MySQL Bugs: #57246: --apply-log is not atomic - if it fails it might corrupt the backup image

Bug #57246	--apply-log is not atomic - if it fails it might corrupt the backup image
Submitted:	5 Oct 2010 12:31	Modified:	11 Dec 2011 7:15
Reporter:	Victor Kirkebo	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Enterprise Backup	Severity:	S3 (Non-critical)
Version:	3.5	OS:	Any
Assigned to:		CPU Architecture:	Any

Description:
Corruption of the full backup image is a problem with the current implementation of apply-log; if something goes wrong in the middle of the operation you may end up with a corrupted full backup image. For now the user should probably make sure to have an extra copy of the full backup before issuing --apply-log commands. In the future it would be nice if mysqlbackup could make the whole --apply-log "transactional" e.g. by working with a temporary copy of the full backup data until it succeeds.

How to repeat:
Please read the source code of mysqlbackup for the apply-log commands, e.g. the function copy_incremental_to_full_backup.
An example of a bug that made incremental apply-log fail: bug#57222