
Newly recovered Ground Zero photos show why you should back up your CD-Rs now - Tomte
https://www.theverge.com/2019/6/16/18678447/9-11-ground-zero-world-trade-center-pictures-recovered
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llao
Direct link to the source:
[https://twitter.com/textfiles/status/1138537238537625601](https://twitter.com/textfiles/status/1138537238537625601)

Direct link to the images:
[https://www.flickr.com/photos/textfiles/albums/7215770899728...](https://www.flickr.com/photos/textfiles/albums/72157708997281912)

And what a title! The photos do not show the need, but the need is shown by
some of the CD-Rs on which the photos are stored being faulty. Ground Zero
refers to 9/11 here, not the nuclear bombing of Japan in WW2.

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rlv-dan
My most popular blog post is a test I made, reading 400 CDR:s of backed up
data. Most interesting is people discussing their own strategies in the
lengthy comments.

[https://www.rlvision.com/blog/how-long-do-writable-cddvd-
las...](https://www.rlvision.com/blog/how-long-do-writable-cddvd-
last-400-discs-put-to-the-test/)

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dvd-guy
Anecdotal evidence, but I've recently gone through my ancient CD collection
(in so doing, I found Ubuntu 6.04 installers, AOL dial-up CDs and other
relics) and archived them with GNU DDrescue. It had no problem reading all bar
a handful of CDs from the mid-to-late 90s and early 00's - the failure rate
was much lower than I expected. The failures were mostly completely visually
identifiable too - the layers had started to separate.

I've also been backing up personal photos to DVD annually for quite a few
years. Each disc contains encrypted Duplicity files, and a PAR2 archive to
assist with any deep failures of the on-medium parity. I also usually include
a disk or two of pure parity archives, to handle a total failure of any disk
or two in the middle.

Each year I check the price of DVD vs. Blu-ray and when factoring in the cost
of the burner DVD seems to stay _just_ on top for $/GB. It doesn't help that
I've still got spare DVDs lying around, and people basically give away the
blanks these days.

This is not my only backup strategy, but it is the only one that is cold,
read-only, and offline.

~~~
mehrdadn
> Each year I check the price of DVD vs. Blu-ray and when factoring in the
> cost of the burner DVD seems to stay just on top for $/GB. It doesn't help
> that I've still got spare DVDs lying around, and people basically give away
> the blanks these days.

Cost is one thing, but does the capacity not bother you too? DVDs are so small
in comparison to BDs. Not to mention the time you have to waste switching
discs (or reading/writing them, if relevant).

~~~
dvd-guy
Burning tens of DVDs is a little tiresome, but it is well enough scripted that
it is easy to slowly swap them in and out while focusing on another task - the
brief interruption is barely noticed.

It also means that the failure of a whole disk has a lesser impact on the
whole.

Edit: that said, I do have a spindle of 100 CD-R that were given to me. I
haven't had the motivation to use them up yet.

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shellmayr
I wonder about this: how do people archive their information, especially photo
and video data. I use an array of mirrored HDDs in different locations with
everything on it, plus parts of it on a cloud hosting service. It isn't very
convenient though and it seems there should be a better solution. How do
people in here do it? Most solutions (for me) fall short on quick retrieval
and possibility to visually browse photos.

~~~
WalterBright
I buy new hard drives every year and copy all the data to them.

Edit: It's not just the longevity of the drive (though after 20 years they
often don't work at all). Drive interfaces change over time, and I have drives
where there is no way to hook them up to a newer computer, and my old
computers failed due to capacitor problems.

For example, good luck trying to read a 5.25" floppy. You'll need to build
your own hardware and write your own device driver to do it.

Just keep copying it all forward every year. Multi-terabyte hard drives are
cheap.

~~~
tialaramex
The philosophy of just copying data makes sense, but your justification not so
much.

> Drive interfaces change over time, and I have drives where there is no way
> to hook them up to a newer computer

20+ year old PC drives will have IDE interfaces, which you can of course get a
USB adaptor for very cheaply and I have several laying about. Really old PCs
or non-PC hardware (e.g. the Amstrad CPC 6128 in the 1980s had an after market
hard disk option) will need a different adaptor, but it's still just not that
hard, and certainly shouldn't be categorised as "there is no way".

> For example, good luck trying to read a 5.25" floppy. You'll need to build
> your own hardware and write your own device driver to do it.

You can easily buy refurbished 5.25" drives, and you can convert the data
signal (which for a PC was basically the same as for 3.5" drives, but with a
different physical connector) to USB. They're bulky and they need a lot of
power at 12 volts, which is probably why off-the-shelf 5.25" USB floppy drives
aren't a thing unlike for 3.5", but it won't require that you "build your own
hardware" in any real sense.

You're only going to need to go writing device drivers if you've got some
crazy disk format, and it'd have to be pretty crazy because the Catweasel
already covered a lot of that territory (a Catweasel was a thing for Amigans,
whose disks are a crazy format, to let them use PC disk drives to read their
disks years ago, the last ones have an FPGA in them so that the uploadable
firmware can decide how to control the drive).

~~~
WalterBright
I have several 5.25 drives laying around. The connectors still fit on them to
the motherboard, but the BIOS no longer recognizes them, though the BIOS will
recognize 3.5 floppy drives.

I can't find any device that connects the drive with the computer that doesn't
require writing a device driver.

It's not a crazy disk format, it's DOS format.

As for hard disk drive interfaces, I have a couple off the shelf USB
interfaces to IDE drives. The connectors fit, but they don't recognize the
older drives.

~~~
tialaramex
I can't speak to what's up with the BIOS versus 5.25" drives, beyond to say
that I'm confident somebody out there has this working without writing device
drivers.

For the USB to IDE thing, my guess would be that the USB interfaces you tried
want to do some newer incarnation of ATA than the drive supports and so they
can't communicate, at the extreme that could be LBA48 (48-bit logical block
addressing, which is from this century and so obviously isn't going to work on
say a 20 year old hard disk) but it could even be DMA, which was optional in
early ATA specifications and might have been skipped by cheap manufacturers
back in the day.

I don't think logical addressing itself was ever optional, but I guess it's
possible that a _really_ old IDE drive might not implement it and yet work
anyway in DOS which didn't originally use LBA mode. Doing CHS mode really
would be asking a lot, compared to PIO (the alternative to DMA) which really a
competent implementation of that USB adaptor ought to be able to do, slowly
like a real PC.

~~~
WalterBright
> I'm confident somebody out there has this working without writing device
> drivers.

I google search for it now and then, and come up with nothing that can be
simply installed and used.

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willtim
A huge shame. I backup my optical media to S3, but I also use M-DISC "mineral
discs" which hopefully will last much longer. Sadly they were not available
back then.

~~~
lloydde
Do you mind sharing your monthly S3 bill and it’s rate of change?

~~~
willtim
It's around 10 dollars, but then I have less than 1 TB. I recently starting
backing up my RAW files remotely, so this number is set to increase
significantly (!) I am very interested in S3 alternatives. I haven't looked at
the Amazon Glacier options either, but I suspect the retrieval times make it
awkward to query/verify backups.

~~~
lloydde
Thank you. My pleasure and problem is my spouse is a professional photographer
;)

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pmlnr
Archival grade blu-ray or mdisc, those should last surprisingly long. Even
normal blu-ray is ok, but the very cheap ones are not, those use organic dye.
The rest is usually ~5-8 years.

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Tepix
I use MDISC media for photos. I wonder what everyone's experiences are,
especially for the 25GB and 100GB Blu-Ray variants - have you seen them fail?
It'd be great if MDISC are indeed as great as they claim to be and I don't
have to worry about copying the stuff over to some other media for 50 years or
so.

PS: Yes, I have an external optical drive with USB 3.0 (and a USB A and USB C
cable) to go with the media to be able to read them later

~~~
lrem
My USB Blu-ray drive failed after two years and new ones cost about four times
more than they used to. I shrugged it off and added one more hard drive of
redundancy instead.

~~~
pmlnr
While hard drive lasts, the trouble of disk based storage lies in the
filesystem. I'd recommend running ZFS for long term storage.

~~~
mrguyorama
When do you predict Windows will no longer read FAT32? My first real computer
was Windows 95b and that formatted FAT32 disks, and even my current 7
installation reads and writes FAT32 on flash drives

~~~
pmlnr
I was referring to bit flips and data corruption. Mirrored zfs can correct
these, the rest of the filesystems can't.

Flash drives are terrible mediums for backups unless you power them every
month. When they loae charge they lose bits permanently.

~~~
mrguyorama
Do flash drives every "refresh" unmodified storage? I'm not super familiar
with the behavior of cheap flash storage controllers

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antocv
I just keep all my archives in zfs mirror disks, which I every 4 years buy 2
new of and copy them to there. The old ones are not deleted, just stored
offline.

Then I also have usb-memory sticks which I gave to family.

