Users Guide

Critical VLAN: Disable
Critical VLAN id: NONE
Mac-Auth-Bypass: Disable
Mac-Auth-Bypass Only: Disable
Static-MAB: Disable
Static-MAB Profile: NONE
Tx Period: 30 seconds
Quiet Period: 60 seconds
ReAuth Max: 2
Supplicant Timeout: 30 seconds
Server Timeout: 30 seconds
Re-Auth Interval: 3600 seconds
Max-EAP-Req: 2
Host Mode: MULTI_AUTH
Max-Supplicants: 128
Port status and State info for Supplicant: 7a:d9:d9:7d:00:00
Port Auth Status: AUTHORIZED
Untagged VLAN id: 400
Auth PAE State: Authenticated
Backend State: Idle
Port status and State info for Supplicant: 7a:d9:d9:7d:00:01
Port Auth Status: AUTHORIZED
Untagged VLAN id: 400
Auth PAE State: Authenticated
Backend State: Idle
Restricting Multi-Supplicant Authentication
To restrict the number of devices that 802.1X can authenticate on a port in multi-supplicant (multi-auth) mode, enter the dot1x max-
supplicants number command in Interface mode. By default, the maximum number of multi-supplicant devices is 128.
Dell(conf-if-te-2/1)# dot1x max-supplicants 4
MAC Authentication Bypass
MAC authentication bypass (MAB) enables you to provide MAC-based security by allowing only known MAC addresses within the network
using a RADIUS server.
802.1X-enabled clients can authenticate themselves using the 802.1X protocol. Other devices that do not use 802.1X — like IP phones,
printers, and IP fax machines — still need connectivity to the network. The guest VLAN provides one way to access the network.
However, placing trusted devices on the quarantined VLAN is not the best practice. MAB allows devices that have known static MAC
addresses to be authenticated using their MAC address, and places them into a VLAN dierent from the VLAN in which unknown devices
are placed.
For an 802.1X-incapable device, 802.1X times out if the device does not respond to the Request Identity frame. If MAB is enabled, the port
is then put into learning state and waits indenitely until the device sends a packet. Once its MAC is learned, it is sent for authentication to
the RADIUS server (as both the username and password, in hexadecimal format without any colons). If the server authenticates
successfully, the port is dynamically assigned to a MAB VLAN using a RADIUS attribute 81, or is assigned to the untagged VLAN of the
port. Afterward, packets from any other MAC address are dropped. If authentication fails, the authenticator waits the quiet-period and then
restarts the authentication process.
MAC authentication bypass works in conjunction and in competition with the guest VLAN and authentication-fail VLAN. When both
features are enabled:
1 If authentication fails, the port it is placed into the authentication-fail VLAN.
2 If the host does not respond to the Request Identity frame, the port transitions to MAB initiation state.
802.1X
99