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Catalyst 2940 Switch Software Configuration Guide
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Chapter17 Configuring Port-Based Tra ffic Control Configuring Port Security
Default Port Security Configuration
Table17-2 shows the default port security configuration for an interface.
Port Security Configuration Guidelines
Follow these guidelines when configuring port security:
•Port security can only be configured on static access ports.
•A secure port cannot be a dynamic access port or a trunk port.
•A secure port cannot be a destination port for Switched Port Ana lyze r (SPAN).
•A secure port cannot be a destination port for Switched Port Ana lyze r (SPAN).
•A secure port cannot belong to a Fast EtherChannel or Gigabi t E the rChann el por t gr oup .
•You cannot configure static secure or sticky secure MAC addresses on a voice VLAN.
•When you enable port security on an interface that is also configured with a voice VLAN, you must
set the maximum allowed secure addresses on the port to at least two.
•The switch does not support port security aging of sticky secure MAC addresses.
•The protect and restrict options cannot be simultaneo usly enabled on an interfac e.
Enabling and Configuring Port Security
Beginning in privileged EXEC mode, follow these steps to restrict input to an interface by limiting and
identifying MAC addresses of the stations allowed to access the port:
Table17-2 Default Port Security Configuration
Feature Default Setting
Port security Disabled.
Maximum number of secure MAC addresses One.
Violation mode Shutdown.
Sticky address learning Disabled.
Port security aging Disabled. Aging time is 0. When enabled, the default
type is absolute.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Specify the type and number of the physical interface t o configur e, f or
example gigabitethernet0/1, and enter interface configuration mode.
Step3 switchport mode access Set the interface mode as access; an interface in the default mode
(dynamic desirable) cannot be configured as a secure port.
Step4 switchport port-security Enable port security on the interface.
Step5 switchport port-security maximum
value (Optional) Set the maximum number of secure MAC addresses for the
interface. The range is 1 to 132; the default is 1.