58 | SHOW IP ADVERTISE | Patch Release Note |
Note that IPv6 multicast packets will flood the VLAN when MLD snooping is disabled.
To enable MLD snooping, use the command:
ENABLE MLDSNOOPING
To display debugging information, use the command:
ENABLE MLDSNOOPING DEBUG
This command displays the ports that are currently receiving MLD packets and the ports that are being added or taken off the switch’s multicast group membership registration.
To disable debugging, use the command:
DISABLE MLDSNOOPING DEBUG
To display information about MLD snooping, use the command:
SHOW MLDSNOOPING COUNTER
For more information, including limitations on which addresses and packet types can be snooped, see the IPv6 Multicasting chapter of the Software Reference.
Ping Polling of Device Reachability
This enhancement enables the router or switch to regularly check whether or not it can reach a device. It also enables a trigger to activate on the router or switch when the device becomes unreachable. While the device is unreachable, the router or switch continues to monitor the device’s reachability, and another trigger can be set to activate when the device becomes available again. For example, the first trigger’s script could open and configure an alternative link if the device at the other end of a preferred link became unavailable. The second trigger’s script would automatically return traffic to the preferred link as soon as it was available again.
To determine the device’s reachability, the router or switch will regularly send ICMP Echo Request packets (“pings”) to the device. As long as the router or switch receives ping responses from the device, it considers the device to be reachable. After the router or switch has not received a reply to a set number of ICMP Echo Requests, it considers the device to be unreachable. It continues to try to ping the device, at an increased rate. After it receives a set number of responses, it considers the device to be reachable again.
Configuring the router or switch to determine a device’s reachability and respond to changes in reachability involves the following steps:
■Create a polling instance, to periodically ping the device
■Create scripts to run when the device becomes unreachable and when it becomes reachable again
■Configure triggers to run these scripts.
Patch