This section provides an example for configuring L2TP VPN in the client-initiated scenario. In the client-initiated scenario, the LNS works with the RADIUS server to perform identity authentication for mobile users.
Networking Requirements
On the enterprise network shown in
Figure 1, mobile users access intranet resources through L2TP VPN tunnels. The enterprise deploys a RADIUS server to perform identity authentication for the mobile users.
Figure 1 Networking where mobile users access intranet resources through L2TP VPN tunnels
Data Planning
Item
|
Data
|
LNS
|
Interface
|
Interface ID: GigabitEthernet 0/0/1
IP address: 1.1.1.1/24
Security zone: Untrust
Interface ID: GigabitEthernet 0/0/2
IP address: 10.1.1.1/24
Security zone: Trust
Interface ID: GigabitEthernet 0/0/3
IP address: 10.1.3.1/24
Security zone: DMZ
|
L2TP configuration
|
User name: user0001
Password: Password123
Peer tunnel name: client
Tunnel authentication password: Hello123
Address pool: 172.16.1.2 to 172.16.1.100
NOTE: If the intranet server IP address and address pool addresses are on different network segments, configure a route on the intranet server to an address in the address pool.
|
Parameters for interconnection with the RADIUS server
|
RADIUS server address: 10.1.3.2/24
Shard key: Radius123
|
Mobile user
|
User name: user0001
Password: Password123
Tunnel name: client
Tunnel authentication password: Hello123
|
Procedure
- Configure the LNS.
- Set IP addresses for interfaces and assign the interfaces to security zones.
- Choose Network > Interface.
Click
of GE0/0/1 and set required parameters.
Zone
|
untrust
|
IPv4
|
IP Address
|
1.1.1.1/24
|
- Click OK.
Repeat the preceding steps to configure GE0/0/2 and GE0/0/3.
Zone
|
trust
|
IPv4
|
IP Address
|
10.1.1.1/24
|
Zone
|
dmz
|
IPv4
|
IP Address
|
10.1.3.1/24
|
- Set parameters for interconnecting with the RADIUS server.
- Choose . Click Add to set parameters for interconnecting with the RADIUS server.

Click Test and then OK in the dialog box that is displayed. Then enter the account name and password obtained from the RADIUS server. Click Start to check the connectivity to the RADIUS server.
- Click OK.
- Configure the authentication domain.
Authentication domain default is used as an example. You can define an authentication domain.
- Choose Object > User > default and configure RADIUS server authentication.

- Click Apply.
- Configure L2TP VPN.
- Choose .
In Configure L2TP, select Enable and click Apply.
In L2TP Group List, click Add and set L2TP parameters.
Set Password to Hello123 and the address range of Address/Address Pool to 172.16.1.2 to 172.16.1.100. Associated Zone indicates the security zone where the VT interface resides. Server Address/Subnet Mask is the address of the VT interface on the LNS side. It is recommended that the IP address be in the same network as the address pool.

- Click OK.
- Configure a route to the Internet. It is assumed that the next-hop address of the route from the LNS to the Internet is 1.1.1.2.
- Choose .
Click Add and set required parameters.
Destination Address/Mask
|
0.0.0.0/0.0.0.0
|
Next Hop
|
1.1.1.2
|
Click OK.
- Configure a security policy.
Choose .
Click Add. Configure interzone security policies between the Trust zone and DMZ to permit the traffic sent by mobile users to access the intranet of the headquarters and the traffic sent by devices on the intranet of the headquarters to mobile users. After the configuration is complete, click OK.
Name
|
service_td
|
Source Zone
|
trust
|
Destination Zone
|
dmz
|
Source Address/Region
|
10.1.2.0/24
|
Destination Address/Region
|
172.16.1.0/24
|
Action
|
Permit
|
Name
|
service_dt
|
Source Zone
|
dmz
|
Destination Zone
|
trust
|
Source Address/Region
|
172.16.1.0/24
|
Destination Address/Region
|
10.1.2.0/24
|
Action
|
Permit
|
Click Add. Configure an interzone security policy from the Untrust zone to the Local zone to permit L2TP packets. After the configuration is complete, click OK.
In this scenario, the LNS only receives L2TP negotiation packets and does not proactively send L2TP negotiation packets to mobile users. Therefore, only the interzone security policy from the Untrust zone to the Local zone needs to be configured.
Name
|
l2tp_ul
|
Source Zone
|
untrust
|
Destination Zone
|
local
|
Destination Address/Region
|
1.1.1.0/24
|
Action
|
Permit
|
- Configure an interzone security policy from the DMZ to the Local zone to permit packets exchanged between the LNS and LDAP server.
Name
|
radius_ld
|
Source Zone
|
local
|
Destination Zone
|
dmz
|
Source Address/Region
|
10.1.3.0/24
|
Action
|
Permit
|
- Configure a RADIUS server. For how to configure a RADIUS server, see the documents of the RADIUS server.
- Configure the SecoClient at the mobile user side.
- Open the SecoClient and access the home page.
Select New Connection from the Connect drop-down list.

