Access Control Lists

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Web – Click Security, Port Security. Set the action to take when an invalid address is
detected on a port, mark the checkbox in the Status column to enable security for a
port, set the maximum number of MAC addresses allowed on a port, and click Apply.
Figure 3-55 Configuring Port Security
CLI – This example selects the target port, sets the port security action to send a
trap and disable the port and sets the maximum MAC addresses allowed on the
port, and then enables port security for the port.

Access Control Lists

Access Control Lists (ACL) provide packet filtering for IP frames (based on address,
protocol, Layer 4 protocol port number or TCP control code) or any frames (based
on MAC address or Ethernet type). To filter incoming packets, first create an access
list, add the required rules, and then bind the list to a specific port.

Configuring Access Control Lists

An ACL is a sequential list of permit or deny conditions that apply to IP addresses,
MAC addresses, or other more specific criteria. This switch tests ingress or egress
packets against the conditions in an ACL one by one. A packet will be accepted as
soon as it matches a permit rule, or dropped as soon as it matches a deny rule. If no
rules match for a list of all permit rules, the packet is dropped; and if no rules match
for a list of all deny rules, the packet is accepted.
Command Usage
The following restrictions apply to ACLs:
Each ACL can have up to 100 rules.
However, due to resource restrictions, the average number of rules bound to the
ports should not exceed 20.
Console(config)#interface ethernet 1/5
Console(config-if)#port security action trap-and-shutdown 4-124
Console(config-if)#port security max-mac-count 20 4-124
Console(config-if)#port security 4-124
Console(config-if)#