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Author Topic: Now we're talkin STORAGE  (Read 18896 times)
kaelaria
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« Reply #40 on: January 13, 2007, 12:09:42 AM »
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If you want the most secure solution, build a dedicated raid 5 array, and rebuild it with new discs every 5 years.  As they fail individually in between main builds, you lose nothing.

You can build a 1TB array with external cabinet for less than $750 right now, and that will only be cheaper in the future.  

Big deal.

I run a 1TB raid 5 array in my system right now, and it cost me $600 in drives.
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feppe
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« Reply #41 on: January 13, 2007, 12:21:59 AM »
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If you want the most secure solution, build a dedicated raid 5 array, and rebuild it with new discs every 5 years.  As they fail individually in between main builds, you lose nothing.

You can build a 1TB array with external cabinet for less than $750 right now, and that will only be cheaper in the future. 

Big deal.

I run a 1TB raid 5 array in my system right now, and it cost me $600 in drives.
[a href=\"index.php?act=findpost&pid=95416\"][{POST_SNAPBACK}][/a]

If your RAID card fries, so does your data (most likely and unless you want to spend thousands on data recovery service which might or might not recover anything). So you still need backups even if you're running a redundant RAID setup.

But damn, prices really have come down. I'm definitely getting a RAID 5 finally when I get a new computer.
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Ray
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« Reply #42 on: January 13, 2007, 01:49:45 AM »
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You're telling me you've used 10-year-old HDDs? That's, what, 300MB and slow as molasses?

No. I wasn't clear. My practice has been to hand down my old computers to friends, relatives and ex-wife. Those initial hard drives (an 850MB and a 2.1GB) have long since given up the ghost. Another 2 or 3 hard drives around 5, 10 and 20GB have been the victim of a power surge. It's fortunate I wasn't relying upon such drives as a back-up for my images.

I had a selection of my slides transferred to Photo CD by Kodak a year or so before I bought my first computer. I used such discs to test computers in the store whilst shopping around for a suitable computer. This was the days when the average video card was 500kb. 1MB was a premium card and 2MB a rarity. That first computer was the most expensive I've ever bought and slow as molasses, as you say. It took a full 2 minutes for an 18mb image to be read and decompressed.

Those first CD-ROMs from Kodak, now about 14 or 15 years old, are still perfectly readable. My first hard drive (and 2nd, 3rd and 4th etc) are not.

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Anyway, it appears to be a moot argument. It's your time and money you're throwing away.

I don't get you. It takes no more time to burn a CD or DVD than to brush your teeth. The cost is only significant when the technology is new. I wouldn't recommend burning to Blu-ray just yet.

However, in your situation I see the problem. To transfer 1TB of images to DVD would be a mammoth task. Pity you haven't been doing it regularly by degrees. You could then have peace of mind   .

On the cost issue, I should mention that a LaCie 300GB external hard drive, in Australia, costs about A$1 per gigabyte, maybe a bit less now. Blank DVDs are about 10-20 cents per gigabyte.
« Last Edit: January 13, 2007, 02:02:09 AM by Ray » Logged
jani
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« Reply #43 on: January 13, 2007, 06:25:36 AM »
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If your RAID card fries, so does your data (most likely and unless you want to spend thousands on data recovery service which might or might not recover anything).
That depends on how the controller "fries". If it destroys the information stored on the disks, too, then you're out of luck.

If it doesn't, however, you can usually replace it with an identical model controller or a newer controller from the same vendor.

At work, we have successfully upgraded a couple of our RAID 10 setups at least two times this way, and recovered from RAID controller failure once.

We have not experienced complete RAID failure from a fried RAID controller.

This is with the 3Ware 8xxx and 9xxx series controllers.

Unless other RAID controllers are worse, your worries are not very rational.

Worry about Windows corrupting your file system instead.

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So you still need backups even if you're running a redundant RAID setup.

But damn, prices really have come down. I'm definitely getting a RAID 5 finally when I get a new computer.
As I've mentioned in another thread, RAID 5 isn't the "most secure" solution as kaelaria touts.

RAID 5 allows the failure of any single drive, but steals less capacity from the total number of drives; the equivalent of one drive per RAID is "lost" capacity.

RAID 6 beats RAID 5 by using another parity stripe set, and allows for failure of any two drives. The equivalent of two drives per RAID is "lost" capacity.

RAID 1 (mirror) and 10 (AKA RAID 1+0, stripe of mirrors) allows for failure of up to 50% of the drives in the RAID. The capacity of a RAID 1 or RAID 10 set is half of the total drive capacity.

