Configuring Ipv6 Multicast Group Replacement - H3C S3610-28P Operation Manual

Operation Manual – Multicast Protocol
H3C S3610&S5510 Series Ethernet Switches
Note:
When the number of IPv6 multicast groups that can be joined on a port reaches the
maximum number configured, the system deletes all the forwarding entries
persistent to that port from the MLD Snooping forwarding table, and the hosts on
this port need to join IPv6 multicast groups again.
If you have configured static or simulated joins on a port, however, when the number
of IPv6 multicast groups on the port exceeds the configured threshold, the system
deletes all the forwarding entries persistent to that port from the MLD Snooping
forwarding table and applies the static or simulated joins again, until the number of
IPv6 multicast groups joined by the port comes back within the configured threshold.

3.6.6 Configuring IPv6 Multicast Group Replacement

For some special reasons, the number of IPv6 multicast groups passing through a
switch or port may exceed the number configured for the switch or the port. In addition,
in some specific applications, an IPv6 multicast group newly joined on the switch needs
to replace an existing IPv6 multicast group automatically. A typical example is "channel
switching", namely, by joining the new multicast, a user automatically switches from the
current IPv6 multicast group to the one.
To address this situation, you can enable the IPv6 multicast group replacement function
on the switch or certain ports. When the number of IPv6 multicast groups a switch or a
port has joined exceeds the limit.
If the IPv6 multicast group replacement is enabled, the newly joined IPv6 multicast
group automatically replaces an existing IPv6 multicast group with the lowest IPv6
address.
If the IPv6 multicast group replacement is not enabled, new MLD reports will be
automatically discarded.
I. Configuring IPv6 multicast group replacement globally
Follow these steps to configure IPv6 multicast group replacement globally:
Enter system view
Enter MLD Snooping view
Configure IPv6 multicast
group replacement
To do...
system-view
mld-snooping
overflow-replace [ vlan
vlan-list ]
Chapter 3 MLD Snooping Configuration
Use the command...
3-19
Remarks
—
—
Required
Disabled by default