Understanding Port Security; Secure Mac Addresses - Cisco Catalyst 3750 Software Configuration Manual

Chapter 18 Configuring Port-Based Traffic Control
These sections include port security configuration information and procedures:
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Understanding Port Security

This section contains information about these topics:
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Secure MAC Addresses

You configure the maximum number of secure addresses allowed on a port by using the switchport
port-security maximum value interface configuration command.
Note If you try to set the maximum value to a number less than the number of secure addresses already
configured on an interface, the command is rejected.
The switch supports these types of secure MAC addresses:
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You can configure an interface to convert the dynamic MAC addresses to sticky secure MAC addresses
and to add them to the running configuration by enabling sticky learning. To enable sticky learning, enter
the switchport port-security mac-address sticky interface configuration command. When you enter
this command, the interface converts all the dynamic secure MAC addresses, including those that were
dynamically learned before sticky learning was enabled, to sticky secure MAC addresses. All sticky
secure MAC addresses are added to the running configuration.
The sticky secure MAC addresses do not automatically become part of the configuration file, which is
the startup configuration used each time the switch restarts. If you save the sticky secure MAC addresses
in the configuration file, when the switch restarts, the interface does not need to relearn these addresses.
If you do not save the sticky secure addresses, they are lost.
If sticky learning is disabled, the sticky secure MAC addresses are converted to dynamic secure
addresses and are removed from the running configuration.
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Understanding Port Security, page 18-7
Default Port Security Configuration, page 18-9
Configuration Guidelines, page 18-9
Enabling and Configuring Port Security, page 18-10
Enabling and Configuring Port Security Aging, page 18-13
Secure MAC Addresses, page 18-7
Security Violations, page 18-8
Static secure MAC addresses—These are manually configured by using the switchport
port-security mac-address mac-address interface configuration command, stored in the address
table, and added to the switch running configuration.
Dynamic secure MAC addresses—These are dynamically configured, stored only in the address
table, and removed when the switch restarts.
Sticky secure MAC addresses—These can be dynamically learned or manually configured, stored in
the address table, and added to the running configuration. If these addresses are saved in the
configuration file, when the switch restarts, the interface does not need to dynamically reconfigure
them.
Catalyst 3750 Metro Switch Software Configuration Guide
Configuring Port Security
18-7