Concept Guide
ipv6 mld query-interval
Reducing Host Response Burstiness
General Queries contain a Query Response Interval value, which is the amount of time the host has to respond to a general query. Hosts
set a timer to a random number less than the Query Response Interval upon receiving a general query, and send a report when the timer
expires. Increasing this value spreads host responses over a greater period of time, and so reduces response burstiness.
To adjust the query response time, use the following command:
INTERFACE Mode
ipv6 mld query-max-resp-time
Clearing MLD groups
Clear a specic group or all groups on an interface from the multicast routing table.
To clear MLD groups, use the following command:
EXEC Privilege
clear ipv6 mld groups
Debugging MLD
Display Dell Networking OS messages about the MLD process.
To display debugging messages, use the following command:
EXEC Privilege
debug ipv6 mld
Explicit Tracking
If the Querier does not receive a response to a Multicast-Address-Specic Query, it sends another. Then, after no response, it removes the
group entry from the group membership table. You can congure the system to remove specied groups immediately after receiving a
Leave message to reduce leave latency.
To congure the system to remove a group immediately after receiving a Leave message, use the following command:
INTERFACE Mode
ipv6 mld explicit-tracking
Reducing Leave Latency
Leave Latency is the amount of time after the last host leaves the MLD group that the router stops forwarding trac for that group.
Latency is introduced because the router attempts several times to determine if there are any remaining members before stopping trac
for the group. The Querier sends a Multicast-Address-Specic Query upon receiving a Done message to ascertain whether there are any
remain receivers for a group. The Last Listener Query Interval is the Maximum Response Delay for a Multicast-Address-Specic Query, and
also the amount of time between Multicast-Address-Specic Query retransmissions. Lowering the Last Listener Query Interval reduces the
time to detect that there are no remaining receivers for a group, and so can reduce the amount of unnecessarily forwarded trac.
To adjust the last-member query interval, use the following command:
INTERFACE Mode
Multicast Listener Discovery Protocol
653