3Ware sells controllers that are pretty efficient at RAID 6, and allow hot spares (unused drives that can be added automatically to the array if another drive fails). A home-building redundancy nut will probably either use mirrored RAID 5 or RAID 6 ("RAID 51" or "RAID 61"), or RAID 10, with such hot spares.

Redundancy nuts with money will purchase storage solutions from e.g. NetApp or EMC, with backup tape robots and a remote storage vault in a mountain.


This redundancy nut isn't quite that paranoid currently, I "mirror" manually to two or three different drives, plus two different DVDs, after each shoot. I expect to go move to dual RAID 10 or something like that in a while.
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jani
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« Reply #44 on: January 13, 2007, 07:06:54 AM »
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As a result, the Chernobyl accident caused a great deal of consternation amongst people living in the vicinity of the accident. Women had abortions, as it now seems, for no good reason at all. As some great American president (or important historical figure) said (who was that?), the only thing we have to fear is fear itself.

Whilst it's true that some people died who were very close to the accident and who received massive doses of radiation (and I hope that I am not seen as trivialising their families' grief), there are lots of people who received moderate amounts of radiation, who've been quaking in their boots for the past 20 years, and who are still as fit as a fiddle.
I am one of those people who have received moderate amounts of radiation because of that accident.

I have, however, not been "quaking in my boots", but others certainly have.

I feel comfortable that the doses of radiation haven't been critically high, and that the chances of me developing cancer aren't significantly higher because of that accident.

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An analysis of the wildlife in the close vicinity of the accident revealed very surprising results. The researchers expected to find all sorts of mutant rats and mice with two heads and three ears, or perhaps no wildlife at all. On the contrary, wildlife was thriving without a hiccup. Moderately strong radiation levels just seemed to have bounced off their back. In fact, it now seems that relatively small amounts of radiation, up to 100 millisieverts (per year) are actually beneficial to us. They stimulate our immune response. An analysis of areas in the United States that have strong, natural background radiation, have shown that people who live in such areas have less cancer, statistically, than people who live in areas with low background radiation.
The "strong, natural background radiation" is peanuts compared to the radiation in areas that were close the Chernobyl accident.

Areas closest to Chernobyl, such as the town of Zaborye in Brjansk, Russia, had concentrations of cesium-137 of above 100 curies per square km.

In an area of approximately 10 300 square km areas around Chernobyl, the concentration of cesium-137 is greater than 15 curies per square km, or more than half a million becquerel per square meter.

An additional 28 600 square km in Russia, Ukraine and Belarus measured 5 curies or more per square km.

Certain areas of Norway received concentrations of about 100 000 becquerel per square meter, enough to make lots of reindeer, sheep and mushrooms unfit for human consumption. (Peruse a map if you don't know how far away that is ...)

The half-life of cesium-137 is about 30 years.

Gomel in Belarus, 130 km northwest of Chernobyl, still has a concentration of 1-5 curies per square km.

A total of eight to ten million people still live under conditions that are more radioactive, but it's suspected that tens of millions risk serious health consequences because of radioactive materials transported by water. How great these risks are is debated, however.

(Feel free to read a bit more)
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feppe
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« Reply #45 on: January 13, 2007, 07:35:39 AM »
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However, in your situation I see the problem. To transfer 1TB of images to DVD would be a mammoth task. Pity you haven't been doing it regularly by degrees. You could then have peace of mind   .

On the cost issue, I should mention that a LaCie 300GB external hard drive, in Australia, costs about A$1 per gigabyte, maybe a bit less now. Blank DVDs are about 10-20 cents per gigabyte.
[a href=\"index.php?act=findpost&pid=95423\"][{POST_SNAPBACK}][/a]

Mr Briot backs up terabytes of data on DVDs as well, but he's doing just that: copying stuff as he goes. This is IMO the only sane way to do DVD backups. But that doesn't solve the issue of verifying their integrity every few years, something I don't consider paranoid at all. I'm in a position to choose my backup regimen as I don't have size-hungry (photographic) backups dating back years, and currently HDDs are the most convenient.

I just checked prices here in Europe. 3.5" hard drives cost ~€0.20 per gigabyte (with €20-50 for the external casing, bringing an external 500GB drive to 25 eurocents per gig) while DVDs cost €0.10 in 100 DVD spindles - their price has gone down drastically here in the past 6 months. So you were right, DVDs are cheaper. But if one puts any money on time spent backing up and verifying it's a no-brainer.

