Re: Compress datafiles for backup
Date: 1996/04/21
Message-ID: <Dq7K68.IK2_at_cix.compulink.co.uk>#1/1
> My oracle database is 8GB. Tape capacity is 4GB. I have no support to
> change tapes at night during daily cron job for cold back.
>
> In order to fit all the data files on one single tape, I would like to
>
> back up as :
>
> tar -cvf - list_of_files_to_be_backed_up | compress > /dev/rmt/0m
>
> and recover as :
>
> uncompress < /dev/rmt/0m | tar -xvf - list_of_files_to_be_retrieved
>
> I am on Hp-Ux 10 and Oracle database 7.2.3.
>
> Any body sees any obvious problems in this ? Only worried because I
> have not heard anybody compressing files to tape. Note that this is
> for COLD BACKUP ONLY.
There shouldn't be a problem with this *IF* compress handles "empty" files correctly. That is to say File a.dbf= 1000000 bytes and contains no data or at least doesn't contain 1000000 bytes of data. If
compress a.dbf; uncompress a.dbf.Z
leaves you with a file 1000000 bytes big then everything should be OK. Obviously you should run a test before committing yourself to this method. One other thing, you might want to try getting hold of a copy of gzip which, especially with the "-9" option will compress much better than compress. Sadly I don't have a copy for your platform. Just replace calls to compress with calls to gzip -9.
I hope this help.
These are *my* opinions. Please don't make the mistake of believing anybody else is stupid enough to think like this!
Stuart Hemming | shemminga_at_cix.compulink.co.uk The Data Base | Tel: + 44 (0) 115 925 0005 Nottingham UK | Fax: + 44 (0) 115 929 4668 -------------------------------------------------------------------Received on Sun Apr 21 1996 - 00:00:00 CEST