Multi User Mac Os

[mcreighton]

I use BitTorrent Sync to  keep Lightroom catalogs in sync across three machines (Macs). One machine has two user accounts. It would be useful if the two way sync to a singled shared folder on that machine was enabled irrespective of which user was logged on. It is not obvious to me if that is possible, without each user having their own 'Peer' folder set up - which obviously duplicates files.

 

Any pointers gratefully received.

 

Mike

[trevellyan]

I think you can expect this to end badly. One thing that's recommended with Sync is to try to avoid changing the contents of a synced folder while Sync isn't running. Your plan will result in this happening each time you switch users.

[packy]

I don't think so. If I have a folder, say, /Users/Shared/BTSync, and I have users "bob" and "alice" running BitTorrent Sync that both point at that folder, Sync would only be running when you were actually in the process of switching users, during which time you wouldn't be changing the files. By the time you were actually running as a different user, Sync would be running again and keeping the files in Sync.

 

I'm in a similar situation: I've got a Mac Pro that I want to share with another user, but I'd rather not share user accounts. I've already got a folder that's being Sync-ed on the machine, but it stops being Synced when I log out and the other user logs in.  Having two separate folders, one for each user, is also sub-optimal, because Sync wouldn't be running for that other user while they're logged off, and they would have to wait after they logged on for Sync to update their copy of the files with all the changes from the other machines sharing the folder.

 

Part of the problem is that Sync is running as a user-space program on OS X, not as a background service. If Sync could run as root in the background, it could be syncing folders while users aren't even logged in.

[trevellyan]

By the time you were actually running as a different user, Sync would be running again and keeping the files in Sync.

 

First, recognize that each user has their own Sync database in ~Library/Application Support/BitTorrent Sync, which cannot be up to date for both users at the same time.

 

Now imagine user A is logged in. Sync is running and files are changing, either because user A changed them or because they changed on another peer. Now user A logs out and user B logs in. Sync starts and discovers that files have changed while it wasn't running. This instance of Sync doesn't know that it was another instance of Sync that made the changes. Therefore, this instance of Sync has been presented with changes that occurred while it wasn't running. This is a bad thing.

 

Even worse, imagine if you have fast user switching enabled. Now two instances of Sync could be fighting over the same folders at the same time. Yuck.

[packy]

Ugh. Each user has its own Sync database? Ok, that makes the whole thing messy. I was thinking that the Sync database was maintained within the directory itself, not per-user.

 

This would be so much easier if Sync could run as a single background process in its own user context.