BTW, I doubt hard drives cost three times as much in Australia than in already expensive Europe as your numbers suggest. Perhaps you're looking at the 2.5" prices or prices of some ultra-fast server drives?
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kaelaria
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« Reply #46 on: January 13, 2007, 08:47:45 AM »
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WOW I can't believe the level of absolute PARANOIA around here...lol!!  Either that or some of you should have auditioned for Monk

Some of you can find a theoretical fault with anything, so there IS NO solution for you, pure and simple.

Here in the corporate IT world we use the time tested methods, and are only bound by our departmental budgets.

My web, file and SQL servers are raid 5 arrays with monthly master and daily incrimental tape backups.  OMG the raid card may go out!  OMG the SCSI card could go out!  OMG a meteor could crash through the roof and kill the whole system!!  

At home I backup critical files one and a while from my raid array to an external drive that's only powered on for transfers.  OMG that might break too!!!

You guys sure are entertaining when you try and give computer advice
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jani
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« Reply #47 on: January 13, 2007, 09:05:49 AM »
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I just checked prices here in Europe. 3.5" hard drives cost ~€0.20 per gigabyte (with €20-50 for the external casing, bringing an external 500GB drive to 25 eurocents per gig) while DVDs cost €0.10 in 100 DVD spindles - their price has gone down drastically here in the past 6 months. So you were right, DVDs are cheaper. But if one puts any money on time spent backing up and verifying it's a no-brainer.
Since you're using harddrives, you'll be replacing them every three years or so anyway.

And for integrity's sake, let's assume that you're using RAID 1 or 10 (dual DVDs the competition).

Hard disk densities roughly quadruple every three years for the same price at a certain price point (around €100-200), let's assume that DVDs have a similar price curve, but last at least 20 years if stored properly.

If you shoot 10,000 images of 15 MB each year, and that you now currently have three year's worth of images, that's 450 GB of storage, requiring 2x500 GB drives at roughly €140 each. Then you need a RAID controller, that costs €37 for a four-port controller. (Prices from komplett.nl.)

In three years, you'll need another 2x1000 GB drives at €100 each (because prices don't drop that fast). In three more years, you'll need 2x1500 GB drives at €70 each, if prices for drives keep dropping. In three more years, 2x2000 GB at €50 each.

Hardware cost twelve years, presuming that you change no other components: €720.

DVD writer: €28
200 DVDs €174 + 200 DVDs €120 + 200 DVDs €90 + 200 DVDs €70.

DVD cost, presuming that you change no other components: €442.

But the drives use about 1.5 W in standby mode each. Over twelve years, that adds up to about 120 kWh, if they're turned on 25% of the day. Add 25% power supply overhead, and it's another €20.

So, basically, hard drives are not that much more expensive that it would matter much financially as long as we're sticking to a simple mirrored setup. But if you want your working storage to be online and available, the cost doubles again.

The problem for hard drives is remote location storage of backups, where DVDs win for convenience of transport. If you have access to networked storage, hard drives win on convenience, too.

And arguably, it's easier to verify the data integrity with hard drives.

But given the very small additional cost -- both in time and money -- of creating DVD backups as you go, it is prudent to do both: redundant hard drives and redundant DVDs.
« Last Edit: January 13, 2007, 09:06:10 AM by jani » Logged

Jan
Ray
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« Reply #48 on: January 13, 2007, 09:38:21 AM »
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BTW, I doubt hard drives cost three times as much in Australia than in already expensive Europe as your numbers suggest. Perhaps you're looking at the 2.5" prices or prices of some ultra-fast server drives?
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I'm looking at prices at [a href=\"http://www.computeralliance.com.au/parts.aspx?qrySubCat=HBK]http://www.computeralliance.com.au/parts.aspx?qrySubCat=HBK[/url] which is a local computer store in Brisbane with some of the best prices in town. Internal hard drives vary from around 40 cents to 70 cents per GB, but external hard drives are more expensive, ranging from a bit under a dollar per GB to a bit more than a dollar. A$1 is 0.60 Euros. There are always a few run-out models that are on special and might bring those prices down a bit.

Currently in that store, the best value DVDs are by LG, 16x in spindles of 50 for A$19. That's just 8.4 cents per GB.
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larryg
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« Reply #49 on: January 13, 2007, 09:51:54 AM »
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Strange things happen (what you least expect some times)

Our Novel system crashed.  The Novel program itself.  We have Raid (not sure which one) but the backup software only backed up the data (every night and on Friday with offsite storage)   But since the system itself (Novel) crashed we couldn't get anything going.  

