===== SoftEther VPN Server Installation =====

  * Run the following command to download the latest stable version of SoftEther VPN server:

   wget https://www.softether-download.com/files/softether/v4.42-9798-rtm-2023.06.30-tree/Linux/SoftEther_VPN_Server/64bit_-_Intel_x64_or_AMD64/softether-vpnserver-v4.42-9798-rtm-2023.06.30-linux-x64-64bit.tar.gz

   * Extract the archive:

  tar xvf softether-vpnserver-*.tar.gz

  * Change to the vpnserver directory.

  cd vpnserver/

  * Install the following dependency packages on the server:

  sudo apt install gcc binutils gzip libreadline-dev libssl-dev libncurses5-dev libncursesw5-dev libpthread-stubs0-dev

  * Then run the following command to start the build process:

  make

  * '**make**' will make two binaries from the source code.
  - vpnserver: The server binary.
  - vpncmd: SoftEther VPN command line management utility

  * move the vpnserver directory to /opt/ (standardize):

  cd ..
  sudo mv vpnserver /opt/softether

  * The VPN server can be started with:

  sudo /opt/softether/vpnserver start

  * Stop it with:

  sudo /opt/softether/vpnserver stop

  * To make SoftEther VPN server automatically start at boot time, create a systemd service unit:

  sudo nano /etc/systemd/system/softether-vpnserver.service

  * Add the following lines to this file:

  [Unit]
  Description=SoftEther VPN server
  After=network-online.target
  After=dbus.service
  [Service]
  Type=forking
  ExecStart=/opt/softether/vpnserver start
  ExecReload=/bin/kill -HUP $MAINPID
  [Install]
  WantedBy=multi-user.target

  * Save and close the file. Then start the VPN server:

  sudo systemctl start softether-vpnserver

  * Enable auto-start at boot time:

  sudo systemctl enable softether-vpnserver

  * You can check its status with:

  systemctl status softether-vpnserver


  * If it’s not running, check the journal to find out what’s wrong:

  sudo journalctl -eu softether-vpnserver

  * Check the listening ports:

  sudo  ss -lnptu | grep vpnserver

  * If firewall running, open the ports:

  sudo ufw allow 80,443,992,1194,555/tcp
  sudo ufw allow 1194,51612,53400,56452,40085/udp