Cisco Gigabit Ethernet Switch Module for HP p-Class BladeSystem Software Configuration Guide

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Cisco Gigabit Ethernet Switch Module for HP p-Class BladeSystem Software Configuration Guide
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Chapter 6 Configuring IEEE 802.1x Port-Based Authentication
Understanding IEEE 802.1x Port-Based Authentication
The maximum size of the per-user ACL is 4000 ASCII characters but is limited by the maximum size of
RADIUS-server per-user ACLs.
For examples of vendor-specific attributes, see the “Configuring the Switch to Use Vendor-Specific
RADIUS Attributes” section on page 5-29. For more information about configuring ACLs, see
Chapter 26, “Configuring Network Security with ACLs.”
To configure per-user ACLs, you need to perform these tasks:
• Enable AAA authentication.
• Enable AAA authorization by using the network keyword to allow interface configuration from the
RADIUS server.
• Enable IEEE 802.1x authentication.
• Configure the user profile and VSAs on the RADIUS server.
• Configure the IEEE 802.1x port for single-host mode.
Using IEEE 802.1x Authentication with Guest VLAN
You can configure a guest VLAN for each IEEE 802.1x port on the switch to provide limited services
to clients, such as downloading the IEEE 802.1x client. These clients might be upgrading their system
for IEEE 802.1x authentication, and some hosts, such as Windows 98 systems, might not be
IEEE 802.1x-capable.
When you enable a guest VLAN on an IEEE 802.1x port, the switch assigns clients to a guest VLAN
when the switch does not receive a response to its EAP request/identity frame or when EAPOL packets
are not sent by the client.
With Cisco IOS Release 12.2(25)SE1 and later, the switch maintains the EAPOL packet history. If an
EAPOL packet is detected on the interface during the lifetime of the link, the switch determines that the
device connected to that interface is an IEEE 802.1x-capable supplicant, and the interface does not
change to the guest VLAN state. EAPOL history is cleared if the interface link status goes down. If no
EAPOL packet is detected on the interface, the interface changes to the guest VLAN state.
Before Cisco IOS Release 12.2(25)SE1, the switch did not maintain the EAPOL packet history and
allowed clients that failed authentication access to the guest VLAN, regardless of whether EAPOL
packets had been detected on the interface. You can enable this behavior by using the dot1x guest-vlan
supplicant global configuration command. However, in Cisco IOS Release 12.2(25)SEE, the dot1x
guest-vlan supplicant global configuration command is no longer supported. Use a restricted VLAN to
allow clients that failed authentication access to the network by entering the dot1x auth-fail vlan vlan-id
interface configuration command.
In Cisco IOS Release 12.2(25)SEE and later, i no longer allows
Note If an EAPOL packet is detected after the interface has changed to the guest VLAN, the interface reverts
to an unauthorized state, and IEEE 802.1x authentication restarts.
Any number of IEEE 802.1x-incapable clients are allowed access when the switch port is moved to the
guest VLAN. If an IEEE 802.1x-capable client joins the same port on which the guest VLAN is
configured, the port is put into the unauthorized state in the user-configured access VLAN, and
authentication is restarted.