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Chapter 17 Port Security
XS3900-48F User’s Guide
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The following table describes the labels in this screen.
Table 52
Advanced Application > Port Security
LABEL
DESCRIPTION
Port List
Enter the number of the port(s) (separated by a comma) on which you want to enable port
security and disable MAC address learning. After you click MAC freeze, all previously
learned MAC addresses on the specified port(s) will become static MAC addresses and
display in the Static MAC Forwarding screen.
MAC freeze
Click MAC freeze to have the Switch automatically select the Active check boxes and clear
the Address Learning check boxes only for the ports specified in the Port list.
Active
Select this option to enable port security on the Switch.
Port
This field displays a port number.
*
Settings in this row apply to all ports.
Use this row only if you want to make some of the settings the same for all ports. Use this
row first to set the common settings and then make adjustments on a port-by-port basis.
Note: Changes in this row are copied to all the ports as soon as you make them.
Active
Select this check box to enable the port security feature on this port. The Switch forwards
packets whose MAC address(es) is in the MAC address table on this port. Packets with no
matching MAC address(es) are dropped.
Clear this check box to disable the port security feature. The Switch forwards all packets on
this port.
Address
Learning
MAC address learning reduces outgoing broadcast traffic. For MAC address learning to occur
on a port, the port itself must be active with address learning enabled.
Limited Number
of Learned MAC
Address
Use this field to limit the number of (dynamic) MAC addresses that may be learned on a
port. For example, if you set this field to "5" on port 2, then only the devices with these five
learned MAC addresses may access port 2 at any one time. A sixth device must wait until
one of the five learned MAC addresses ages out. MAC address aging out time can be set in
the Switch Setup screen. The valid range is from “0” to “16384”. “0” means this feature is
disabled.
Apply
Click Apply to save your changes to the Switch’s run-time memory. The Switch loses these
changes if it is turned off or loses power, so use the Save link on the top navigation panel to
save your changes to the non-volatile memory when you are done configuring.
Cancel
Click Cancel to begin configuring this screen afresh.