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Catalyst2950 and Catalyst2955 Switch Software Configuration Guide
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Chapter10 Configuring 802.1x Port -Based Authentication Configuring 802.1x Authentication
To return to the default retransmission number, use the no dot1x max-req interface configuration
command.
This example shows how to set 5 as the number of times that the switch sends an EAP-request/identity
request before restarting the authentica tio n p r oce ss :
Switch(config-if)# dot1x max-req 5
Configuring the Host Mode
You can configure an 802.1x port for single-host or for multiple-hosts mode. In single-host mode, only
one host is allowed on an 802.1x port. When the host is authenticated, the port is placed in the authorized
state. When the host leaves the port, the port becomes unauthorized. Packets from hosts other than the
authenticated one are dropped.
You can attach multiple hosts to a single 802.1x-enabled port as shown in Figure 10-3 on page10-6. In
this mode, only one of the attached hosts must be successfully authorized for all hosts to be granted
network access. If the port becomes unauthorized (re-authenticati on fails or an EAPOL-logoff message
is received), all attached clients are denied access to the network.
With the multiple-hosts mode enabled, you can use 802.1x to authenticate the port and port security to
manage network access for all MAC addresses, including that of the client (for swit ches running the EI).
Beginning in privileged EXEC mode, follow these steps to allow multiple hosts (clients) on an
802.1x-authorized port that has the dot1x port-control interface configuration command set to auto.
This procedure is optional.
To disable multiple hosts on the port, use the no dot1x host-mode multi-host interface configuration
command.
This example shows how to enable a port to allow multiple hosts:
Switch(config)# interface fastethernet0/1
Switch(config-if)# dot1x port-control auto
Switch(config-if)# dot1x host-mode multi-host
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Specify the interface to which multiple hosts are indirectly attached, and
enter interface configuration mode.
Step3 dot1x host-mode multi-host Allow multiple hosts (clients) on an 802.1x-authorized port.
Make sure that the dot1x port-control interface configuration command
set is set to auto for the specified interface.
Step4 end Return to privileged EXEC mode.
Step5 show dot1x interface interface-id Verify your entries.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.