Source Addressing
NOTE |
Remember, you must have SuperUser (SU) access to the device in order to lock or unlock ports.
In addition to activating the security measures as configured via the Security application, locking source addresses has the following effects:
•On devices running older versions of firmware, unlinked ports will be disabled immediately after locking has been enabled; these ports can be re- enabled using their port menus, but they will immediately be disabled again if a device is connected and begins transmitting (since the port’s source address table was locked in an empty state). On devices with newer firmware, unlinked ports are not automatically disabled in response to port locking, but they, too, will be immediately disabled if a device is connected and attempts to transmit packets.
•Although the Source Ageing Interval does not apply to station ports when Source Address Locking is enabled, the snapshot of the SAT provided by the Source Address List window may show a learned source address ageing out if that address remains inactive, and the appropriate trap will be generated.
•Once Source Address Locking has been enabled, each port’s topology status (station or trunk) remains fixed and will not change while locking remains enabled, regardless of any changes in the number of source addresses detected.
•If Source Address Locking has been enabled, and one or more ports have been shut down because a new source address attempted access, those ports will remain disabled even after the SEHI has been reset, and must be
Source Address Locking on Older Devices
If your SEHI is running a firmware version previous to 1.05.01, Source Address Locking is implemented somewhat differently:
•Station ports are defined as those detecting zero or one source address; trunk ports as those detecting two or more.
•If a locked station port experiences a violation, the port will be automatically disabled and no traffic will be allowed through — not even traffic from the known source address.
•Trunk ports are never locked.
•Unlinked ports are immediately disabled.
•The Source Ageing Interval does not apply to locked station ports.
Locking Source Addresses |
