Example: Connecting a RADIUS Server for 802.1X to an EX Series Switch

 

802.1X is the IEEE standard for port-based network access control (PNAC). You use 802.1X to control network access. Only users and devices providing credentials that have been verified against a user database are allowed access to the network. You can use a RADIUS server as the user database for 802.1X authentication, as well as for MAC RADIUS authentication.

This example describes how to connect a RADIUS server to an EX Series switch, and configure it for 802.1X:

Requirements

This example uses the following software and hardware components:

  • Junos OS Release 9.0 or later for EX Series switches

  • One EX Series switch acting as an authenticator port access entity (PAE). The ports on the authenticator PAE form a control gate that blocks all traffic to and from supplicants until they are authenticated.

  • One RADIUS authentication server that supports 802.1X. The authentication server acts as the backend database and contains credential information for hosts (supplicants) that have permission to connect to the network.

Before you connect the server to the switch, be sure you have:

Overview and Topology

The EX Series switch acts as an authenticator PAE. It blocks all traffic and acts as a control gate until the supplicant (client) is authenticated by the server. All other users and devices are denied access.

Figure 1 shows one EX4200 switch that is connected to the devices listed in Table 1.

Figure 1: Topology for Configuration
Topology for Configuration

Table 1: Components of the Topology

PropertySettings

Switch hardware

EX4200 access switch, 24 Gigabit Ethernet ports: 8 PoE ports (ge-0/0/0 through ge-0/0/7) and 16 non-PoE ports (ge-0/0/8 through ge-0/0/23)

VLAN name

default

One RADIUS server

Backend database with an address 10.0.0.100 connected to the switch at port ge-0/0/10

In this example, connect the RADIUS server to access port ge-0/0/10 on the EX4200 switch. The switch acts as the authenticator and forwards credentials from the supplicant to the user database on the RADIUS server. You must configure connectivity between the EX4200 and the RADIUS server by specifying the address of the server and configuring the secret password. This information is configured in an access profile on the switch.

Note

For more information about authentication, authorization, and accounting (AAA) services, see the Junos OS System Basics Configuration Guide.

Configuration

CLI Quick Configuration

To quickly connect the RADIUS server to the switch, copy the following commands and paste them into the switch terminal window:

[edit]


set access radius-server 10.0.0.100 secret juniper
set access radius-server 10.0.0.200 secret juniper
set access profile profile1 authentication-order radius
set access profile profile1 radius authentication-server [10.0.0.100 10.0.0.200]

Step-by-Step Procedure

To connect the RADIUS server to the switch:

  1. Define the address of the servers, and configure the secret password. The secret password on the switch must match the secret password on the server:
    [edit]

    user@switch# set access radius-server 10.0.0.100 secret juniper
    user@switch# set access radius-server 10.0.0.200 secret juniper
  2. Configure the authentication order, making radius the first method of authentication:
    [edit]

    user@switch# set access profile profile1 authentication-order radius
  3. Configure a list of server IP addresses to be tried in sequential order to authenticate the supplicant:
    [edit]

    user@switch# set access profile profile1 radius authentication-server [10.0.0.100 10.0.0.200]

Results

Display the results of the configuration:

Verification

To confirm that the configuration is working properly, perform these tasks:

Verify That the Switch and RADIUS Server Are Properly Connected

Purpose

Verify that the RADIUS server is connected to the switch on the specified port.

Action

Ping the RADIUS server to verify the connection between the switch and the server:

user@switch> ping 10.0.0.100

Meaning

ICMP echo request packets are sent from the switch to the target server at 10.0.0.100 to test whether the server is reachable across the IP network. ICMP echo responses are being returned from the server, verifying that the switch and the server are connected.