[rescue] Tape Backup

[Sheldon T. Hall]

"Patrick Giagnocavo +1.717.201.3366" <patrick at zill.net> writes ...

> On Mon, Sep 16, 2002 at 08:14:06PM -0400, Sheldon T. Hall wrote:
>> Anyone got a "some other drive" I could rescue cheaply?
>
> I would recommend looking into a CDRW drive along with a "scratch
> disk" that will serve to hold your disk dumps.  As well, use a tool
> like freeveracity or md5 or something to compute checksums for the
> data before it is written to CDR and after it has been written to CDR.

That's a very attractive idea, and, as it happens, I just took delivery of a
new Imation (Plexstor OEM) SCSI CDR drive.  I've also installed cdrecord on
my SGI box.  The cdrecord doco is a bit opaque, though, and the one example
I tried from the man page (the two-command example of how to copy an audio
CD) failed when reading the audio CD.

Of course, the SGI seems to have another problem in this regard, as IRIX's
CD player application won't play CDs, either, regardless of the CD-ROM drive
I use.  I haven't had time to chase down the problems.

If you have any idea about neat-o backup scripts using cdrecord, I'm all
ears.

> If you have data useful to a business, you may wish to save it in a
> format that can be read by something other than a Sun, unless you
> always have a Sun around.  ISO9660 with filename extensions (to give
> you long filenames) is supported by pretty much all CD recording sw,
> and definitely on the Unix stuff.
>
> Actually what I mean to say is that you may want to be able to access
> just one file rather than having to wade through an entire dump.

Yes, that would be articularly useful for the backups of my wife's stuff.
The originals are on her Windows machine, and get copied over automatically
to her directory on the Solaris machine periodically.  Then I back it up to
tape.  A bit of "Tinkers-to-Evers-to-Chance" but it works and provides some
redundancy.  The problem is that the amount of data in the relevant file
system is about to outgrow the size of the backup tapes, and making
multi-tape backups of a single filesystem seems another potential problem
area.

And, yes, I'd much rather be able to back things up file-by-file.  Both
because we could read the resulting CD on another machine, and because my
most recent dump restoration experience shows me that it's a real PITA to
find and restore individual files even if the fscking tape can be read.

> CDR media only holds 650-700MB, but will be just as reliable holding
> compressed data as uncompressed data, giving you almost the same
> capacity as your current setup.  And CDR's can be had very very
> cheaply if you buy in bulk.

I can compress the stuff as part of the Windows-to-Unix backup procedure,
which would save disk space on the Solaris box as well as on the backup
media.

Great plan.  Now I just need a few clues on how to make cdrecord work!

Thanks.

-Shel
--
Sheldon T. Hall
shel at cmhc.com
206-780-7971