mysql backups (was Re: Remote backups, reading from and writing to the same file)

Hans Nieser hans at
Sat Jan 14 19:28:16 PST 2006

N.J. Thomas wrote:
> * Hans Nieser <h.nieser at> [2006-01-13 00:25:14 +0100]:
>> Among the things being backed up are my mysql database tables. This
>> made me wonder wether the backup could possibly get borked when mysql
>> writes to any of the mysql tables while tar is reading from them.
> Yes. While MySQL is writing to the the database, it will put the files
> on the disk in an inconsistent state. If you happen to copy those files
> while they are in that state, MySQL will see a corrupted database.

Thanks for the replies all. I think for the short term I will simply 
lock/shutdown my MySQL server (it is a home-server after all), in the long 
term I think I will look into snapshotting. I've also been thinking about 
just doing an SQL dump with mysqldump right before the backup, that will 
still copy along the tables which may be in an inconsistent state, but 
also the sql dump.

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