Standalone MAB Support

Standalone MAC Authentication Bypass (MAB) is an authentication method that grants network access to specific MAC addresses regardless of 802.1X capability or credentials. As a result, devices such as cash registers, fax machines, and printers can be readily authenticated, and network features that are based on authorization policies can be made available.

Before standalone MAB support was available, MAB could be configured only as a failover method for 802.1x authentication. Standalone MAB is independent of 802.1x authentication.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.

Information About Configuring Standalone MAB

Standalone MAB

MAC Authentication Bypass (MAB) uses the MAC address of the connecting device to grant or deny network access. To support MAB, the RADIUS authentication server maintains a database of MAC addresses for devices that require access to the network. MAB generates a RADIUS request with a MAC address in the Calling-Station-Id (attribute 31) and with a Service-Type (attribute 6) 10. After a successful authentication, the Auth Manager enables various authorization features specified by the authorization policy, such as ACL assignment and VLAN assignment.

How to Configure Standalone MAB Support

Enabling Standalone MAB

Ports enabled with the Standalone MAB feature can use the MAC address of connecting devices to grant or deny network access. Perform the steps described in this section to enable standalone MAB on individual ports.

Before you begin

Before you can configure standalone MAB, the device must be connected to a Cisco Secure ACS server and RADIUS authentication, authorization, and accounting (AAA) must be configured.


Note

Standalone MAB can be configured on devices with switched ports only; it cannot be configured on devices with routed ports.


Note

If you are unsure whether MAB or MAB Extensible Authentication Protocol (EAP) is enabled or disabled on the switched port, use the default mab or default mab eap commands in interface configuration mode to configure MAB or MAB EAP.

SUMMARY STEPS

  1. enable
  2. configure terminal
  3. interface type slot / port
  4. switchport
  5. switchport mode access
  6. authentication port-control auto
  7. mab
  8. end

DETAILED STEPS

  Command or Action Purpose
Step 1

enable

Example:


Device> enable

Enables privileged EXEC mode.

  • Enter your password if prompted.

Step 2

configure terminal

Example:


Device# configure terminal

Enters global configuration mode.

Step 3

interface type slot / port

Example:


Device(config)# interface Gigabitethernet 1/2/1

Enters interface configuration mode.

Step 4

switchport

Example:


Switch(config-if)# switchport

Places interface in Layer 2 switched mode.

Step 5

switchport mode access

Example:


Device(config-if)# switchport mode access

Sets the interface type a as nontrunking, nontagged single VLAN Layer 2 interface.

Step 6

authentication port-control auto

Example:


Device(config-if)# authentication port-control auto

Configures the authorization state of the port.

Step 7

mab

Example:


Device(config-if)# mab

Enables MAB.

Step 8

end

Example:


Device(config-if)# end

Exits interface configuration mode and returns to privileged EXEC mode.

Troubleshooting Tips

The following commands can help troubleshoot standalone MAB:

  • debug authentication

  • debug mab all

  • show authentication registrations

  • show authentication sessions

  • show mab

Configuration Examples for Standalone MAB Support

Example: Standalone MAB Configuration

The following example shows how to configure standalone MAB on a port. In this example, the client is reauthenticated every 1200 seconds and the connection is dropped after 600 seconds of inactivity. 


Device> enable
Device# configure terminal
Device(config)# interface GigabitEthernet 1/2/1
Device(config-if)# switchport
Device(config-if)# switchport mode access
Device(config-if)# switchport access vlan 2
Device(config-if)# authentication port-control auto
Device(config-if)# mab
Device(config-if)# authentication violation shutdown 
Device(config-if)# authentication timer restart 30 
Device(config-if)# authentication periodic 
Device(config-if)# authentication timer reauthenticate 1200 
Device(config-if)# authentication timer inactivity 600

Additional References

Related Documents

Related Topic

Document Title

Cisco IOS commands

Cisco IOS Master Command List, All Releases

Authentication commands

Cisco IOS Security Command Reference

IEEE 802.1x—Flexible Authentication

Securing User Services Configuration Library

MIBs

MIB

MIBs Link

  • CISCO-AUTH-FRAMEWORK-MIB

  • CISCO-MAC-AUTH-BYPASS-MIB

  • CISCO-PAE-MIB

  • IEEE8021-PAE-MIB

To locate and download MIBs for selected platforms, Cisco IOS software releases, and feature sets, use Cisco MIB Locator found at the following URL:

http://www.cisco.com/go/mibs

RFCs

RFC

Title

RFC 3580

IEEE 802.1x Remote Authentication Dial In User Service (RADIUS)

Technical Assistance

Description

Link

The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

http://www.cisco.com/cisco/web/support/index.html

Feature Information for Standalone MAB Support

The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Table 1. Feature Information for Standalone MAB Support

Feature Name

Releases

Feature Information

Standalone MAB Support

12.2(33)SXI

15.2(2)T

This feature grants network access to devices based on MAC address regardless of 802.1x capability or credentials.

The following commands were introduced or modified: authentication periodic , authentication port-control , authentication timer inactivity , authentication timer reauthenticate , authentication timer restart , authentication violation , debug authentication , mab , show authentication interface , show authentication registrations , show authentication sessions , and show mab .