- Set L2TP VPN connection parameters.
In the New Connection navigation tree, select L2TP/IPSec. Set connection parameters and click OK.
The tunnel authentication password is Hello123.

- Log in to the L2TP VPN gateway.
- Select the created L2TP VPN connection from the Connect drop-down list and click Connect.

- On the login page, enter the user name and password.

- Click Login to initiate a VPN connection request.
A message on a VPN access success will be displayed on the web UI. After the connection is established, mobile users can access intranet resources as intranet users.

Verification
- Log in to the LNS and choose to view the monitoring list. You can find that user user0001 has logged in to the device successfully.
- Mobile users can access intranet resources properly.
Configuration Scripts
#
sysname LNS
#
l2tp enable
undo l2tp sendaccm enable
l2tp domain suffix-separator @
#
radius-server template radius
radius-server shared-key cipher %^%#:1t2V{T>#;^e6c2&x1R-s-r<"r6^,+]@!s#jY;T%%^%#
radius-server authentication 10.1.3.2 1645 weight 100
radius-server group-filter class
#
ip pool pool
section 0 172.16.1.2 172.16.1.100
#
ip route-static 0.0.0.0 0.0.0.0 1.1.1.2
#
aaa
authentication-scheme admin_radius
authentication-mode radius
service-scheme l2tpSScheme_1497877787064
ip-pool pool
domain default
radius-server radius
authentication-scheme admin_radius
service-type l2tp
#
l2tp-group l2tpvpn
tunnel password cipher %$%$b:5QM(/k!4Qpp+Z0DV`${fn.%$%$
allow l2tp virtual-template 1 remote client domain default
#
interface Virtual-Template1
ppp authentication-mode pap
remote service-scheme l2tpSScheme_1497877787064
ip address 172.16.1.1 255.255.255.0
alias L2TP_LNS_1
undo service-manage enable
#
interface GigabitEthernet 0/0/1
undo shutdown
ip address 1.1.1.1 255.255.255.0
#
interface GigabitEthernet 0/0/2
undo shutdown
ip address 10.1.1.1 255.255.255.0
#
interface GigabitEthernet 0/0/3
undo shutdown
ip address 10.1.3.1 255.255.255.0
#
firewall zone trust
set priority 85
add interface GigabitEthernet 0/0/2
#
firewall zone untrust
set priority 5
add interface GigabitEthernet 0/0/1
#
firewall zone dmz
set priority 85
add interface GigabitEthernet 0/0/3
add interface Virtual-Template1
#
security-policy
rule name service_td
source-zone trust
destination-zone dmz
source-address 10.1.2.0 24
destination-address 172.16.1.0 mask 255.255.255.0
action permit
rule name service_dt
source-zone dmz
destination-zone trust
source-address 172.16.1.0 mask 255.255.255.0
destination-address 10.1.2.0 mask 255.255.255.0
action permit
rule name l2tp_ul
source-zone untrust
destination-zone local
destination-address 1.1.1.0 mask 255.255.255.0
action permit
rule name radius_ld
source-zone local
destination-zone dmz
source-address 10.1.3.0 mask 255.255.255.0
action permit