Cisco ASA 5540

8-18
Cisco ASA 5500 Series Configuration Guide using ASDM
OL-20339-01
Chapter 8 Configuring Interfaces
Starting Interface Configuration (ASA 5505)
If you already have two VLAN interfaces configured with a name, be sure to configure this setting before
setting the name on the third interface; the adaptive security appliance does not allow three fully
functioning VLAN interfaces with the Base license on the ASA 5505 adaptive security appliance.
Note If you upgrade to the Security Plus license, you can remove this option and achieve full
functionality for this interface. If you leave this option enabled, this interface continues to be
limited even after upgrading.
To configure the MAC address and MTU, see the “Configuring Advanced Interface Parameters”
section on page 8-26.
Step 7 Click OK.
What to Do Next
Configure the switch ports. See the “Configuring and Enabling Switch Ports as Access Ports” section on
page 8-18 and the “Configuring and Enabling Switch Ports as Trunk Ports” section on page 8-19.
Configuring and Enabling Switch Ports as Access Ports
By default (with no configuration), all switch ports are shut down, and assigned to VLAN 1. To assign
a switch port to a single VLAN, configure it as an access port. To create a trunk port to carry multiple
VLANs, see the “Configuring and Enabling Switch Ports as Trunk Ports” section on page 8-19. If you
have a factory default configuration, see the “ASA 5505 Default Configuration” section on page 2-6 to
check if you want to change the default interface settings according to this procedure.
For more information about ASA 5505 interfaces, see the “ASA 5505 Interfaces” section on page 8-2.
Caution The ASA 5505 adaptive security appliance does not support Spanning Tree Protocol for loop detection
in the network. Therefore you must ensure that any connection with the adaptive security appliance does
not end up in a network loop.
Detailed Steps
Step 1 Choose the Configuration > Device Setup > Interfaces pane.
Step 2 Click the Switch Ports tab.
Step 3 Click the switch port you want to edit.
The Edit Switch Port dialog box appears.
Step 4 To enable the switch port, check the Enable SwitchPort check box.
Step 5 In the Mode and VLAN IDs area, click the Access radio button.
Step 6 In the VLAN ID field, enter the VLAN ID associated with this switch port. The VLAN ID can be
between 1 and 4090.