Re: Oracle archive mode and hot backups

From: ddf <oratune_at_msn.com>
Date: Fri, 7 Aug 2009 05:51:08 -0700 (PDT)
Message-ID: <aa7b2817-0e61-43fd-a988-bffd01a560eb_at_d21g2000vbm.googlegroups.com>



On Aug 7, 6:13 am, "Preston" <dontwant..._at_nowhere.invalid> wrote:
> John Hurley wrote:
> > On Aug 6, 8:05 pm, Palooka <nob..._at_nowhere.com> wrote:
>
> > snip
>
> > > > If you are not really in production on this system ... ditching
> > > > the archive logs can be done as needed probably.
>
> > > > Maybe the archive log files are being put into different locations
> > > > simultaneously ( multiple copies ) so that copy that was getting
> > > > ditched really is un-necessary.
>
> > > > Best advice is to ask the relevant DBA a couple more questions
> > > > and get them to explain exactly what is going on.
>
> > > What a load of bollocks. Sybrand is entirely right. What on earth
> > > is the
>
> > Best advice is to ask the relevant DBA a couple more questions and get
> > them to explain exactly what is going on.
>
> Exactly that. Jeff didn't say this script would delete /all/ the
> archive logs (it might leave whatever's necessary to recover between
> backups), nor if these are the only copies, not if it's a full backup
> every night etc etc. Nobody has enough information to say whether this
> is bad or not, but of course that won't stop the usual suspects
> shouting 'hang him!'.
>

Let's look at what has been reported thus far:

"The DBA state that the standard
is to have the database in archive mode to allow for hot backups. "

Again, it's not a 'standard', it's an available option. And, yes, archivelog mode is required to allow for a hot (online) backup strategy, priimarily because these logs are NECESSARY for recovery, a concept apparently lost on this 'DBA' as evidenced by this next quote:

"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. ****"

Given that level of 'knowledge' one expects these archivelogs are

  • considered irrelevant to the recovery process by the 'DBA'
  • are NOT treated to a proper backup prior to deletion

From that we can deduce:

  • this 'DBA' has no concept of recovery from a hot (online) backup and feels that simply the backup itself is sufficient
  • this 'DBA' has yet to attempt a recovery from one of his hot backups

I'm interested in how you arrived at your apparently erroneous conclusions given the information posted above.

> --
> Preston- Hide quoted text -
>
> - Show quoted text -

David Fitzjarrell Received on Fri Aug 07 2009 - 07:51:08 CDT

Original text of this message