How does PT know that someone else is working w/ my session?
 

We got an unexpected error message today. We had one person working on the mix of a session in one location, and another person -- in a different location -- merely had that session open, and PT stated:

"User "John Doe" on machine "A" with IP address x.x.x.x has this session open. Please Save As a new session to continue saving changes."

According to both engineers, neither person is actually logged-in, and this is NOT a collaborative cloud session. How (and why) is ProTools aware of the other person's work? And if the session isn't collaborative, why wouldn't we be able to open the same file at the same time on different computers?

Re: How does PT know that someone else is working w/ my session?
 

Is the Session on shared storage? You'd see this if you had a session in Dropbox/etc. and open that on one system with "Prevent Others from Overwriting Open Session" enabled in Setup > Preferences > Collaboration, then open that session on another system.

Re: How does PT know that someone else is working w/ my session?
 

Are you talking about two totally different sets of duplicated session files in two different locations? Or two people accessing central file management to run two separate sessions from one set of project assets?

The behaviour makes complete and total sense in the latter situation to prevent users unexpectedly saving over other users work. Even Word or cloud storage like Dropbox or OneDrive will automatically create a unique project file if two people end up editing the same original session or word doc.

If it is the former, I would think it is probably just something simple related to the state of the session when it was duplicated rather than anything particularly snoopy from Avid’s end. If Pro Tools puts a flag in the project files somewhere indicating they are in use, that flag may well have made the move to the new location. Purely speculating with this bit, but it would be easy to test.

Re: How does PT know that someone else is working w/ my session?
 

^^^ This would be my guess as well. And even if people think they are not using cloud or shared network storage they easily can be. Seen enough times where folks working on stuff just don't know say the E: drive is a network share.

You can't have two people with a same shared session open, even if one thinks they are not editing the session. There is potential here to destroy work. Yes even if folks can get away with it much of the time.

What does "neither person actually logged in" mean? They *are* logged into their local computers and that may very well have network shares mounted, or default cloud storage available because of automatic login. You need to look at the details of what exact device/filesystem the session and it's files are on. All this can be as simple of mistakingly creating a symbolic link instead of copying a session folder etc.

Re: How does PT know that someone else is working w/ my session?
 

Sounds like you’re both working on the same session file on a network shared drive, Dropbox, Box, Google Drive, etc. This could not happen if you truly were working on separate local session copies.

Re: How does PT know that someone else is working w/ my session?
 

Sounds like a feature, not a bug. Which is good.

Dominic

Re: How does PT know that someone else is working w/ my session?
 

How does PT know that someone else is working w/ my session? must be PT magic :eek:
And people still wonder why it is called the "Industry Standard" :D

sorry couldn't resist ;)

Re: How does PT know that someone else is working w/ my session?
 

Followup to my previous post... this was added in 2020.5. From the Blog and Release Notes back then...

Re: How does PT know that someone else is working w/ my session?
 

The odd thing is that these two sessions are on different drives in different locations, and from what we can tell there wasn't any kind of remote connection between them. We do use Codemeter to allow the remote machine to access the authorization for Soundminer which resides on the other machine, but that *shouldn't* be enough to allow PT to recognize which sessions are open.

Re: How does PT know that someone else is working w/ my session?
 

You need to go look at what is going on. The obvious first guess is that somebody just had the session in use with the lock files that Jeffro described and y'all copied the lock file over with the session to the new location. By default the lock file will be <SessionName>.tmp in the session folder. But the file extension might have been changed in Preferences. Which itself turns out to be a useful warning -- copying open sessions is risky. Or maybe Pro Tools just crashed and left the lock file there... if you are not going to use this feature just turn it off in Preferences>Collaboration>Prevent others from Overwriting Open Session.

Making this all more robust would take a fair amount more work, and given Avid's struggles with cloud storage just like not a direction I'd encourage them to go (like you can end up wanting a running roster on disk of all active session and hosts they are running on, for what users, session is open heartbeats being updated and/or a way to poll a remote session to see if it's still alive etc. via messages on disk. It all gets messy fast).

And even with these lock file protections in place running Pro Tools on things like cloud collaboration is a very risky proposition, Pro Tools simply has not been properly redesigned to work in a distributed cloud environment.