topic Re: Backing up a raw device in Operating System - HP-UX

Backing up a raw device

Alan Casey — Fri, 06 Dec 2002 10:39:50 GMT

Hi,
Does anyone know any tools/software that can be used to backup a raw device to tape?

Re: Backing up a raw device

Jean-Louis Phelix — Fri, 06 Dec 2002 10:43:02 GMT

Hi,

Use the basic dd ...

dd if=rawdevice of=tape bs=512k

Regards.

Re: Backing up a raw device

Stefan Farrelly — Fri, 06 Dec 2002 10:44:40 GMT

The only tool you should use to do this is dd. eg; dd if=/dev/vgxx/rlvolyy of=/dev/rmt/Xm bs=1024k

You need a blocksize from 64-1024k for best performance.

Be wary though, dd does no error checking and is not guaranteed to work. In my experience it works fine but you should take precautions like reading the tape back using dd to check its all redable, and do multiple backups to be safe!

Re: Backing up a raw device

John Palmer — Fri, 06 Dec 2002 10:44:45 GMT

Hi,

dd is the tool, use a reasonably large blocksize and specify the character raw device file.

To backup...

dd if=/dev/vg??/rlvol? of=/dev/rmt/0mn bs=64k

and to restore...

dd if=/dev/tmt/0mn of=/dev/vg??/rlvol? bs=64k

You might want to experiment with various block sizes and pick the one that runs the quickest.

Regards,
John

Re: Backing up a raw device

Alan Casey — Fri, 06 Dec 2002 10:48:43 GMT

thanks guys,

I was hoping for something more advanced than the dd option as I need to backup many raw devices, and be able to restore them individually and quickly. I know Veritas NetBackup can do raw-partitions, but I was hoping for a HP option.

Re: Backing up a raw device

Stefan Farrelly — Fri, 06 Dec 2002 10:52:07 GMT

All High level backup solutions can also backup raw partitions;

Veritas Netbackup
Legato Networker
HP Omniback

so HP's Omniback is the high level backup software from HP.

Re: Backing up a raw device

Robert-Jan Goossens — Fri, 06 Dec 2002 10:54:20 GMT

Hi,

We use Legato-Networker.

Kind regards,

Robert-Jan.

ps. beleave veritas does have the option to use raw devices.