HP 6125G HP 6125G & 6125G/XG Blade Switches IP Multicast Configuration - Page 282

Configuring MLD query and response parameters globally, max-response-time, Command, Remarks

Page 282 highlights

query). The timer is initialized to a random value in the range of 0 to the maximum response delay advertised in the MLD query message. When the timer decreases to 0, the host sends an MLD membership report message to the IPv6 multicast group. To speed up the response of hosts to MLD queries and avoid simultaneous timer expirations causing MLD report traffic bursts, you must properly set the maximum response delay. • For MLD general queries, the maximum response delay is set by the max-response-time command. • For MLD multicast-address-specific query and multicast-address-and-source-specific query messages, the maximum response delay equals the last listener query interval. When multiple multicast routers exist on the same subnet, the MLD querier is responsible for sending MLD query messages. If a non-querier router receives no MLD query from the querier when the other querier present interval expires, it considers the querier as having failed and starts a new querier election. Otherwise, the non-querier resets the other querier present timer. To avoid frequent MLD querier changes, set the other querier present interval greater than the MLD query interval. To avoid incorrect multicast group member removals, set the MLD query interval greater than the maximum response delay for MLD general queries. Configuring MLD query and response parameters globally Step 1. Enter system view. 2. Enter MLD view. 3. Configure the MLD querier's robustness variable. 4. Configure the startup query interval. 5. Configure the startup query count. 6. Configure the MLD query interval. 7. Configure the maximum response delay for MLD general query messages. 8. Configure the MLD last listener query interval. Command system-view mld robust-count robust-value startup-query-interval interval startup-query-count value timer query interval Remarks N/A N/A 2 times by default. A higher robustness variable makes the MLD querier more robust but results in a longer IPv6 multicast group timeout time. By default, the startup query interval is 1/4 of the "MLD query interval". By default, the startup query count is set to the MLD querier's robustness variable. 125 seconds by default. max-response-time interval 10 seconds by default. last-listener-query-interval interval 1 second by default. 271

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query). The timer is initialized to a random value in the range of 0 to the maximum response delay
advertised in the MLD query message. When the timer decreases to 0, the host sends an MLD
membership report message to the IPv6 multicast group.
To speed up the response of hosts to MLD queries and avoid simultaneous timer expirations causing MLD
report traffic bursts, you must properly set the maximum response delay.
For MLD general queries, the maximum response delay is set by the
max-response-time
command.
For MLD multicast-address-specific query and multicast-address-and-source-specific query
messages, the maximum response delay equals the last listener query interval.
When multiple multicast routers exist on the same subnet, the MLD querier is responsible for sending MLD
query messages. If a non-querier router receives no MLD query from the querier when the other querier
present interval expires, it considers the querier as having failed and starts a new querier election.
Otherwise, the non-querier resets the other querier present timer.
To avoid frequent MLD querier changes, set the other querier present interval greater than the MLD query
interval.
To avoid incorrect multicast group member removals, set the MLD query interval greater than the
maximum response delay for MLD general queries.
Configuring MLD query and response parameters globally
Step
Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter MLD view.
mld
N/A
3.
Configure the MLD querier’s
robustness variable.
robust-count
robust-value
2 times by default.
A higher robustness variable
makes the MLD querier more
robust but results in a longer IPv6
multicast group timeout time.
4.
Configure the startup query
interval.
startup-query-interval
interval
By default, the startup query
interval is 1/4 of the "MLD query
interval".
5.
Configure the startup query
count.
startup-query-count
value
By default, the startup query count
is set to the MLD querier’s
robustness variable.
6.
Configure the MLD query
interval.
timer query
interval
125 seconds by default.
7.
Configure the maximum
response delay for MLD
general query messages.
max-response-time
interval
10 seconds by default.
8.
Configure the MLD last
listener query interval.
last-listener-query-interval
interval
1 second by default.