In article <20071210212934.GA21590@lonestar.cactus.com>,
Jeff Hyman <scolist@cactus.com> wrote:
>mvsguy typed (on Mon, Dec 10, 2007 at 12:49:51PM -0800):
>| I'm having trouble finding documentation for SCO UW. Can anyone point
>| me to a good resource so I can RTFM?
>|
>| My goal is to come up with a disaster recovery script and to test it.
>| At this point, we have no backup/restore software and do not have a
>| budget for any.
>|
>| How do I back up our system using the native SCO UX commands?
>|
>| Regards,
>| Way out of my comfort zone
>
> Whats your time worth? Disaster Recovery is not a fun time.
>There are 3rd party products out there that will make life
>a lot easier for you. There are some folks that think they
>are a waste of time and money, when you can roll-your-own.
>Thats all true till you lose data, have a hard drive crash,
>have data stolen, the list goes on.
>
> My hats off to you for awareness of the potential problems.
>When evaluating what your data is worth, a good reliable
>time-tested backup and crash recovery product should be reconsidered.
>They really are not that expensive considering their benefits.
>
>www.microlite.com [ BackupEDGE ]
>www.veritas.com
>www.cactus.com [ LONE-TAR ]
>
>- Jeff H
> Disclosure: I'm the LONE-TAR guy, and still recommend any
> 3rd party solution over what comes with the OS.
>

To echo Jeff's comments I had this scenario a few years ago.

I was called into a strange system, and prior to making
modifications I made a tape backup. Then, as I always do, I
checked to see if the backup was readable.

It was NOT.

Upon checking I found the tape drive was so dirty it would not
read anything.

After about 15 cotton swabs and alcohol the swabs started looking
clean.

I then insisted they get one of the commercial backup programs - at
that time it was split evenly between Backup-Edge and Lone-Tar

They thought it was expensive but I insisted.

A few months later they moved to a newer building and a newer
machine, and I transfered everything over.

Then the new machine started having failures. This was in the
early '386 days when memory card often had external cables to keep
the speed up instead of using the ISA bus.

Being able to load and start restoring the complete backup tape
after loading only 2 floppies - so the restore was starting in
under 5 minutes impressed the client.

He was even more impressed when I had to do it two more times that
evening - finally tracing the problems to the SCSI controller that
was mounted underneath the motherboard - some really strange
Italian design IMO [and saying that the older users know exactly
what 3 letter brand was on that machine].

Without the bootable floppies that contained all the drivers
for SCSI, Serial, etc. you would have had to install the OS,
configure the tape drives, configure the terminals or network
devices, etc.

So instead of going home at 3 or 4AM - we were both out of there
by 1030pm [we started at the close of the business day].

My charges >IF< he had not had the backup utilities would have
paid for the backup programs at least twice over.

That night the client became a true-believer and came to realize
that a good backup program does not cost, it pays.

If you decide to 'roll-your-own' and to make sure the backups are
truly reliable then you will probably spend more $$ of your time
than the program cost - unless you are paid less than a McDonalds'
employee.

Be aware the commercial programs perform bit-level compares on
the backup tapes/disks so that you KNOW the backup matches the
original exactly.

Be aware that just running checksums on backup media will NOT
guarantee that you have an accurate backup.

Though it is rare, if the data leaves the drive and gets corrupted
on the way to the tape controller the tape drive will write a
checksum which includes THE ERROR in checksum. So IOW all you have
done is verified vis the checksum that the data matches that
which was received by the controller and is not guaranteed to match
the disk.

So you need to evaluate the cost of your time for constructing
a backup program/script, the cost of potential data recovery costs
- or hiring an expert for handling things beyond your expertise -
versus the cost of lost data.

One of my first experiences with commercial backups goes back
to 1986 when Maynard used the TEAC [I believe that was the OEM]
data cassette and using Backup-Edge [though I think it had a
different name them]

There were two external tape drives and these were rotated on
schedule between 11 Xenix machines at the site.

Worked flawlessly except for the time on a Monday I restored
a Friday tape and NOTHING WORKED.

Unbeknownst to me, that office started shutting down early on
Friday, so they only backed up Monday thru Thursday, and the Friday
tape actually was about 1.5 years old and was for a machine
configuration far different that in use now.

I'd recommend seriously considering whether the cost of a
commercial backup will be that expensive in the event of a real
system crash, and the amount of downtime.

Remember that down time cost increases with the number of users
on a system. 100 users down for an hour could be thought of
as [approx] 100x $20/hr - or $2000 hour.

Bill
--
Bill Vermillion - bv @ wjv . com