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What is a port security violation?

What is a port security violation?

If the maximum number of secure MAC addresses has been reached, a security violation occurs when a devices with a different MAC addresses tries to attach to that port. In most of today’s scenarios when the switch detects a security violation, the switch automatically shuts down that port.

In which circumstances does a port security violation occur?

A security violation occurs if the maximum number of secure MAC addresses have been added to the address table and the port receives traffic from a MAC address that is not in the address table. You can configure the port for one of three violation modes: protect, restrict, or shutdown.

What can port security do?

Port Security helps secure the network by preventing unknown devices from forwarding packets. Packets that have a matching MAC address (secure packets) are forwarded; all other packets (unsecure packets) are restricted. You can enable port security on a per port basis.

What is the default port-security violation mode?

Switchport Violations These are described in more detail below: Shutdown – When a violation occurs in this mode, the switchport will be taken out of service and placed in the err-disabled state. The switchport will remain in this state until manually removed; this is the default switchport security violation mode.

What are the port-security violation modes?

Three possible modes are available:

  • Protect: – This mode will only work with sticky option.
  • Restrict: – In restrict mode frames from non-allowed address would be dropped.
  • Shutdown: – In this mode switch will generate the violation alert and disable the port.
  • Switch(config)# errdisable recovery cause psecure-violation.

What is the benefit of port security )?

Port Security Benefits Allows for limiting the number of MAC addresses on a given port. Packets that have a matching MAC address (secure packets) are forwarded; all other packets (unsecure packets) are restricted. Enabled on a per port basis. When locked, only packets with allowable MAC address will be forwarded.

When to use switchport port-security violation command?

Switchport Port-Security Violation Use Sets the action that occurs to the switch port when a violation is triggered. The violation types are: Protect: Ignores all traffic on the interface Restrict: Ignores all traffic on the interface, but

What happens when an interface is shut down by port security?

Once a Port Security violation happened, the interface is shut down and it is in a state called as Errdisable state. Use any of the following methods to bring the interface up after a Port Security violation related shutdown.

What is the violation mode for Cisco port security?

Table 1. Security Violation Mode Actions Violation Mode Traffic is forwarded 1 Sends SNMP trap Sends syslog message Displays error message 2 protect No No No No restrict No Yes Yes No shutdown No No No No shutdown vlan No No Yes No

How to enable port security violation in SW3?

Shutdown (default): Shuts the port down and does not allow device to connect. For this example, the port-security violation type is set to restrict on int fa0/2 on SW3. SW3#conf t Enter configuration commands, one per line.

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