[pfexec]

Took 10 seconds to find:

https://philip.greenspun.com/blog/2024/02/29/why-is-the-btrf...

> We had a few seconds of power loss the other day. Everything in the house, including a Windows machine using NTFS, came back to life without any issues. A Synology DS720+, however, became a useless brick, claiming to have suffered unrecoverable file system damage while the underlying two hard drives and two SSDs are in perfect condition. It’s two mirrored drives using the Btrfs file system

[zejn]

Synology does not use vanilla btrfs, they use a modified btrfs that runs over mdraid mirror, which somehow communicates with btrfs layer to supposedly fix errors, when they occur. It's not clear how far behind that fork is.

[ksec]

Synology are still shipping kernel 5.10 on their latest model. And 4.4 only a few years prior.

I am hoping we will get ZFS from Ubnt NAS via update.