11-37
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 11 Configuring IEEE 802.1x Port-Based Authentication Configuring 802.1x Authentication
–
EtherChannel port—Do not configure a port that is an active or a not-yet-active member of an
EtherChannel as an 802.1x port. If you try to enable 802.1x authentication on an EtherChannel
port, an error message appears, and 802.1x authentication is not enabled.
–
Switched Port Analyzer (SPAN) and Remote SPAN (RSPAN) destination ports—You can
enable 802.1x authentication on a port that is a SPAN or RSPAN destination port. However,
802.1x authentication is disabled until the port is removed as a SPAN or RSPAN destination
port. You can enable 802.1x authentication on a SPAN or RSPAN source port.
• Before globally enabling 802.1x authentication on a switch by entering the dot1x
system-auth-control global configuration command, remove the EtherChannel configuration from
the interfaces on which 802.1x authentication and EtherChannel are configured.
• If you are using a device running the Cisco Access Control Server (ACS) application for
IEEE 802.1x authentication with EAP-Transparent LAN Services (TLS) and EAP-MD5, make sure
that the device is running ACS Version 3.2.1 or later.
• When IP phones are connected to an 802.1x-enabled switch port that is in single host mode, the
switch grants the phones network access without authenticating them. We recommend that you use
multidomain authentication (MDA) on the port to authenticate both a data device and a voice device,
such as an IP phone.
Note Only Catalyst 3750, 3560, and 2960 switches support CDP bypass. The Catalyst 3750-X,
3560-X, 3750-E, and 3560-E switches do not support CDP bypass.
VLAN Assignment, Guest VLAN, Restricted VLAN, and Inaccessible Authentication Bypass
These are the configuration guidelines for VLAN assignment, guest VLAN, restricted VLAN, and
inaccessible authentication bypass:
• When 802.1x authentication is enabled on a port, you cannot configure a port VLAN that is equal
to a voice VLAN.
• The 802.1x authentication with VLAN assignment feature is not supported on trunk ports, dynamic
ports, or with dynamic-access port assignment through a VMPS.
• You can configure 802.1x authentication on a private-VLAN port, but do not configure IEEE 802.1x
authentication with port security, a voice VLAN, a guest VLAN, a restricted VLAN, or a per-user
ACL on private-VLAN ports.
• You can configure any VLAN except an RSPAN VLAN, private VLAN, or a voice VLAN as an
802.1x guest VLAN. The guest VLAN feature is not supported on internal VLANs (routed ports) or
trunk ports; it is supported only on access ports.
• After you configure a guest VLAN for an 802.1x port to which a DHCP client is connected, you
might need to get a host IP address from a DHCP server. You can change the settings for restarting
the 802.1x authentication process on the switch before the DHCP process on the client times out and
tries to get a host IP address from the DHCP server. Decrease the settings for the 802.1x
authentication process (authentication timer inactivity or dot1x timeout quiet-period and
authentication timer reauthentication or dot1x timeout tx-period). The amount to decrease the
settings depends on the connected 802.1x client type.
• When configuring the inaccessible authentication bypass feature, follow these guidelines:
–
The feature is supported on 802.1x port in single-host mode and multihosts mode.
–
If the client is running Windows XP and the port to which the client is connected is in the
critical-authentication state, Windows XP might report that the interface is not authenticated.