Technical Documentation

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:


This example uses the following hardware and software components:

  • JUNOS 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 Port Access Entity (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

Image g020048.gif

Table 1: Components of the Topology

Property Settings

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


One RADIUS server

Backend database with an address of 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, please see the JUNOS Software System Basics Configuration Guide at


CLI Quick Configuration

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


set access radius-server secret juniper

set access profile profile1 authentication-order radius

set access profile profile1 radius authentication-server

Step-by-Step Procedure

To connect the RADIUS server to the switch:

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

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

    [edit access profile]
    user@switch# set profile1 authentication-order radius

  3. Configure a list of server IP addresses to be tried in order to authenticate the supplicant:

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


Display the results of the configuration:

user@switch> show configuration access
radius-server {
port 1812;
secret "$9$qPT3ApBSrv69rvWLVb.P5"; ## SECRET-DATA
profile profile1{
authentication-order radius;
radius {


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

Verify That the Switch and RADIUS Server are Properly Connected


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


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

user@switch> ping
PING ( 56 data bytes
64 bytes from icmp_seq=0 ttl=64 time=9.734 ms
64 bytes from icmp_seq=1 ttl=64 time=0.228 ms


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

Published: 2009-08-05