Configuring Port Security - Cisco 500 series Administration Manual

Stackable managed switch
Hide thumbs Also See for 500 series:
Table of Contents

Advertisement

Configuring Security

Configuring Port Security

Configuring Port Security
Cisco 500 Series Stackable Managed Switch Administration Guide
Network security can be increased by limiting access on a port to users with
specific MAC addresses. The MAC addresses can be either dynamically learned
or statically configured.
Port security monitors received and learned packets. Access to locked ports is
limited to users with specific MAC addresses.
Port Security has four modes:
Classic Lock—All learned MAC addresses on the port are locked, and the
port does not learn any new MAC addresses. The learned addresses are
not subject to aging or re-learning.
Limited Dynamic Lock—The switch learns MAC addresses up to the
configured limit of allowed addresses. After the limit is reached, the switch
does not learn additional addresses. In this mode, the addresses are
subject to aging and re-learning.
Secure Permanent—Keeps the current dynamic MAC addresses
associated with the port and learns up to the maximum number of
addresses allowed on the port (set by Max No. of Addresses Allowed).
Relearning and aging are enabled.
Secure Delete on Reset—Deletes the current dynamic MAC addresses
associated with the port after reset. New MAC addresses can be learned
as Delete-On-Reset ones up to the maximum addresses allowed on the
port. Relearning and aging are disabled.
When a frame from a new MAC address is detected on a port where it is not
authorized (the port is classically locked, and there is a new MAC address, or the
port is dynamically locked, and the maximum number of allowed addresses has
been exceeded), the protection mechanism is invoked, and one of the following
actions can take place:
Frame is discarded
Frame is forwarded
Port is shut down
When the secure MAC address is seen on another port, the frame is forwarded,
but the MAC address is not learned on that port.
In addition to one of these actions, you can also generate traps, and limit their
frequency and number to avoid overloading the devices.
18
318

Advertisement

Table of Contents
loading

Table of Contents