File Modification While Tar is in Progress

[Paul Howarth]

Manish Kathuria wrote:
> I am using tar to take backups of multiple files and directories and 
> some of the files are about 500Mb. What happens when archiving of a 
> large file using tar (plus compression switches) is in progress and the 
> file is altered by some other program ? What do I need to do to make 
> sure that my archive is not corrupted ? For example, the large file in 
> question could be an IMAP mailbox on a Mail Server where I cannot afford 
> to stop either the MTA or the IMAP server to prevent the file from 
> getting altered.

Using an LVM snapshot should be one approach to solving this problem.

http://www.tldp.org/HOWTO/LVM-HOWTO/snapshots_backup.html

Paul.