There seems to be a major design flaw with BTRFS that needs to be better documented, to avoid massive data loss.
Tested with Raid 1 on Ubuntu Kernel 4.15 The use case being tested was a Virtualbox VDI file created with NODATACOW attribute, (as is often suggested, due to the painful performance penalty of COW on these files.) However, if a device is temporarily dropped (this in case, tested by disconnecting drives.) and re-connects automatically next boot, BTRFS does not in any way synchronize the VDI file, or have any means to know that one of copy is out of date and bad. The result of trying to use said VDI file is.... interestingly insane. Scrub did not do anything to rectify the situation.
<<attachment: remi.vcf>>
