Configuring and Monitoring Port Security

Port Security Command Options and Operation

If you are adding a device (MAC address) to a port on which the Authorized Addresses list is already full (as controlled by the port’s current Address Limit setting), then you must increase the Address Limit in order to add the device, even if you want to replace one device with another. Using the CLI, you can simultaneously increase the limit and add the MAC address with a single command. For example, suppose port A1 allows one authorized device and already has a device listed:

 

Figure 9-6. Example of Port Security on Port A1 with an Address Limit of “1”

 

To add a second authorized device to port A1, execute a port-securitycommand

 

for port A1 that raises the address limit to 2 and specifies the additional

 

device’s MAC address. For example:

 

ProCurve(config)# port-security a1 mac-address 0c0090-

 

456456 address-limit 2

 

Removing a Device From the “Authorized” List for a Port Configured

 

for Learn-Mode Static. This command option removes unwanted devices

 

(MAC addresses) from the Authorized Addresses list. (An Authorized Address

 

list is available for each port for which Learn Mode is currently set to “Static”.

 

See the “MAC Address” entry in the table on 9-8.)

 

 

Caution

The address-limitsetting controls how many MAC addresses are allowed in

 

the Authorized Addresses list for a given port. If you remove a MAC address

 

without also reducing the address limit by 1, the port may later detect and

 

accept the same or another MAC address that you do not want in the Autho-

 

rized Address list. Thus, if you use the CLI to remove a MAC address that is

 

no longer authorized, you should first reduce the Address Limit (address-limit)

 

integer by 1, as shown in the next example. This prevents the possibility of the

 

same device or another device on the network from automatically being

 

accepted as “authorized” for that port. (You can prevent the port from learning

 

unauthorized MAC addresses by using the learn-mode configured option

 

instead of the learn-mode static option. Refer to the Note on page 9-8.)

 

 

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