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Catalyst 3560 Switch Software Configuration Guide
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Chapter 20 Configuring Port-Based Traffic Control
Configuring Protected Ports
Configuring Protected Ports
Some applications require that no traffic be forwarded at Layer 2 between ports on the same switch so
that one neighbor does not see the traffic generated by another neighbor. In such an environment, the use
of protected ports ensures that there is no exchange of unicast, broadcast, or multicast traffic between
these ports on the switch.
Protected ports have these features:
•
A protected port does not forward any traffic (unicast, multicast, or broadcast) to any other port that
is also a protected port. Traffic cannot be forwarded between protected ports at Layer 2; all traffic
passing between protected ports must be forwarded through a Layer 3 device.
•
Forwarding behavior between a protected port and a nonprotected port proceeds as usual.
Default Protected Port Configuration
The default is to have no protected ports defined.
Protected Port Configuration Guidelines
You can configure protected ports on a physical interface (for example, Gigabit Ethernet port 1) or an
EtherChannel group (for example, port-channel 5). When you enable protected ports for a port channel,
it is enabled for all ports in the port-channel group.
Configuring a Protected Port
Beginning in privileged EXEC mode, follow these steps to define a port as a protected port:
To disable protected port, use the no switchport protected interface configuration command.
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
interface interface-id
Enter interface configuration mode, and enter the type and
number of the interface to configure, for example
gigabitethernet0/1.
Step 3
switchport protected
Configure the interface to be a protected port.
Step 4
end
Return to privileged EXEC mode.
Step 5
show interfaces interface-id switchport
Verify your entries.
Step 6
copy running-config startup-config
(Optional) Save your entries in the configuration file.
