Safe longterm storage

[Ripplinger]

I save a lot of old programs on DVDs and have never had one fail yet, and I have quite a few that are almost 20 years old now. I think the main thing there is to make sure you always use good quality discs and to burn at slower speeds. I only use Verbatim and never burn higher than 4x, sometimes even at 2.4x. This site has great info regarding DVD quality.

For ebooks, documents, images and certain other files, I back those up nightly to the 2nd drive in my computer and to a 2nd PC, and that 2nd PC backs up to its 2nd drive. And in the case of ebooks, I also back those up to my netbook and to the cloud periodically for when I might be traveling and have to do a factory reset of my reader, so I won't be stuck without reading material. So I think having my full library in 6 locations has me covered. The joy of ebooks being so small in file size!

[Greg Anos]

Here is what I do.

All data on external drives.
One set as user drives.
One set as back ups.
One set as off-site back ups.
The most important data is on flash cards, as well, in my "bugout" (travel) bag.

A spare drive for drive copying during rotataion.

I figure I'm more likely to lose me than my data....

[saoir]

I use Time Machine which is excellent. I also run a SuperDuper! every week. In addition I split my most important data - stuff that actually matters, between Dropbox and Jotta. I feel pretty secure.

[Ghitulescu]

Originally Posted by pidgeon92

I recall reading years ago that flash memory had a limited number of rewrites. Is this no longer the case?

Everything has a limited number of rewritings.
When they arrived at computers, the HDDs could bear between 5000 and 20000 writings per sector, something like today's Flash-drives (SSDs). I was very careful back then to use the RAM rather than the HDD in transferring a diskette to another . A CDRW can be in theory erased 500 times (some claim 1000) but I know no CDRW that broke the two digits barrier .

The point is that storage items are not made to be rewritten. Working memories are made for this. Storage media is generally WORM (write once read many), although tapes, a staple media, can be rewritten.

PS: I would be more worry about the charge-discharge cycles of the battery inside the eReader, in particular when no replacement is foreseen.

[saoir]

Originally Posted by j.p.s

I'm pretty sure bad blocks would start to develop during the first month of overwriting the entire device once per day.

It doesn't matter if they do. The software identifies those blocks dynamically and maps them to be avoided.

[j.p.s]

Originally Posted by murg

Don't worry about it.

You'd have to overwrite the entire device every day for your entire lifetime, your kids entire lifetimes, and their kids entire life times to run into the write cycle limit.

Originally Posted by j.p.s

I'm pretty sure bad blocks would start to develop during the first month of overwriting the entire device once per day.

Originally Posted by saoir

It doesn't matter if they do. The software identifies those blocks dynamically and maps them to be avoided.

But it does matter.

The write cycle limit specifies the number of rewrites before some percentage of the total number of blocks is bad, not before any block is bad. So it becomes a problem to rewrite the entire device not only after grandchildren's lifetime, but well before the end of a year of daily rewriting the entire device.

Last year, I wrote a 16GBish disk image to a new blank "16GB" SD card. I booted from this card a couple of times and made some configuration changes that I could not figure how to back out, so I decided to just reimage the card. When I tried to do so, I got a "device full" error message before the copy was complete. So, not even a single complete rewrite of the entire device in that particular case.

[Katsunami]

Bad SD-card.

I have SD-cards in use that are at least 5 years old, and one USB stick will hit 8 years somewhere in 2015.

[hardcastle]

If I was getting really serious about this, I'd set up a 4-drive RAID array in a small, low powered server. I'd set the computer up to turn on and check its hard drives yearly, and make a sound if something went badly. Not connected to internet or anything, well grounded, etc.

[j.p.s]

Originally Posted by Katsunami

Bad SD-card.

I have SD-cards in use that are at least 5 years old, and one USB stick will hit 8 years somewhere in 2015.

Are they full and how often are they completely rewritten?

Nowhere did I write that a typical card would fail on the first rewrite, but I bet that number is much much closer to 1 than the number of days in three generations.

[Katsunami]

Originally Posted by j.p.s

Are they full and how often are they completely rewritten?

Yes. They are the SD-cards for my camera. They've been shot full of images and formatted regularly (somtimes multiple times per week).

The USB stick is a Sandisk Cruzer 8GB; the older metal capless version. It has experienced and survived everything a USB stick can possibly experience in normal day to day use, for 7.5 years already.