mirror-textfiles.com/messages/TBFILES/tpbackup.txt

@MSGID: 1:202/354.0 30a8f480
  CS> 1) How long do you need to retain the backups?  Not all
 CS>    backup media will hold data for the same length of time.
 CS>    Magnetic media usually degrades much faster than optical
 CS>    media, for instance.

 WL> Most of my data backups will be what I'd consider
 WL> short term. Maybe a couple months, then I'd be cycling
 WL> back through the same media with new information.

Magnetic media is OK, then.  Tapes are generally the cheapest way to go and
should be OK for your needs.

 CS> 2) How many backups sets do you need for safety?  It is usually
 CS>    a bad idea to have only one backup set considering how you
 CS>    would have to destroy it in the process of reusing the media
 CS>    for the next backup.  And backup sets can turn out to be
 CS>    unrecoverable for various reasons, so it is good to have
 CS>    at least a few sets.

 WL> At the moment, my only backup system is copying to my
 WL> other harddrive the most important data. REALLY bad
 WL> idea to run a system like mine with no backups, but as
 WL> I used to have a 40 meg drive when I started, and now
 WL> have almost a gig, floppies don't work very well
 WL> anymore. =

I gave up on floppies somewhere around 300MB of files to
back up.  I used an Irwin QIC-80 tape drive for a year or
so, but it got to be a drag because even though it was
advertised as getting 250MB per tape compressed the
compression was never that good and realistically
180MB per tape was about the most I ever saw.  After
it started taking 3 tapes to back up, I sold that
hardware and bought a DAT drive that gets 2GB per tape
without compression.

 WL> I would be fine with two sets of full backups.

So the media cost might not be critical for you.  QIC
tape drives become an option, then, whereas if you
needs lots of tape then 4mm DAT and 8mm drives are
far better choices even though the drives cost more.

 CS> 3) How much storage do you have to back up?
 CS>    Also consider how much storage you might add during
 CS>    the expected life of your backup system.

 WL> As I mentioned above, I have about 1 gig of storage,
 WL> but I'm only actually using about 600 megs of it at
 WL> the moment. I probably could very well add another gig
 WL> or two, easily, before I wanted to get a different
 WL> backup system.

 WL> For _ANY_ media, that could get costly.

Actually, not really.  For $8 or so you could buy a DDS-1 90m DAT tape that
would hold 2GB uncompressed and around 3-4GB compressed with a realistic
compression ratio.

 CS> 4) How much downtime can you afford during backups?
 CS>    If you don't care, then a slower backup system
 CS>    may help you save money.  If you do care, a faster
 CS>    backup system may be worth the extra expense.

 WL> Well, ideally, I'd like to run it in the background
 WL> (which also means I'd need something that works with
 WL> OS/2 ;) so even if it takes 17 hours, it shouldn't be
 WL> a big deal.

Running in the background has drawbacks, however, as it is
a good idea to do a verify pass after any backup and with
a multitasking system that is changing files after they
have been backed up but before they are verified, you
will get a lot of verify errors but you may not be sure if they are a real
problem or just because a file was changed.

 CS> 5) How much human intervention are you willing to tolerate
 CS>    during backups?  Media swapping takes some time and attention
 CS>    and can prevent backups from being totally automatic, so
 CS>    paying more up front for extra capacity or for an automatic
 CS>    media changer may be worthwhile.

 WL> I could swap something as small as 20 meg tapes, if I

Swapping tapes is worse than swapping floppies.  Generally it takes several
seconds to a minute to start using a new tape, whereas swapping floppies takes
much less time before the backup system is actually writing data to the media.
I absolutely wouldn't mess with any tape drive that uses tapes smaller than
120MB uncompressed.

 WL> had to. I will NOT swap 1.44 meg floppies. <g> I'd
 WL> like to just plug in two or three media sets and be
 WL> done with it, but I can live with more. It's not time
 WL> critical for backups, really, as long as I do have a
 WL> good set of my -last- backups already avalible.

 WL> Depending on cost, a media changer may be worthwhile
 WL> anyway--but I am looking for technology for which
 WL> support will exist for a while. Hopefully nothing
 WL> that's quick, fast, and completely proprietary (unless
 WL> the company has really good support for it. <g>)

As far as media changers go, DAT changers are generally the cheapest but you
are still looking at $2000+ for such a drive.  Fortunately,you don't really
need that capacity.  A single DDS-1 tape is more than enough for now and a
DDS-2 tape would get you 4GB uncompressed if you're willing to spend twice as
much for the tapes and about $100 more for the drive.

 CS> 6) Do you have media interchange requirements, such as being able
 CS>    to send backup media to other offices or customers or service
 CS>    bureaus?  Not all backup media are widely used, and some are
 CS>    proprietary to a single company.

 WL> No, I'd just be using it for my home system. My home system also
 WL> includes my business software and data, but it's all
 WL> on the same hard drives. _I_ am my business,
 WL> basically, so I don't really have any other offices to
 WL> which to need to send data. (Although, hey, that would
 WL> be cool! :)

 WL> However, I may be setting up another system here soon,
 WL> so it would be nice to have something external . . .
 WL> but I'm also looking at cost.

