Re: Recovery using RAW devices

In article <3qehm0$72r_at_horus.mch.sni.de>, Jan-Peter Meyer <jan-peter.meyer_at_scg.de> wrote:
>lou2_at_cbnews.cb.att.com (louis.avrami..jr) wrote:
>>
>> In article <3q03sa$5k2_at_hpcc48.corp.hp.com>,
>> Contractor - Yuktton "Jonny" Chan <jychan_at_corp.hp.com> wrote:
>> >Jean-Francois Denis (jean-francois.denis_at_s1.bru1.sni.be) wrote:
>> >
>> >: We are using Oracle 7.0.15 DBMS on a UNIX machine. For performance
 reason, we
>> >: will use RAW devices instead of UNIX files.
>> >: We worry about the recovery after an Oracle crash when using RAW devices.
 

>> >: Could you give us any hint or mention the problems you met using
>> > RAW devices.
>> >
>> >: Thank you for your help.
 

>> >: Jean-Francois DENIS (jean-francois.denis_at_s1.bru1.sni.be)
>> >: Siemens-Nixdorf Belgium
>> >
>> >we implemented an Oracle DB using raw devices on a Sequent and have
>> > performed
>> >complete db recovery twice from a hot backup without any problems.
>> >we use
>> >are a backup package solution from Alexandria to do the backups.
>> >
>> >Johnny Chan
>> >Indepedent Oracle Specialist
>>
>> Most versions of UNIX now have "volcopy" or something similar. It copies
>> raw devices to tape much faster than other UNIX archiving utilities such
>> as cpio or tar.
>>
>> Lou Avrami ( attmail!lavrami )
>
>Tar and cpio won't work with raw devices. You have to use dd in order
>to backup the database files.
>Another way is to make a Full Oracle backup. It will read the
>raw devices through Oracle and write it whereever you want it.
>
>Jan-Peter Meyer
>jan-peter.meyer_at_scg.de
>

Jan-Peter,

        Thanks for catching my faux-pas. Yes, dd is what you'd use to copy a raw device to tape.

        At my site, we're able to volcopy approximately 5 Gigs of raw disk devices and cpio about 1 Gig of UNIX file systems in about 2 hours, on an NCR 3555 running UNIX System V Release 4, with 2 Exabyte tape drives.

Lou Avrami ( attmail!lavrami ) Received on Mon Jun 19 1995 - 00:00:00 CEST