FortiClient as dialup client

This is a sample configuration of dialup IPsec VPN with FortiClient as the dialup client.

You can configure dialup IPsec VPN with FortiClient as the dialup client using the GUI or CLI.

If multiple dialup IPsec VPNs are defined for the same dialup server interface, each phase1 configuration must define a unique peer ID to distinguish the tunnel that the remote client is connecting to. When a client connects, the first IKE message that is in aggressive mode contains the client's local ID. FortiGate matches the local ID to the dialup tunnel referencing the same Peer ID, and the connection continues with that tunnel.

To configure IPsec VPN with FortiClient as the dialup client on the GUI:

1. Configure a user and user group.

   1. Go to User & Authentication > User Definition to create a local user vpnuser1.

   2. Go to User & Authentication > User Groups to create a group vpngroup with the member vpnuser1.

2. Go to VPN > IPsec Wizard and configure the following settings for VPN Setup:

   1. Enter a VPN name.

   2. For Template Type, select Remote Access.

   3. For Remote Device Type, select Client-based > FortiClient.

   4. Click Next.

3. Configure the following settings for Authentication:

   1. For Incoming Interface, select wan1.

   2. For Authentication Method, select Pre-shared Key.

   3. In the Pre-shared Key field, enter your-psk as the key.

   4. From the User Group dropdown list, select vpngroup.

   5. Click Next.

4. Configure the following settings for Policy & Routing:

   1. From the Local Interface dropdown menu, select lan.

   2. Configure the Local Address as local_network.

   3. Configure the Client Address Range as 10.10.2.1-10.10.2.200.

   4. Keep the default values for the Subnet Mask, DNS Server, Enable IPv4 Split tunnel, and Allow Endpoint Registration.

   5. Click Next.

5. Adjust the Client Options as needed, then click Create.

6. Optionally, define a unique Peer ID in the phase1 configuration:

   1. Go to VPN > IPsec Tunnels and edit the just created tunnel.

   2. Click Convert To Custom Tunnel.

   3. In the Authentication section, click Edit.

   4. Under Peer Options, set Accept Types to Specific peer ID.

   5. In the Peer ID field, enter a unique ID, such as dialup1.

   6. Click OK.

To configure IPsec VPN with FortiClient as the dialup client using the CLI:

1. In the CLI, configure the user and group.

   config user local
       edit "vpnuser1" 
           set type password
           set passwd your-password
       next 
   end
   config user group
       edit "vpngroup" 
           set member "vpnuser1"
       next 
   end				

2. Configure the internal interface. The LAN interface connects to the corporate internal network. Traffic from this interface routes out the IPsec VPN tunnel. Creating an address group for the protected network behind this FortiGate causes traffic to this network group to go through the IPsec tunnel.

   config system interface 
       edit "lan"
           set vdom "root"
           set ip 10.10.111.1 255.255.255.0
       next
   end
   config firewall address
       edit "local_subnet_1" 
           set subnet 10.10.111.0 255.255.255.0 
       next 
       edit "local_subnet_2" 
           set subnet 10.10.112.0 255.255.255.0 
       next 
   end 
   config firewall addrgrp
       edit "local_network" 
           set member "local_subnet_1" "local_subnet_2" 
       next 
   end 

3. Configure the WAN interface. The WAN interface is the interface connected to the ISP. It can work in static mode (as shown in this example), DHCP, or PPPoE mode. The IPsec tunnel is established over the WAN interface.

   config system interface 
       edit "wan1"
           set vdom "root"
           set ip 172.20.120.123 255.255.255.0
       next
   end

4. Configure the client address pool. You must create a firewall address to assign an IP address to a client from the address pool.

   config firewall address
       edit "client_range"
           set type iprange
           set comment "VPN client range"
           set start-ip 10.10.2.1
           set end-ip 10.10.2.200
       next
   end

5. Configure the IPsec phase1-interface. In this example, PSK is used as the authentication method. Signature authentication is also an option.

   config vpn ipsec phase1-interface
       edit "for_client"
           set type dynamic
           set interface "wan1"
           set mode aggressive
           set peertype one
           set peerid "dialup1"
           set net-device enable
           set mode-cfg enable
           set proposal aes128-sha256 aes256-sha256 aes128-sha1 aes256-sha1
           set dpd on-idle
           set xauthtype auto
           set authusrgrp "vpngroup"
           set assign-ip-from name
           set ipv4-name "client_range"
           set dns-mode auto
           set ipv4-split-include "local_network"  
           set save-password enable
           set psksecret your-psk
           set dpd-retryinterval 60
       next
   end