You can put pretty much any SCSI backup device in an external case that has its
own power supply for under $100.  You'll
also need cables and a terminator, and those could run another $50 or so
depending on what type of cable you need.

 CS> 7) How much are you willing to spend?  Backup systems span a wide
 CS>    range of prices, from roughly from $100 to $10,000 for a PC
 CS>    backup system.

 WL> I'm willing to pay a little above the "going rate" for backup systems,
 WL> as I would like to have my backup system expandable
 WL> (at least a little), but then again, I really don't
 WL> need anything complex, either. :)

 WL> Well, my answers may be a little vague. I appologize for that, but I'm
 WL> afraid I'm not EXACTLY sure what I'm looking for,
 WL> myself. :) I'm still looking for ideas at this point
 WL> in time, I'm not quite ready to just run out and
 WL> purchace.

Have you had any new thoughts about your backup needs in the last few weeks?

 CS> For example, Conner has a tape drive on the market (TMS-4000?) that
 CS> uses the new wide QIC cartridges that store 2GB native and 4GB
 CS> compressed (assuming it really does get 2:1
 CS> compression which depends
 CS> a lot upon the data being backup up) and operates around 27MB per
 CS> minute native speed with both SCSI and IDE/ATAPI versions available.

 WL> Well, now THIS is something I have not heard about. :) I guess with all
 WL> the DEC tape equipment I'm familiar with playing
 WL> around with at work, and all the cheap Colorado drives
 WL> that tote themselves off as 250 megs (but they are
 WL> only 125, they just use compression), I thought that
 WL> tapes were generally going to be slow, awkward and
 WL> very abundant for large amounts of data. :)

You're thinking of dirt cheap QIC drives.  Most of these attach via floppy
interfaces.  I would avoid these. they are slow,don't have hardware data
compression, and are error-prone
on multitasking systems.

 CS> DAT drives are another option, but for $400-600 you can usually only
 CS> get refurbished DDS-1 drives.  A brand new DDS-2 drive will probably
 CS> cost around $800-1200, depending on the manufactuer.  The HP C1533A
 CS> drive, for instance, is generally around $1000-1100 and provides 4GB
 CS> native capacity with backup speeds in the range of twice as fast as
 CS> the Conner TMS-4000 drive I mentioned above.  Tapes are cheaper, in

 WL> How well (if you know) are these drives supported by
 WL> OS/2 and OS/2 backup software? (That's probably what
 WL> I'm going to be dealing with the most).

The Conner TMS-4000 drives are supported by BackAgain/2 Pro. I recently bought
that backup software and it seems pretty nice as it's got support for basically
all SCSI-2 tape drives and many older SCSI-1 drives also plus support for
backup to a
network and to any other media that supports an OS/2 file
system.  Optical drives are supported, for instance, and
Iomega ZIP drives should work OK, also.  So far I've just
been using BackAgain/2 Pro with the Archive 4324RP DAT
drive I've had since mid-1993.

 CS> possible to buy ISO standard 1.3GB optical drives (which use two
 CS> sided cartridges taht get 650MB per side but must be flipped
 CS> manually) for as little as $595 via an outfit called Corporate
 CS> Systems Center. If you want a brand name new drive that uses ISO
 CS> 1.2GB and 1.3GB media, you're probably looking at $1000-2500. Media
 CS> costs are around $70-90 per 1.2GB or 1.3GB
 CS> cartridge.  You may not be
 CS> able to use 1.3GB cartridges as they use 1024 byte sectors which are
 CS> not supported very widely on PC clone systems, so you might have to
 CS> use the 1.2GB cartridges that employ 512 byte sectors. A solution

 WL> This is a bit pricey . . . but, besides being more
 WL> long term and random access (and those are good points
 WL> straight off), are there any other advantages that
 WL> might make it worth the extra investment? Perhaps the
 WL> speed? I'm wholy unfamiliar with most optical drives.

Optical drives generally are going to be a few times faster than tape drives,
but again it depends on the drives you
are comparing.

 CS> most.  ISO 1.2GB and 1.3GB optical formats are also widely used at
 CS> this point, so data interchange possibilities are fairly good.

 WL> Now, this might be something to think about for my
 WL> system at work . . . being as there, I'm on their
 WL> budget. ;) And the backups we make there are general
 WL> pretty permenant. (Data dumped from various
 WL> intruments, such as our weather server or the radio
 WL> telescopes...)

Optical disk is basically the best choice for long-term backups.

 CS> drives and roughly 2-3 times faster than many other optical drives.
 CS> The list price for an Apex drive is $1695 and the media costs about
 CS> $150-200 per cartridge.  A backup system like this would be good for
 CS> long retention life, high capacities, and where the need for data
 CS> interchange isn't high given that it is very new and the media isn't
 CS> an ISO standard.

 WL> I tend to like to grab stuff once it's standard (even
 WL> if that standard is de facto ;) -- I've had some bad
 WL> scrapes with some non-standard hardware that looked
 WL> like it was the next generation, but turned out to be
 WL> nothing. :(

Pinnacle Micro seems to be a fairly solid company and has been doing really
well in the optical drive business.  I think I saw a Megahaud ad in PC Magazine
that listed Pinnacle Apex 4.6GB drives for around $1400-1500.


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