Critical SMB issue with Final Cut Pro 12.4 on macOS 27.2

I recently updated to 27.2.1 after having issues in 27.2, and everything seems to be working as expected now. Can anyone else confirm this? Here was what I tested:

Tested today on two Macs against the same SMB share and the same Final Cut Pro 12.4 library:

• macOS 27.2 (26B123): the library’s symlinks in Original Media show as plain 1067-byte files, media offline, relink only holds until FCP is quit.
• macOS 27.2.1 (26B131): same files show as symlinks, media online, new “leave files in place” imports survive quit and reopen.

Nothing changed on the server between the two tests. 27.2.1 (released Nov 9) seems to fix it. Existing libraries came back without relinking.

I don't work for or represent Apple. The following is not a policy statement; it's just an informed opinion. I worked for 10 years developing SQL Server and debugging it at the source code level.

The support status of FCP libraries on NAS is somewhat unclear. For years, I have tried to warn people against doing that. The FCP library is composed of multiple SQLite relational databases undergoing almost constant writes. Those databases are exquisitely sensitive to transactional errors if the I/O system fails to work perfectly or fails to adhere to the behavioral "contract" expected by the application data management layer.

But there is an official Apple article that implies it is supported -- if you adhere to specific requirements.

"Use shared storage with Final Cut Pro"

Use shared storage with Final Cut Pro - Apple Support

- Samba 4.3.4 or later configured with modules for Apple compatibility

- vfs objects = catia fruit streams_xattr

That implies SMB1, SMB2, SMB3 or SMB4 are not sufficient since those are not a backward-compatible superset of Samba 4.3.4 and later. So I question how many people have adhered to these requirements.

Even if so, there are also questions about exactly what "supported" means in this context. Technically, it means this can be done; i.e., it is conceptually possible. But "supported" does not imply Apple will assign a senior development engineer or network engineer, configure NAS test servers for each make and model, write extensive NAS usage documentation, and continuously liaise with each NAS vendor.

Years ago when the Lumaforge Jellyfish NAS was first sold, that company had high-level expert engineering support. The device was expensive, but it was extensively tested with FCP and experts tuned it to work reliably. That is in the past, and that level of support has never been available for typical consumer NAS products.

You are your own escalation resource in these cases. When something goes wrong, FCP customers must understand that this typically requires engineering-level expertise on multiple levels: FCP, macOS, network, the specific NAS, etc. Troubleshooting can require synchronized data gathering on both client and server, and source-level interpretation of that. No retail product support organization can do that.

A more recent article, "Format storage devices for Final Cut Pro, Motion, and Compressor," says only APFS is supported (which by definition excludes NAS).

Format storage devices for Final Cut Pro, Motion, and Compressor - Apple Support

Shared NAS-based project libraries can be reliably done by Resolve because that uses a true client/server relational database (PostgreSQL), not a local database file pushed over to a NAS. FCP would need to be fundamentally rewritten to work this way.

I would help if you can ask creative.space this question:

"Can you confirm that our particular creative.space server, including its current firmware/software version and SMB share configuration, meets Apple's requirements in Support Article 101919 for storing active Final Cut Pro libraries -- specifically Samba 4.3.4 or later with the catia, fruit, and streams_xattr VFS modules enabled?"

Thank you for your message, I did work with Jellyfish server, it'was really nice until OS update that broke performances....

I have a temporary workaround, copy only the library localy in order to work, and then copy it into the NAS when th job is done....

Waiting Apple fix.

@terryb I use creative.space which is a Linux ZFS NAS utilizing SMB. Another user of this storage noted that their issue resolved after the update. I tested it on a newly updated Mac from 15.x.x to 27.2.1. FCP 12.4 worked as expected and the file pointers looked normal from the terminal commands I was using.

I'm not holding my breath until more people share their results.

"Please investigate a possible..."

You know we're all just end users helping each other out here, right? There's no Apple support in these forums. There are some irritating bugs in macOS 27, but I'm not aware of any NAS connection issues. I'd call Apple support about this, for sure.

Thank Joema for that explanation. I've been seeing NAS issues posted on FCP(x) forums since it's release. FCP's biggest weakness, workgroup sharing, which I understand is related to the NAS issues... (sigh)

@MaximeBichon We are also heavy users of 10GbE NAS storage for both FCP libraries and media (always stored externally). I have not updated the OS to 27 on our M1 Ultra Mac Studio or M4 Pro Mac Minis yet. Please report back if you discover anything new. Thank you.

Yes that's right, I was hoping that Apple could reed some bug / issues in order to fix them.

I've send it to FINAL CUT REPORT form.... I don't know if there is a same form for their OS.

Thank you @Gh-sup for reporting your findings. Which NAS are you using? I'm very curious to hear if 27.2.1 is a fix for others with SMB NASes. Once we have a lull in projects I'd like to update.