Configuring Authentication AAA | Enterasys Networks XSR-3150

VPN Sample Configuration with Network Extension Mode

Configuring Authentication (AAA)

Configure an AAA user and DEFAULT AAA group for remote users. When an ANG tunnels into the XSR, it will be assigned dynamically to the IP pool AUTH. Be aware that groups must be created before users can be added to them. Remember to create the same users and passwords on the ANG. The IP address assigned to the AAA user is the remote gatewayIP address.

XSR(config)#ip local pool AUTH 192.168.2.0 255.255.255.0

XSR(config)#aaa user 112.16.244.9

XSR(aaa-user)#password dribble

XSR(aaa-user)#group DEFAULT

XSR(aaa-group)#pptp encrypt mppe auto

XSR(aaa-group)#ip pool AUTH

XSR(aaa-group)#policy vpn

VPN Sample Configuration with Network Extension Mode

The following sample topology is ideal for testing a VPN NEM tunnel connection on a LAN before actually configuring a production network. If the configuration works properly, simply change the GigabitEthernet settings to the Serial or T1 interface values of your choice.

The XSR below is configured as a VPN concentrator with Internet access allowed and Network Extension Mode (NEM) tunnels set up. NEM is designed to open up network resources situated behind the XSR. You configure NEM to provide routing for nodes connected to the trusted port of the router so that locally and remotely connected devices can discover and communicate with each other across an IKE/IPSec tunnel.

The XSR’s EZ-IPSec functionality is employed to automatically access default ESP transforms and IPSec proposals.

Figure 3-6 VPN Topology with NEM, EZ-IPSec and Internet Access

	GigabitEthernet 1: 172.16.10/24	eth0: 10.11.11.1/24
	GigabitEthernet 2: 26.26.26.10/24	eth1: 26.26.26.11/24
	Virtual IP Pool: 172.16.10.0/24
	26.26.26.0/24	XSR
	26.26.26.0/24	eth0: 10.12.12.1/24
		eth0: 10.12.12.1/24
	XSR	eth1: 26.26.26.12/24
	XSR
	172.16.10.0	XSR
		XSR

The following script configures the VPN topology shown in Figure 3-6.

If you have not already generated a master encryption key, you must do so now to configure the VPN. A master key need only be generated once.

Caution: The master encryption key is stored in hardware, not Flash, and you cannot read the key - only overwrite the old key by writing a new one. To ensure router security, it is critical not to compromise the key. There are situations where you may want to keep the key, for example, to save the user database off-line in order to later download it to the XSR. In order to encrypt the user database, you need the same master key, indicating the key designation with the master key specify command. Be aware that if the XSR is inoperable you may have to return to factory defaults, which erases the master key forcing you to generate a new one.

3-30 Software Configuration