Re: Oracle archive mode and hot backups
Date: Fri, 07 Aug 2009 00:07:02 +0200
Message-ID: <eokm75dutbgpbihkt5f7304ho4ds1vg2ll_at_4ax.com>
On Thu, 6 Aug 2009 14:35:00 -0700 (PDT), Jeff Morgan <jefang6448_at_gmail.com> wrote:
>We have an Oracle 10g database on UNIX moving to a new data center.
>We are still testing a stage server. The DBA state that the standard
>is to have the database in archive mode to allow for hot backups.
>
>We ran into an issue when the 17 gigs of space in the archive folder
>was full. The DBA's solution was to write a script to automatically
>delete archive files when the folder reaches 10 gigs. I questioned
>the need to create archive files if they are ultimately deleted. The
>DBA stated that the actual archive files are not used and can be
>deleted. The archive mode is only used for hot backups.
>
>From what I have researched, the archive files are required for
>recovery. Can anyone shed some light on the whole archive/hot backup?
It is quite simple. Hot backup or cold backup really doesn't matter. If you want to recover your database you need to retain all archives generated between two backups. If you run out of disk space for archivelogs, you need either to buy extra disk space, or you need to backup your archives as well.
RMAN can do all this. RMAN can perform both cold (database mounted)
and hot backups (database open). 'User managed hot backup' (what you
call hot backup per se) is obsolete.
Your DBA needs to be retrained or released from duty: he doesn't
understand basic backup and recovery strategies.
-- Sybrand Bakker Senior Oracle DBAReceived on Thu Aug 06 2009 - 17:07:02 CDT