Tripp Lite NGI-M08C4POE8-2 Owner's Manual page 263

7.4 Port Security
The Switch will learn the MAC address of the device directly connected to a particular port and
allow traffic through. We will ask the question: "How do we control who and how many can
connect to a switch port?" This is where port security can assist us. The Switch allow us to control
which devices can connect to a switch port or how many of them can connect to it (such as when
a hub or another switch is connected to the port).
Let's say we have only one switch port left free and we need to connect five hosts to it. What can
we do? Connect a hub or switch to the free port! Connecting a switch or a hub to a port has
implications. It means that the network will have more traffic. If a switch or a hub is connected
by a user instead of an administrator, then there are chances that loops will be created. So, it is
best that number of hosts allowed to connect is restricted at the switch level. This can be done
using the "port-security limit" command. This command configures the maximum number of
MAC addresses that can source traffic through a port.
Port security can sets maximum number of MAC addresses allowed per interface. When the limit
is exceeded, incoming packets with new MAC addresses are dropped. It can be use MAC table
to check it. The static MAC addresses are included for the limit.
Note: If you configure a port of the Switch from disabled to enabled, all of the MAC learned by
this port will be clear.
7.4.1 Port Security
7.4.1.1 CLI Configurations
Node Command
enable show port-security
enable configure terminal
configure port-security
(disable|enable)
configure interface IFNAME
interface port-security
(disable|enable)
interface port-security limit
<1-1000>
configure interface range
gigabitethernet1/0/
PORTLISTS
if-range port-security
(disable|enable)
if-range port-security limit
<1-1000>
Description
This command displays the current port security
configurations.
This command changes the node to configure node.
This command enables / disables the global port
security function.
This command enters the interface configure node.
This command enables / disables the port security
function on the specific port.
This command configures the maximum MAC
entries on the specific port.
This command enters the if-range configure node.
This command enables / disables the port security
function for the specified ports
This command configures the maximum MAC
entries for the specified ports.
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