Resuming Normal Forwarding On A Port - Cisco WS-C3550-12G Software Configuration Manual

Chapter 12 Configuring Port-Based Traffic Control
To return the interface to the default condition where no traffic is blocked, use the no switchport block
{multicast | unicast} interface configuration commands.
This example shows how to block unicast and multicast flooding on Gigabit Ethernet interface 0/1 and
verify the configuration:
Switch# configure terminal
Switch(config)# interface gigabitethernet0/1
Switch(config-if)# switchport block multicast
Switch(config-if)# switchport block unicast
Switch(config-if)# end
Switch# show interfaces gigabitethernet0/1 switchport
Name: Gi0/1
Switchport: Enabled
<output truncated>
Protected: True
Unknown unicast blocked: enabled
Unknown multicast blocked: enabled

Resuming Normal Forwarding on a Port

Beginning in privileged EXEC mode, follow these steps to resume normal forwarding on a port:
Command
Step 1 configure terminal
Step 2
interface interface-id
Step 3
no switchport block multicast
Step 4 no switchport block unicast
Step 5 end
Step 6
show interfaces interface-id switchport
Step 7 copy running-config startup-config
78-11194-03
Purpose
Enter global configuration mode.
Enter interface configuration mode and enter the type and number of the
switchport interface to configure, for example gigabitethernet0/1.
Enable unknown multicast flooding to the port.
Enable unknown unicast flooding to the port.
Return to privileged EXEC mode
Verify your entries.
(Optional) Save your entries in the configuration file.
Catalyst 3550 Multilayer Switch Software Configuration Guide
Configuring Port Blocking
12-7