send-router-alert
Command
system-view
interface interface-type
interface-number
igmp require-router-alert
igmp send-router-alert
94
Remarks
N/A
By default, the device does not
check the Router-Alert option.
By default, IGMP messages carry
the Router-Alert option.
Remarks
N/A
N/A
By default, the device does not
check the Router-Alert option.
By default, IGMP messages carry
the Router-Alert option.