- Download server file from the bottom of the page, https://terraria.org/
- I can't open the app, instead
cd /Mac/Terraria%20Server.app/Contents/MacOS/ chmod +x ./TerrariaServer && chmod +x ./TerrariaServer.bin.osxsudo codesign --sign - ./TerrariaServer.bin.osxsudo /usr/libexec/ApplicationFirewall/socketfilterfw --add ./TerrariaServer.bin.osx./TerrariaServer.bin.osxand allowing it in the setting, System Settings > Privacy & Secrutiy -> Security -> Allow- Setup port forwarding for your router
Source: