OT Iomega Ditto Tape Backup

According to Ken Sterling :

I use 8mm Exabyte Mammoth tapes in a jukebox which changes to a new tape every night and does a backup. But that is on a unix system, not Windows. Iomega tends to be focused on Windows systems, and I'm not even sure how much the drives can hold, let alone the availability of a jukebox for them.

The Exabyte Mammoth drives which I am currently using hold 20 GB per tape, and the ones which I am switching over to (Mammoth II) handle

60 GB per tape, without compression. Add compression (and the right mix of files to be backed up) and you can get 150 GB per tape. :-)

Not I -- but I had to answer your question of whether anyone still uses tapes for backups.

Good Luck, DoN.

The Iomega SCSI Zip and Jaz drives work perfectly on a Solaris SPARC system. I've used both in the past but only use Zip now. Just plug and play.

Best wishes,

Chris

Well ... they weren't always plug-and-play in Solaris SPARC systems. For Solaris 2.6 I had to write my own entry to add to /etc/format.dat so I could put a unix filesystem on them. (Yes, I could mount the MS-DOS filesystem, which was enough for some purposes, but not for others. Solaris 10 has two Zip entries -- one for the 100 MB version, and the other for a 250 MB version

But Zip is only 100 MB (apparently now also 250 MB) -- still not enough to be worth the trouble. For what I would use those for, I would prefer to use a USB thumb drive or two. (E.G. moving files between the unix boxen and the token Windows box.)

What is the capacity of the Jaz drive? Probably still not anywhere near the Mammoth 8mm tapes. O.K. A quick Google seems to suggest that they are a choice of 1GB of 2GB -- again no better than the thumb drives. :-)

Better (for me, at least) to use burnable DVD-ROMs for permanent backups, and thumb drives or the net for transfers between systems.

Enjoy, DoN.

I use rdiff-backup for making incremental remote backups. It is an amazing piece of software. Works perfectly for me. I backup stuff on other computers at home, and also on a remote computer for off site backups.

i

According to Ignoramus24595 :

Try "amanda" for serious automated backups. I've got it controlling an Exabyte EZ-17 jukebox with a Mammoth-1 drive (seven tapes, one drive) in it at present, and am about to move to an Exabyte EXB-430 (30 tapes, possible maximum of 4 drives, though I only have two installed at present).

The software is free source from the University of Maryland, and now comes with Sun's Solaris 10, and in the pre-compiled packages on OpenBSD, so it should also be workable on linux systems as well. (But it is not difficult to compile -- I compiled my first version of it from downloaded source.

It can do very extensive backups over the net, though I happen to run it on the file server, so everything which I *really* need to back up is already present there.

At present, I only have to read the e-mails about the status of the backups daily, and once every six days, swap out one magazine for the next (of three). Every six days, instead of seven, because there is a cleaning tape in the 7th slot of each magazine.

Once I switch to the EXB-430, I won't have to do anything other than read the status emails -- unless a tape goes bad, at which point I swap in another tape and continue. It is even set up so it caches what

*should* have gone to the tapes, so you can flush it to the next tape at need in case of a tape failure.

Enjoy, DoN.

Some DVD makes and models are archival, some are not. Archival costs more, but are expected to last 100 years (based on accelerated tests, so nobody really knows). There is a fellow (whose name escapes me) who tests CD and DVD longevity, and publishes his results on the web somewhere.

A bigger problem is when a format goes obsolete, and readers can no longer be bought, and what few readers still physically work are no longer supported (old drivers don't work on new operating system versions).

What I've always done is copy everything onto the newest format/device. Given the rapid rate of improvement in storage media, the old stuff always takes a small fraction of the capacity of the new system.

Joe Gwinn

In this case, tape is worse than DVD, because at least DVD IS a standard. The beauty of computer standards is there are so many to choose from. DVD, being MORE than a computer standard has some chance of surviving.

You say you had your backup on Travan 2 tape? And the computer got stolen, or destroyed? Good luck buying a new drive to read it. And many tape formats are even harder to find supporting drives. Also, a tape CAN be corrupted just by dropping it. Or setting it on top of your monitor (or beside, or under). Or in a cuppord next to a high power cable - any number of ways. A good DVD recordable (not re-writeable) is relaively secure if stored with any care.

