But if I remove a disc or swap in anything that is not part of the raid it fails to boot. How can I tell md that it is ok to boot with missing discs/degraded array automatically?In the end as far as md is concerned even one of the four discs can support the whole system by itself, the data partition is another beast as it needs at least two drives but md should not be concerned with that as that is a pure btrfs raid.There's one odd quirk about maintaining FAT partitions under either Windows 2000 or XP you should know about: If you delete a file directly (without sending it to the Recycle Bin; using SHIFT DEL keys for example), it can be very difficult, if even possible, to recover that file!For some odd reason, these OSs zero-out the 'high bits' (upper 16 bits) of any FAT file's starting cluster number!What's more, this easy-to-use tool supports various operating systems including Windows XP, Windows Vista, Windows 7, Windows 8/8.1, Windows 10, etc.
All drives do contain exactly the same format: The data partition is raid6 btrfs, I'm currently trying to upgrade my capacity by swapping out a drive for a bigger one, since I can have two fails my first instinct was to just replace one of the drives and boot back up, restore the failed raid arrays with the newly installed drive and after the rebuild everything is back to normal.
Update 3 Installed older kernel by chrooting through live USB, still the same problem with the kernel, so it seems the problem is not due to after all.
I have faced this problem earlier too but back then, I just considered reinstalling distribution easier (I used to distro switch a lot).
This page examines the NTFS Boot Record for Windows 2000 (NT5) and Windows XP (NT5.1).
Although Windows 2000 and XP can both use the MS-FAT32 File System, we'd advise anyone interested in serious computing to run these operating systems in NTFS formatted partitions (rather than FAT32) for a number of reasons; which include better performance, less wasted space and greater security.