Allied Telesis AT-8550 - Manual (Page 56)

Enabling and Disabling Ports
3-2
Enabling and Disabling Ports
By default, all ports are enabled. To enable or disable one or more
ports, use the following command:
[enable | disable] port <portlist>
For example, to disable ports 3, 5, and 12 through 15 , enter the
following:
disable port 3,5,12-15
Even though a port is disabled, the link remains enabled for
diagnostic purposes.