According to :

[ ... ]

Note that this may depend on what format was *used*. There are standards, such as "tar" (Tape ARchiver) from the unix world which have been ported to many other systems. Generally, any tar format is at least backwards compatible so newer systems can read older files.

And the problems of drivers specific to the OS -- with SCSI tapes, CD-ROMs, DVD-ROMs and such -- and even with IDE interfaces through bridge cards available from Acard -- pretty much any drive can be used to read data on unix systems. Windows has the nasty habit of requiring a separate driver for each device based on a common chipset, rather than providing generic drivers which can operate any device of that chipset. The open source unix systems generally write drivers for any chipset for which sufficient documentation is available. (Some vendors tend to keep the interface documentation secret, locking you in to their drivers -- and these are good ones to avoid for anything archival in nature.

I'm actually using one of the Acard bridge cards to use an IDE DVD burner in my SCSI Sun Workstations. Even *with* the cost of the Acard, it is a lot cheaper than getting a SCSI DVD-writer -- even if you can find one. :-)

Once you get to old enough things -- such as punched card readers, these predate standards such as SCSI (or even SASI -- the precursor to SCSI). However, punched cards are so low in density so they are highly undesirable -- except that if necessary, a human can read the cards, as long as he knows which encoding was used. (There were several charactersets, as well as binary cards -- and even the keypunches which typed the characters along the top edge of the card may not be sufficient information, as often they were used to punch cards for a machine which put a different interpretation on a given pattern.

8-level punched tape was usually ASCII, and this can be read by a trained human as well - but it is slow and error prone. And for machine controllers and other things there were alternate codes, including an 8-bit translation of EBCDIC such as was found on the old Frieden Flexowriter (one of several encodings which they used).

There is that -- though there may be an argument for holding onto at least the previous version, just in case the new device goes obsolete before the older one does. :-)

Also -- beware of things which can change characters in the process of reading in and saving. An example is Microsoft Word (and many other word processor formats), which tends to replace "'" and "`" characters with alternate versions from extended ASCII sets. These show up often enough in usenet postings to show how much of a problem this can be.

Well -- if you trusted your data to something using a proprietary format -- you are just plain stuck. If, however, you got drives which followed standards, and used open standards programs (like tar) to write them, you have a pretty good chance of being able to recover it using other drives which follow the same standard.

Or storing in an automobile during the summer. I used to maintain a membership database for a local organization, and I made it as standard practice to put copies of the most recent backups in the hands of the secretary or the president of the organization. Once, I got them back (8" floppies, FWIW) after a two-month residence in the hidden "trunk" compartment of a station wagon (estate car for the UK readers, I believe). The jackets had shrunk and bulged out in the middle like some puff pastry. As an experiment, I sliced the jackets open, and transferred the raw disks to a jacket which had held a bad floppy -- and the floppies were totally readable -- but I would not have bet on that. :-)

Agreed.

And stick with things with standardized interfaces and open standard formats, SCSI and tar are good examples.

Enjoy, DoN.

Thanks for the info, I did some looking and turned up the following links

My Verbatim disks are DVD+R and made by Mitsubishi so listed as 1st grade media in the 2nd link and so should be good for archival purposes as DVD+R rather than DVD-R. When I have used the current lot I shall look at getting those said to be the best.

Interestingly the DVD videos I have which are all corrupted, 4 disks in total, are duplicates as I have 2 copies of the same 2 disk set of the same vintage. The check of the maker ID showed the following

1st DVD set, set 1 2 x RITEK R03 DVD+R (2nd class media, notes: degradation concerns), DVD+R better than -R from 1st sited article but poorer media.

1st DVD set, set 2

1 x TYG02 DVD-R (1st class media), 1x PRODISCF01 DVD-R (2nd class media),

So a mixed bag but interesting to see all show corruption to varying degrees even after 2 years and interesting that the same apparent DVD release was done on DVD-R and DVD+R. To my knowledge I keep the DVDs correctly, ie in their plastic case out of direct sunlight and in cool dry conditions.

I think in the next few days I shall run some of the disk checking routines on the corrupted DVDs to see what else may be shown.