Configuration Guide User guide

1638 FastIron Configuration Guide
53-1002494-02
MLD snooping configuration
You can configure report control to rate-limit report forwarding for the same group to no more than
once per 10 seconds. This rate limiting does not apply to the first report answering a group-specific
query.
NOTE
This feature applies to MLDv1 only. The leave messages are not rate limited.
MLDv1 membership reports for the same group from different clients are considered to be the
same, and are rate-limited. This alleviates the report storm caused by multiple clients answering
the upstream router query. To enable report-control, use the ipv6 mld-snooping report-control
command.
Brocade(config)#ipv6 mld-snooping report-control
Syntax: [no] ipv6 mld-snooping report-control
Modifying the wait time before stopping traffic when
receiving a leave message
You can define the wait time before stopping traffic to a port when the device receives a leave
message for that port. The device sends group-specific queries once per second to determine if any
client on the same port still needs the group. The value range is from 1 to 5, and the default is 2.
Due to the internal timer accuracy, the actual wait time is between n and (n+1) seconds, where n is
the configured value.
Brocade(config)#ipv6 mld-snooping leave-wait-time 1
Syntax: [no] ipv6 mld-snooping leave-wait-time <num>
Modifying the multicast cache (mcache) aging time
You can set the time for an mcache to age out when it does not receive traffic. The traffic is
hardware-switched. One minute before an mcache is aged out, the device mirrors a packet of the
mcache to the CPU to reset the age. If no data traffic arrives within one minute, the mcache is
deleted. If you configure a lower value, the resource consumed by idle streams is quickly removed,
but packets are mirrored to the CPU more frequently. Configure a higher value only when data
streams are arriving consistently. The range is 60 to 3600 seconds, and the default is 60 seconds.
Brocade(config)#ipv6 mld-snooping mcache-age 180
Syntax: [no] ipv6 mld-snooping mcache-age <num>
Disabling error and warning messages
The device prints error or warning messages when it runs out of software resources or when it
receives packets with the wrong checksum or groups. These messages are rate limited. You can
turn off these messages by entering the ipv6 mld-snooping verbose-off command.
Brocade(config)#ipv6 mld-snooping verbose-off
Syntax: [no] ipv6 mld-snooping verbose-off