Best Bonjour scenario configuration for DT3 server and DTTG

I have DT3 Server (3 seats) with Bonjour server on my iMac setup as the only Bonjour server allowing incoming connections. The iMac has several scripts that monitor folders and is used for most of my data management. I want advice on setup due to past experience using my intuition that has led to major troubleshooting.
I also have DT3 on my Air and my MacPro with incoming Bonjour connections deselected on those two devices. I want to keep Bonjour as the only connection/sync method for all devices.
I would like to setup and maintain one academic database which would interface primarily with DTTG and be the default launch db on the Air. Is it possible and recommended to create this new database on the Air and Bonjour sync Air to iPad? (It is my understanding that only one device on a network should allow incoming Bonjour. I want to avoid the iMac as the first location to open the academic db because that machine launches five large databases and scripts which are personal, nonacademic, and large users of local resources.
To recap:

  • Three DT3 server seats (iMac, MacPro, Air) and DDTG on one iPad
  • All current .dtBase2 files on iMac ~/Databases/
  • No databases currently setup on DTTG
  • Incoming Bonjour on iMac enabled; disabled on Air, MacPro, and DTTG
  • Want to avoid Dropbox, iCloud, and local sync stores if possible (just me, Bonjour, my Air, and my iPad for academic.dtBase2)
  • My backups are Time Machine and Backblaze


So the Air doesn’t have the databases you don’t want to

And yes, the Air can act as a Bonjour server of its own databases, syncing to the other Macs of the iOS device.

Like @markjule, I’m trying to configure Bonjour syncing on multiple Macs. I have two rather than @markjule’s more complex situation, but it has me scratching my head.

Do I understand Bonjour sync correctly in the following two paragraphs:

There is no “canonical” copy of a database synced over Bonjour between two Macs. Each database is an equal partner, and they’ll be identical after sync. So it doesn’t matter where the database first resided before sync.

However, the database needs to start out life on the Bonjour server – the Mac that accepts incoming links – but once it’s set up for syncing, the two databases are identical.

Is all of this correct?


You are correct in that sync is bidirectional by design, so once the databases are syncing there is no real master (though you may keep one machine in mind as having the master).

And it is ideal if databases begin in the server machine since Bonjour will not push databases.

So if you have an iMac as the server and a MacBook connected as a client, then you create a database on the MacBook you can’t push it to the iMac via the sync.
You could transfer the dtBase2 file manually or you could set up the MacBook as a Bonjour server, connect the iMac as a client, then import the database to the iMac. You could leave it set up this way or disable Bonjour on the MacBook and let the iMac now serve the new database.

Very helpful, particularly the tip about bidirectional Bonjour. Thanks so much.

Why? What’s the advantage there?

You’re welcome.

For some it may be psychologically comfortable to think this way.

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The initial post regarding config was good.

I recently in 2023 cleaned up and reinstalled Big Sur on my Air. When I attempt to setup Bonjour sync on the Air, the remote databases show up for import but do not complete syncing before timing out. I prevent both the Air (client) and MacBook (server) from sleeping during the process. I can ssh from the Air/client device to the MacBook/server device. No other sync stores are used on either device. Bonjour Incoming Connections are off on the Air and on for the MacBook. Both devices are on the same home network with manual IP addresses ( My smaller databases have successfully imported (from Remote to Local) on the Air, but the larger ones timeout. (Incidentally, the ssh pipe between devices breaks concurrently with the sync process failing.) :upside_down_face:

Apple’s Big Sur is the latest version you can use? 13.2.1 is current version.

Perhaps it is the network? Re-boot the router(s)?

That looks like a network problem. Are you on wlan or wire?

After rebooting the modem and router on my network, I get the small and medium-sized databases to sync. The two largest still fail after about 30 minutes of progress. I have a cable modem to wired router. Router to devices are wlan.
As I watch the DT3->Preferences->Sync window, the Bonjour connection randomly switches back and forth from Local Network (of the server Mac’s local address) to Local Network (offline). DT3 is only launched on two devices. One workaround sometimes temporarily works if I quit and relaunch DT3 on both devices.