On Thu, Feb 25, 2010 at 1:19 AM, Mike McCarty Mike.McCarty@sbcglobal.netwrote:
Eero Volotinen wrote:
2010/2/24 Mike McCarty Mike.McCarty@sbcglobal.net:
Agnello George wrote:
Hi
We have an issue with one of our clients , they have a mail server
with
the /var/spool/imap partition as 150 GB . They need to take
differential
backup on to /backup partition ( a different HDD of total 250 GB space
) .
You've stated things in terms of solutions. You may possibly get better answers if you state your goal. There is some capability you are trying to achieve. Tell us what that is, and you may make more progress.
IOW, what is the purpose of the backup? As one mentioned, RAID may handle your needs.
Err.. raid is NOT backup solution.
Of course not. RAID is a means to achieve availability, which may be his goal. Karanbir already stated a means to do what he seemed to want, but it seemed not to satisfy his needs.
Unless the query is placed in terms of requirements and goals, instead of solutions, it'll be difficult to achieve satisfactory results.
The purpose of backup is some degree of disaster recovery, and perhaps also migration. If that's truly his goal, then ISTM that Karanbir suggested a viable solution to achieving avialability while also performing backup, by doing on-the-fly duplication of the data onto another file system which can then be backed up at liesure.
Doing so in a manner which ensures a true snapshot may be more difficult to achieve, while still ensuring availability. I normally do my backups in single user mode with all file systems mounted read only, except the one to receive the backup. That of course precludes availability during the backup procedure.
That's why I would like to see what he actually wants to achieve, instead of how he has chosen to go about it.
Mike
The requirement fro backup is not primarily for HDD failure , but human error failure . In case one of our user ( eg: the COO with huge mailbox size has delete all his certain very important mails, and he want to recover them , the contacts us as we are supposed to maintain his mail backup for a week, and we should restore his backup immediately ) this the main requirement for the backup and that too on the same server different partition .