Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> c.d.o.server -> Re: Backup - hot or not?

Re: Backup - hot or not?

From: Glen A Stromquist <glen_stromquist_at_no.spam.yahoo.com>
Date: Thu, 13 Mar 2003 17:22:37 GMT
Message-ID: <x73ca.22591$UV6.1437439@news1.telusplanet.net>


Richard Foote wrote:
> "Preston Kemp" <dontwantany_at_nowhere.com> wrote in message
> news:MPG.18da88635b065e0898968b_at_news.cable.ntlworld.com...
>

>>Hi folks, I'm going to install 8i & setup a new database for a client
>>next week, but I'm struggling to decide what to do about backups. It
>>only needs to be available during normal office hours.
>>
>>They've been using a V7 database for a few years, & just take it down
>>every night & do a dump. They're happy enough to lose a day's data -
>>weird but that's the way it is!
>>
>>My question is what's the benefit, if any, of switching them to hot
>>backups? I presume the downside is the overhead of switching on archive
>>log mode.
>>
>>The system specs are PIII 500 Poweredge, 512MB RAM, 7 disks, max. 30
>>concurrent users, schema dump is around 1.7Gb. Any opinions gratefully
>>received, either on backup strategy or setup in general (I.e. how to
>>split the files, RAID etc). Beer tokens for the best reply ;-)
>>

>
>
> Hi Preston,
>
> If they're happy, they're happy I guess.
>
> But I would seriously look at migrating them to a supported version of
> Oracle as a start.
>
> I would also recommend moving the database to archivelog mode and going that
> one step further and protect them from any data loss. They might be happy to
> lose one day but they might be ecstatic to lose nothing when the time comes.
>
> Whether or not you use a hot/cold backup is not too much of an issue if you
> have a suitable down window each night. Note though that the database has to
> "warm up" when it restarts and may result in some unnecessary performance
> issues each morning. Note that a cold backup is more "simplistic" and can be
> fully restored and started if required. They're basically your plus/minuses.
>
> I would look at using RMAN (after your migration) and schedule nightly
> online backups as required. With RMAN you don't suffer the overheads of hot
> backups, have some security regarding the validity of the backups, improve
> your resume skills and with archiving have a fully protected, no performance
> impact backup strategy.
>
> If RMAN isn't your cuppa tea (or migration for some unacceptable reason is
> not an option), then either hot/cold could quite happily be used (based on
> the above issues).
>
> Good Luck
>
> Richard
>
>

I agree, I would put it in archivelog mode at the very least, and schedule and online backup nightly and cold backup monthly or thereabouts. If the DB has a lot of idle time like you say you could easily do a coldbackup nightly instead of an online, then you'd have the option of easily recovering to the point in time of the backup, or recovering up to the point of failure. (you can do the same with a "hot" backup, but IMO its easier to recover a cold backup if you are just going to recover to the time the backup was taken.)

I am also in the habit of doing an export on each DB during quieter hours, just for that extra insurance and for updating clones/development versions

hth Received on Thu Mar 13 2003 - 11:22:37 CST

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US