You can start the database server directly from a terminal. This is usually not practical for a production environment, but it can be very useful when troubleshooting problems.
If your server needs to handle Windows clients, you can also launch the link server in a different terminal to ensure that both services work.
You can view the output of both services directly in the terminal in which you launch them as they start and handle requests.
In a terminal, enter the following command:
$ /Applications/Toon Boom Harmony 15.0 Advanced Network/tba/macosx/bin/tbdbserver
In another terminal, enter the following command:
$ /Applications/Toon Boom Harmony 15.0 Advanced Network/tba/macosx/bin/Link_srv