Can corruption happen by powering off the computer (not properly shutting it down) during balance or scrub of a btrfs volume?
Can corruption happen by powering off the computer (not properly shutting it down) during balance or scrub of a btrfs volume?
Edit: including corruption of superblocks
Corruption should be automatically detected and fixed. The operations will resume on bootup.
However I wouldn't push your luck.
No, I don't thing scrubs / balances resume on boot up, they'd have to be started again.
Storage devices can fail at any time for any reason. Always have a backup.
Fwiw, I think BTRFS is better than ext4 and friends at actually detecting whether a block is corrupted or not.
"Better" in the sense that it actually has the ability to check for corruption at all, as all metadata and data are checksummed.
As long as the hardware functions as it should (e.g. respects barriers) and there is no software bug in the stack, no.
That's a highly unlikely scenario though. Make backups.
I had some kernel panics here and there... but the last one panic was fatal. Suddenly a lot of /usr/lib/lib<name>.so files were empty and also X11 stopped working...
As long as there are no problems with the btrfs code? Hahahahaha!! There are.
And also in any other filesystem's code or the block layers below the filesystem. As I said, unlikely scenario.
Since btrfs uses Copy on Write, as long as the data makes it onto disk in tact, any further btrfs operations on the data will be safe against sudden power loss. It might need the opportunity to repair some stuff once power is restored (scrub), but the data (and metadata) should still be there and recoverable, not left in some partial state that can't be resolved.
Theoretically, no.
In reality, possibly/yes!
What do you have?
Everyone saying it'll be fine is speaking theoretically. Practically I can attest to full and total file system corruption under this scenario.
Especially if you're using raid5 for multi disk.
No
No.
Yes there's always a chance corruption can happen from a hard power off, always keep reliable backups.