All Cisco ASA firewall models from 5510 and higher, include an extra ethernet interface for management. By default, this specific interface is set to management-only mode, which means that it can receive traffic only, but it does not allow traffic to pass through to other interfaces.

In order to enable the Management 0/0 interface to act as a normal Firewall interface, use the following configuration:

asa (config)# interface management 0/0
asa (config-if)# no management-only

With the above, you just added one more normal firewall interface to your appliance since the management interface can now pass through traffic just like any other interface.

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