Re: RMAN archive log best practices

Evan wrote:
>
> Hello and thanks in advance for any help you can give.
>
> I am finally joining the world of RMAN and need some help determining
> the best way to handle the archive logs.
>
> The question is at the end, so please keep reading.
>
> Thanks,
>
> Evan
>
> Which is better, "keep until" or set management class to retain forever
> and delete the unneeded logs.
>
> Here are our requirements:
> We need to take
> daily (keep 14 days),
> weekly (keep 5 weeks),
> monthly (keep 12 months) and
> annual (keep 2-7 years depending on app) backups.
>
> We need to minimize our tape usage (management has spoken).
>
> We need point in time recovery to X months (depending on application),
> then snapshot recovery (to end of month, end of year) after that.
>
> We need to clean out the logs frequently due to disk constraints, so we
> currently copy logs to tape, then delete logs as often as every 15 minutes.
>
> Our environment is
> Oracle 9.2.0.x to 10.1.0.3 on Solaris, 64 bit.
> TDPO (IBM Tivoli tape interface) 5.2
> The management class parameters include "Keep forever, can delete".
>
> Problem:
>
> 1) Backup all archives (delete off disk, keep forever):
>
> backup filesperset 10
> format '%d_arch_%t_%s_%p'
> tag 'SIDNAME arch'
> (archivelog like '/u01/app/oracle/admin/SIDNAME/arch/%'
> delete input);
>
> 2) Take yearly database backup (keep logs for retain time, don't delete)
>
> backup database
> keep until time='sysdate+$RETAIN' logs
> format '%d_DB_%t_%s_%p_%T' tag '$DB $DAY $DESC';
>
> $RETAIN may be 1095(365*3).
>
> If the archive backup gets to the log first, the database backup does
> not find it. If the database backup gets to it first, then there are two
> copies in the catalog (and on tape).
>
> 3) When the expire job runs, how do we know which logs to expire? After
> the end of year one, we need to keep the ones needed for the annual
> restore for year 3, but no other logs.
>
> Do you use KEEP UNTIL?
> Do you let it go forever, but then run expire jobs?
> Are we completely off base?
>
> Is there a web page I should go to to find information (if OTN, please
> include search criteria, as I get too many hits, or none, depending on
> my selection criteria)?

Not trying to be too cynical, (since I've been in many similar situations) but try to convince management that they can

1. spend $n having you frig around for hours on end coming with up strategies to accomodate archive logs, backups etc, and have a medium level of confidence on recoverability
2. spend the same $n on some cheap, slow but large disks for a backup staging area. Then they will very good confidence in recoverability

hth
connor

-- 
Connor McDonald
Co-author: "Mastering Oracle PL/SQL - Practical Solutions"
Co-author: "Oracle Insight - Tales of the OakTable"

web: http://www.oracledba.co.uk
web: http://www.oaktable.net
email: connor_mcdonald_at_yahoo.com


"Semper in excremento, sole profundum qui variat."

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