Install forticlient in linux. Replace HOST, PORT, USER and PASS.

install_forticlientsslvpn_linux

sudo apt-get install expect
wget http://kb.cloud.it/files/tar-gz/forticlientsslvpn_linux_4-0-2281-tar.gz
tar xzf forticlientsslvpn_linux_4-0-2281-tar.gz
sudo mv forticlientsslvpn /opt/
cat > sslvpn << EOF
#!/usr/bin/expect -f
set timeout -1
cd /opt/forticlientsslvpn
spawn ./forticlientsslvpn_cli --server HOST:PORT --vpnuser USER
expect "Password for VPN:" {send -- "PASS\r"}
expect "to this server? (Y/N)\r" {send -- "y\r"}
 
expect eof
EOF
chmod +x sslvpn
sudo mv sslvpn /usr/local/bin/