Re: Oracle archive mode and hot backups
Date: 7 Aug 2009 13:11:16 GMT
> 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.
It may be that company's standard.
> 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:
They are necessary for recovery up to the point where they're no longer necessary.
> "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
> I'm interested in how you arrived at your apparently erroneous
> conclusions given the information posted above.
You're just making wild assumptions, based on very limited information given by a 3rd party when summing up what someone else has said. You don't know if he's planning to delete *all* archive logs. You don't know if those logs are backed up elsewhere. You don't know if those logs are applied to cumulative nightly backups.
Yes, it may be the DBA's clueless. Or it may be he's superb, & didn't want to go into all the details of explaining RMAN to a layman. The only way for the OP to find out is to ask more questions, based on the information he gets from places like cdos.
-- PrestonReceived on Fri Aug 07 2009 - 08:11:16 CDT