Configuring re-DHCP portal authentication

As shown in Figure 48:

• The host is directly connected to the switch and the switch is configured for re-DHCP authentication. The host is assigned with an IP address through the DHCP server. Before passing portal authentication, the host uses an assigned private IP address. After passing portal authentication, the host can get a public IP address and access Internet resources.

• A RADIUS server serves as the authentication/accounting server.

When you configure re-DHCP portal authentication, follow these guidelines:

• Configure a public address pool (20.20.20.0/24, in this example) and a private address pool (10.0.0.0/24, in this example) on the DHCP server. (Details not shown)

• The switch must be configured as a DHCP relay agent and the portal-enabled interface must be configured with a primary IP address (a public IP address) and a secondary IP address (a private IP address). For information about DHCP relay agent configuration, see Layer 3—IP Services Configuration Guide.

• Make sure the IP address of the portal device added on the portal server is the public IP address of the interface connecting users (20.20.20.1 in this example), the private IP address range for the IP address group associated with the portal device is the private network segment where the users reside (10.0.0.0/24 in this example), and the public IP address range for the IP address group is the public network segment 20.20.20.0/24.

• Configure IP addresses for the switch and servers as shown in Figure 48 and make sure that the host, switch, and servers can reach each other.

• Configure the RADIUS server properly to provide authentication and accounting functions for users.

Perform the following configuration to configure re-DHCP authentication on the switch:

# Create a RADIUS scheme named rs1 and enter its view.

<Switch> system-view
[Switch] radius scheme rs1

# Set the server type for the RADIUS scheme. When using the IMC server, set the server type to extended.

[Switch-radius-rs1] server-type extended

# Specify the primary authentication server and primary accounting server, and configure the keys for communication with the servers.

[Switch-radius-rs1] primary authentication 192.168.0.113
[Switch-radius-rs1] primary accounting 192.168.0.113
[Switch-radius-rs1] key authentication simple radius
[Switch-radius-rs1] key accounting simple radius

# Specify that the ISP domain name should not be included in the username sent to the RADIUS server.

[Switch-radius-rs1] user-name-format without-domain
[Switch-radius-rs1] quit

# Create an ISP domain named dm1 and enter its view.

[Switch] domain dm1

# Configure AAA methods for the ISP domain.

[Switch-isp-dm1] authentication portal radius-scheme rs1
[Switch-isp-dm1] authorization portal radius-scheme rs1
[Switch-isp-dm1] accounting portal radius-scheme rs1
[Switch-isp-dm1] quit

# Configure domain dm1 as the default ISP domain for all users. Then, if a user enters the username without the ISP domain at logon, the authentication and accounting methods of the default domain are used for the user.

[Switch] domain default enable dm1

# Configure the portal server as follows:

• Name: newpt

• IP address: 192.168.0.111

• Key: portal in plain text

• Port number: 50100

• URL: http://192.168.0.111:8080/portal

[Switch] portal server newpt ip 192.168.0.111 key simple portal port 50100 url http://192.168.0.111:8080/portal

# Configure the switch as a DHCP relay agent, and enable the IP address check function.

[Switch] dhcp enable
[Switch] dhcp relay server-group 0 ip 192.168.0.112
[Switch] interface vlan-interface 100
[Switch–Vlan-interface100] ip address 20.20.20.1 255.255.255.0
[Switch–Vlan-interface100] ip address 10.0.0.1 255.255.255.0 sub
[Switch-Vlan-interface100] dhcp select relay
[Switch-Vlan-interface100] dhcp relay server-select 0
[Switch-Vlan-interface100] dhcp relay address-check enable

# Enable re-DHCP portal authentication on the interface connecting the host.

[Switch–Vlan-interface100] portal server newpt method redhcp
[Switch–Vlan-interface100] quit