6. Configure the IPsec phase2-interface.

   config vpn ipsec phase2-interface 
       edit "for_client" 
           set phase1name "for_client" 
           set proposal aes128-sha1 aes256-sha1 aes128-sha256 aes256-sha256 aes128gcm aes256gcm chacha20poly1305 
       next 
   end 

7. Configure the firewall policy to allow client traffic flow over the IPsec VPN tunnel.

   config firewall policy 
       edit 1 
           set name "inbound" 
           set srcintf "for_client" 
           set dstintf "lan" 
           set srcaddr "client_range" 
           set dstaddr "local_network" 
           set action accept 
           set schedule "always" 
           set service "ALL" 
       next 
   end

To configure FortiClient:

1. In FortiClient, go to Remote Access and click Add a new connection.

2. Set the VPN to IPsec VPN and the Remote Gateway to the FortiGate IP address.

3. Set the Authentication Method to Pre-Shared Key and enter the key.

4. Expand Advanced Settings > Phase 1 and in the Local ID field, enter dialup1.

5. Configure remaining settings as needed, then click Save.

6. Select the VPN, enter the username and password, then select Connect.

Diagnose the connection

Run diagnose commands to check the IPsec phase1/phase2 interface status. The diagnose debug application ike -1 command is the key to troubleshoot why the IPsec tunnel failed to establish.

1. Run the diagnose vpn ike gateway list command. The system should return the following:

   vd: root/0
   name: for_client_0
   version: 1
   interface: port1 15
   addr: 172.20.120.123:4500 ->172.20.120.254:64916
   created: 37s ago
   xauth-user: vpnuser1
   assigned IPv4 address: 10.10.1.1/255.255.255.255
   nat: me peer
   IKE SA: created 1/1 established 1/1 time 10/10/10 ms
   IPsec SA: created 1/1 established 1/1 time 0/0/0 ms
   id/spi: 1 b40a32d878d5e262/8bba553563a498f4
   direction: responder
   status: established 37-37s ago = 10ms
   proposal: aes256-sha256
   key: f4ad7ec3a4fcfd09-787e2e9b7bceb9a7-0dfa183240d838ba-41539863e5378381
   lifetime/rekey: 86400/86092
   DPD sent/recv: 00000000/00000a0e

2. Run the diagnose vpn tunnel list command. The system should return the following:

   list all ipsec tunnel in vd 0
   =
   =
   name=for_client_0 ver=1 serial=3 172.20.120.123:4500->172.20.120.254:64916 tun_id=172.20.120.254
   bound_if=15 lgwy=static/1 tun=intf/0 mode=dial_inst/3 encap=none/984 options[03d8]=npucreate_dev no-sysctlrgwy-chgrport-chg frag-rfcaccept_traffic=1
   parent=for_client index=0
   proxyid_num=1 child_num=0 refcnt=12 ilast=3 olast=3 ad=/0
   stat: rxp=1 txp=0 rxb=16402 txb=0
   dpd: mode=on-idle on=1 idle=20000ms retry=3 count=0 seqno=0
   natt: mode=keepalive draft=32 interval=10 remote_port=64916
   proxyid=for_client proto=0 sa=1 ref=2 serial=1 add-route
   src: 0:0.0.0.0-255.255.255.255:0
   dst: 0:10.10.1.1-10.10.1.1:0
   SA: ref=4 options=2a6 type=00 soft=0 mtu=1422 expire=42867/0B replaywin=2048
   seqno=1 esn=0 replaywin_lastseq=00000001 itn=0
   life: type=01 bytes=0/0 timeout=43189/43200
   dec: spi=36274d14 esp=aes key=16 e518b84b3c3b667b79f2e61c64a225a6
   ah=sha1 key=20 9cceaa544ed042fda800c4fe5d3fd9d8b811984a
   enc: spi=8b154deb esp=aes key=16 9d50f004b45c122e4e9fb7af085c457c
   ah=sha1 key=20 f1d90b2a311049e23be34967008239637b50a328
   dec:pkts/bytes=1/16330, enc:pkts/bytes=0/0
   npu_flag=02 npu_rgwy=172.20.120.254 npu_lgwy=172.20.120.123npu_selid=0 dec_npuid=2 enc_npuid=0
   name=for_clientver=1 serial=2 172.20.120.123:0->0.0.0.0:0
   bound_if=15 lgwy=static/1 tun=intf/0 mode=dialup/2 encap=none/536 options[0218]=npucreate_dev frag-rfcaccept_traffic=1
   proxyid_num=0 child_num=1 refcnt=11 ilast=350 olast=350 ad=/0
   stat: rxp=0 txp=0 rxb=0 txb=0
   dpd: mode=on-idle on=0 idle=20000ms retry=3 count=0 seqno=0
   natt: mode=none draft=0 interval=0 remote_port=0