Enabling Port Security; Defining The Maximum Secure Address Count - Cisco WS-C2955T-12 Software Manual

Enabling Port Security

Enabling Port Security
Secured ports restrict a port to a user-defined group of stations. When you assign secure addresses to a
secure port, the switch does not forward any packets with source addresses outside the group of
addresses you have defined. If you define the address table of a secure port to contain only one address,
the workstation or server attached to that port is guaranteed the full bandwidth of the port. As part of
securing the port, you can also define the size of the address table for the port.
Secured ports generate address-security violations under these conditions:
•
•
Limiting the number of devices that can connect to a secure port has these advantages:
•
•
These options validate port security or indicate security violations:
Interface
Security
Trap
Shutdown Port
Secure Addresses
Max Addresses
Security Rejects
For the restrictions that apply to secure ports, see the
page

Defining the Maximum Secure Address Count

A secure port can have from 1 to 132 associated secure addresses. Setting one address in the MAC
address table for the port ensures that the attached device has the full bandwidth of the port.
Enabling Port Security
Beginning in privileged EXEC mode, follow these steps to enable port security:
Command
Step 1 configure terminal
Step 2
interface interface
Catalyst 2900 Series XL and Catalyst 3500 Series XL Software Configuration Guide
7-10
The address table of a secured port is full and the address of an incoming packet is not found in the
table.
An incoming packet has a source address assigned as a secure address on another port.
Dedicated bandwidth—If the size of the address table is set to 1, the attached device is guaranteed
the full bandwidth of the port.
Added security—Unknown devices cannot connect to the port.
Port to secure.
Enable port security on the port.
Issue a trap when an address-security violation occurs.
Disable the port when an address-security violation occurs.
Number of addresses in the address table for this port. Secure ports have at
least one address.
Number of addresses that the address table for the port can contain.
The number of unauthorized addresses seen on the port.
9-7.
Purpose
Enter global configuration mode.
Enter interface configuration mode for the port you want to secure.
Chapter 7 Configuring the Switch Ports
"Avoiding Configuration Conflicts" section on
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