Steps to configure Remote SSL VPN in FortiGate with CLI
Create a ssl.root interface for SSL VPN Tunnel
config system interface
 edit "ssl.root"
        set vdom "root"
        set type tunnel
        set alias "Remote SSL VPN interface"
end
Create an IP Pool called SSLVPN_IP_POOL (10.212.134.200 – 10.212.134.210) to assign IP Addresses for Remote SSL VPN Users
config firewall address
    edit "SSLVPN_IP_POOL"
        set type iprange
        set associated-interface "ssl.root"
        set start-ip 10.212.134.200
        set end-ip 10.212.134.210
end
Create an local user called sslvpn with password defined
config user local
edit "sslvpn"
        set type password
        set passwd P@ssw0rd
    end
Create a group called SSLVPN_GROUP and assign sslvpn as member
config user group
 edit "SSLVPN"
        set member "sslvpn"
 end
Enable Tunnel Mode and assign SSLVPN_IP_POOL in Full Access Profile
config vpn ssl web portal
    edit "full-access"
        set tunnel-mode enable
        set ip-pools "SSLVPN_IP_POOL"
end
Configure SSL VPN with the following
- SSL Certificate to be used – Default is using FortiGate Selfsign Certificate
- IP Addresses to be assigned to Remote SSL VPN Client
- SSL VPN Port No – Default is 443, and we had changed it to 12443
- Source Interface – External Interface
- Change the Default-Portal to full-access
- DNS Servers – Point to Internal AD/DNS Server for name resolution
config vpn ssl settings
    set servercert "AventisLab.com"
    set tunnel-ip-pools "SSLVPN_IP_POOL"
    set port 12443
    set source-interface "wan1"
    set source-address "all"
    set default-portal "full-access"
    set dns-server1 192.168.1.200
    set dns-server2 192.168.1.201
    set dtls-tunnel enable
end
SSL VPN Settings in Web UI

Create the following firewall policy to allow traffics from SSLVPN to LAN and via visa
- SSLVPN-LAN – allow traffic from SSLVPN tunnel to LAN for SSLVPN_GROUP only
- LAN-SSLVPN – allow traffic from LAN to SSLVPN tunnel for SSLVPN_GROUP only
config firewall policy 
edit 100
        set name "SSLVPN-LAN"
        set srcintf "ssl.root"
        set dstintf "internal"
        set srcaddr "all"
        set dstaddr "192.168.1.0"
        set action accept
        set schedule "always"
        set service "ALL"
        set logtraffic all
        set groups "SSLVPN_GROUP"
    next
    
    edit 101
    	set name "LAN-SSLVPN"
        set srcintf "internal"
        set dstintf "ssl.root"
        set srcaddr "192.168.1.0"
        set dstaddr "all"
        set action accept
        set schedule "always"
        set service "ALL"
        set logtraffic all
        set groups "SSLVPN_GROUP"
    end
Configure the FortiClient with the FQDN / IP Address of WAN Interface with custom port = 12443 with username = sslvpn

Login to SSL VPN successfully

Some useful commands to troubleshoot on Remote SSL VPN
Show Active SSL VPN users with execute vpn sslvpn list
FG60E # execute vpn sslvpn list
SSL VPN Login Users:
 Index   User    Auth Type      Timeout         From     HTTP in/out    HTTPS in/out
 0       sslvpn          1(1)            296     14.1.227.206   0/0     0/0
SSL VPN sessions:
 Index   User    Source IP      Duration        I/O Bytes       Tunnel/Dest IP
 0       sslvpn          14.1.227.206    670     24470/35484    10.28.28.10
To disconnect SSL VPN User – Replace the with the correct ID
execute vpn sslvpn del-tunnel <index>
To disconnect all SSL VPN Users
execute vpn ssl del-all tunnel
Reference Link
