How to run a command upon startup of MacOS Catalina?

Question

I have installed SoftEther VPN on my Mac with MacOS Catalina and it works great after I manually start it. Upon a reboot the VPN does not come up though.

I currently have to open a Terminal window and type in the command ./Downloads/vpnserver/vpnserver start

I don't really like to have it sitting in a folder in Downloads.

1. Where should I move it? I'm logged in as a user.
2. How can I have it automatically started when my Mac starts up?

Answer 1

Generally I put things in /usr/local/vpnserver for example. See this answer for details about the purpose of various unix-based directories.

You can create Launch Daemons to have the vpn start when your computer starts. These are located in /Library/LaunchDaemons. An example file might be...

/Library/LaunchDaemons/vpnserver.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" “http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
  <dict>
     <key>Label</key>
     <string>vpnserver</string>
     <key>RunAtLoad</key>
     <true/>
     <key>KeepAlive</key>
     <true/>
     <key>Program</key>
     <string>/usr/local/vpnserver/vpnserver</string>
     <key>ProgramArguments</key>
     <array>
       <string>start</string>
     </array>
  </dict>
</plist>

You can start the daemon or stop it with the following commands, respectively...

sudo launchctl load -w /Library/LaunchDaemons/vpnserver.plist
sudo launchctl unload -w /Library/LaunchDaemons/vpnserver.plist