Strange case - ROCK / USB backup drives

I have run my Roon ROCK core for many years on the same passively - cooled generation 4 Intel NUC (It’s a MOCK really, but I make little demand on it with a modestly sized library and no use of DSP). My Roon database backs up on schedule to two external usb drives. Yesterday the scheduled backups failed on both drives, and they disappeared from the list of locations in setup/audio/backups.

I tried restarting the NUC, reinstalling the server software, and checked in the NUC BIOS to no avail. I couldn’t believe that 2 drives had failed simultaneously, so I suspected the ancient motherboard had developed a fault. I swapped to for a spare one I keep. The server came back up as usual, but continued not to see the backup drives.

Finally, I decided to check the the drives themselves by scanning them in a Windows PC - it needed to repair both of them, and when I plugged them back into the NUC they appeared again and are back up and running with no loss of backups.

Just for interest, does anyone know what might have happened to the drives on the same day to cause the fault, especially considering that one is a hard drive and one is an SSD?

What’s the disk format on these drives?

Thank you for your reply. They are both NTFS. Any thoughts on what happened?

Wild guess, but since they both crapped out at the same time while they were attached to the NUC, and then had to be repaired in Windows, my best bet would be a Linux kernel driver error.

Before RoonOS build 254 that was released last fall, it used the older Linux driver for NTFS. This one had some issues, mainly because NTFS is a proprietary and questionably documented file system that is very difficult to support fully. One of this was known to cause file system corruption by not properly enforcing writing only to completely error-free NTFS disks, and there was more.

Since RoonOS build 254, it uses the new NTFS driver that was added to the Linux kernel in spring 2022, made possible by a generous (and surprising) donation of code by Paragon Software, who had invested lots of efforts into reverse engineering NTFS.

This new driver is much better and much more strict about NTFS file system safety. After the build 254 RoonOS update, there were lots of cases on the forum where the new driver refused to mount disks that the older RoonOS had accepted.

The apparently most frequent cause of such refusal was unsafely removing (simply unplugging) the drive from a Windows machine (causing a “dirty unmount” NTFS flag), but I think there may have been others where they disks where never (at least knowingly) attached to Windows - just purchased (with NTFS preformatted) and attached to the NUC. At least that is my take from the many cases I have seen.

With the older driver it was definitely a bad idea to use NTFS with Linux for anything important, and the ROCK documentation specifically recommends against using it for external disks that are connected to ROCK. (

Even with the newer driver, and despite Paragon’s efforts, NTFS is still proprietary and reverse engineered, and it’s entirely possible that occasional errors occur without doing anything specific, simply caused by bugs in the Linux driver.

According to Danny, they are looking into a solution that avoids the necessary chkdsk after an unclean removal from Windows, but IMHO the advice to use a different file system remains valid, because the NTFS driver will always have deficiencies compared to an openly developed file system like Linux’s native EXT4 or a much simpler one like exFAT


I know it’s a lot of work, but consider moving to exFAT.

Many thanks for this generous and comprehensive reply.

When I removed the drives from the Windows PC after scanning them, I was careful to ensure that I demounted them safely. It was then that they started to be seen again by ROCK when I reconnected them to the NUC. So it is certainly plausible that this cleared a “dirty demount NTFS flag” and allowed the drives to work again.

Unfortunately, when building the ROCK NUC many years ago I was not thorough enough and missed the advice on the formatting the usb drives. I will certainly consider reformatting at least one of the drives for added data security.

Kind regards


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