Configuring Port Security; Understanding Port Security; Secure Mac Addresses - Cisco WS-C3750-48PS-S Software Configuration Manual

Chapter 24 Configuring Port-Based Traffic Control
This example shows how to block unicast and multicast flooding on a port:
Switch# configure terminal
Switch(config)# interface gigabitethernet1/0/1
Switch(config-if)# switchport block multicast
Switch(config-if)# switchport block unicast
Switch(config-if)# end

Configuring Port Security

You can use the port security feature to restrict input to an interface by limiting and identifying MAC
addresses of the stations allowed to access the port. When you assign secure MAC addresses to a secure
port, the port does not forward packets with source addresses outside the group of defined addresses. If
you limit the number of secure MAC addresses to one and assign a single secure MAC address, the
workstation attached to that port is assured the full bandwidth of the port.
If a port is configured as a secure port and the maximum number of secure MAC addresses is reached,
when the MAC address of a station attempting to access the port is different from any of the identified
secure MAC addresses, a security violation occurs. Also, if a station with a secure MAC address
configured or learned on one secure port attempts to access another secure port, a violation is flagged.
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.
If you try to set the maximum value to a number less than the number of secure addresses already
Note
configured on an interface, the command is rejected.
78-16180-02
Understanding Port Security, page 24-7
Default Port Security Configuration, page 24-9
Configuration Guidelines, page 24-10
Enabling and Configuring Port Security, page 24-10
Enabling and Configuring Port Security Aging, page 24-14
Port Security and Switch Stacks, page 24-15
Secure MAC Addresses, page 24-7
Security Violations, page 24-8
Catalyst 3750 Switch Software Configuration Guide
Configuring Port Security
24-7