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Release Information
Statement introduced in Junos OS Release 9.0 for EX Series switches.

Description
Specify the number of MAC addresses to dynamically add to the MAC address cache for this access interface (port) and the action to be taken by the switch if the MAC address learning limit is exceeded on the interface (port).

When you reset the number of MAC addresses, the MAC address table is not automatically cleared. Therefore, if you reduce the number of addresses from the default (unlimited) or a previously set limit, you could already have more entries in the table than the new limit allows. Previous entries remain in the table after you reduce the number of addresses, so you should clear the forwarding table for the specified interface or MAC address. Use the command clear ethernet-switching tableto clear the existing MAC addresses from the table.

Default
The default action is drop.

Options
action action—(Optional) Action to take when the MAC address limit is exceeded:

drop—Drop the packet and generate an alarm, an SNMP trap, or a system log entry. This is the default.
log—Do not drop the packet but generate an alarm, an SNMP trap, or a system log entry.
none—No action.
shutdown—Disable the interface and generate an alarm. If you have configured the switch with the port-error-disable statement, the disabled interface recovers automatically upon expiration of the specified disable timeout. If you have not configured the switch for autorecovery from port error disabled conditions, you can bring up the disabled interfaces by running the clear ethernet-switching port-error command.
limit—Maximum number of MAC addresses.

Required Privilege Level
system—To view this statement in the configuration.
system–control—To add this statement to the configuration.