Dell FCX624-E Laptop User Manual


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896 PowerConnect B-Series FCX Configuration Guide
53-1002266-01
Configuring MLD snooping
27
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.
PowerConnect(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.
PowerConnect(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 a command such as the following.
PowerConnect(config)#ipv6 mld-snooping verbose-off
Syntax: [no] ipv6 mld-snooping verbose-off
Configuring the MLD mode for a VLAN
You can configure a VLAN for either the active or passive (default) MLD mode. The VLAN setting
overrides the global setting:
Active – In active MLD mode, a device actively sends out MLD queries to identify IPv6 multicast
groups on the network, and makes entries in the MLD table based on the group membership
reports it receives from the network.
Passive – In passive MLD mode, the device forwards reports to router ports which receive
queries. MLD snooping in the passive mode does not send queries. However, it does forward
queries to the entire VLAN.
To set the MLD mode for VLAN 20 to active, enter the following commands.
PowerConnect(config)#vlan 20
PowerConnect(config-vlan-20)#mld-snooping active
Syntax: [no] mld-snooping active | passive