Still working on restoring the Novel System so that we can get the whole system back up.

Redundancy seems to be essential in any arrangement.  Backup Backup and have other supporting systems that will preserve the integrety of the data and the systems.

I Currently:  Have a Raid system  (raid 0) then backup on an external Maxtor
that stays on site another backup on Maxtor goes home (along with archival DVD Gold backups at home).

I can see moving to a 1.5 TB   raid system with other drives as backup to that system.
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Ray
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« Reply #50 on: January 13, 2007, 09:54:13 AM »
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200 DVDs €174 + 200 DVDs €120 + 200 DVDs €90 + 200 DVDs €70.

DVD cost, presuming that you change no other components: €442.

[a href=\"index.php?act=findpost&pid=95457\"][{POST_SNAPBACK}][/a]


Those prices seem a bit inflated, Jani. Right at the moment I could buy 200 DVDs for just 46 Euros at a local store. Are you referring to the gold plated variety?  
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jani
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« Reply #51 on: January 13, 2007, 09:58:09 AM »
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Strange things happen (what you least ex
I Currently:  Have a Raid system  (raid 0) then backup on an external Maxtor
that stays on site another backup on Maxtor goes home (along with archival DVD Gold backups at home).
RAID 0 isn't really RAID.

RAID = Redundant Array of Inexpensive Disks

There is no redundancy in RAID 0.
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jani
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« Reply #52 on: January 13, 2007, 10:01:08 AM »
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Those prices seem a bit inflated, Jani. Right at the moment I could buy 200 DVDs for just 46 Euros at a local store. Are you referring to the gold plated variety? 
No, definitely not gold plated.

Samsung Pleomax 8x
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feppe
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« Reply #53 on: January 13, 2007, 10:06:17 AM »
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WOW I can't believe the level of absolute PARANOIA around here...lol!!  Either that or some of you should have auditioned for Monk

...

You guys sure are entertaining when you try and give computer advice
[a href=\"index.php?act=findpost&pid=95454\"][{POST_SNAPBACK}][/a]

Having two backups, one at home and one at a friend's place or the bank's vault isn't paranoia, it's prudent practice when it comes to your living - if you're a pro - or your memories - if you're an amateur. The added cost and time of making the second backup and taking it off-site once a month or so is negligible compared to the financial and emotional heartache in case of a fire, flood or theft. Sure, there are other things to worry about with such cases, but why gamble on something you _can_ protect?

And no need for ad hominems.
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feppe
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« Reply #54 on: January 13, 2007, 10:09:48 AM »
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I'm looking at prices at http://www.computeralliance.com.au/parts.aspx?qrySubCat=HBK which is a local computer store in Brisbane with some of the best prices in town. Internal hard drives vary from around 40 cents to 70 cents per GB, but external hard drives are more expensive, ranging from a bit under a dollar per GB to a bit more than a dollar. A$1 is 0.60 Euros. There are always a few run-out models that are on special and might bring those prices down a bit.

Currently in that store, the best value DVDs are by LG, 16x in spindles of 50 for A$19. That's just 8.4 cents per GB.
[a href=\"index.php?act=findpost&pid=95459\"][{POST_SNAPBACK}][/a]

You can buy the external HDD as a package and pay premium, or you can buy a "normal" 3.5" HDD and an external casing on the cheap. My prices are based on the latter as I pointed out in my earlier post, and are significantly cheaper than buying an expensive external HDD package.
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Ray
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« Reply #55 on: January 13, 2007, 10:18:02 AM »
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I am one of those people who have received moderate amounts of radiation because of that accident.

I have, however, not been "quaking in my boots", but others certainly have.

I feel comfortable that the doses of radiation haven't been critically high, and that the chances of me developing cancer aren't significantly higher because of that accident.
The "strong, natural background radiation" is peanuts compared to the radiation in areas that were close the Chernobyl accident.

Areas closest to Chernobyl, such as the town of Zaborye in Brjansk, Russia, had concentrations of cesium-137 of above 100 curies per square km.

In an area of approximately 10 300 square km areas around Chernobyl, the concentration of cesium-137 is greater than 15 curies per square km, or more than half a million becquerel per square meter.

An additional 28 600 square km in Russia, Ukraine and Belarus measured 5 curies or more per square km.

Certain areas of Norway received concentrations of about 100 000 becquerel per square meter, enough to make lots of reindeer, sheep and mushrooms unfit for human consumption. (Peruse a map if you don't know how far away that is ...)

The half-life of cesium-137 is about 30 years.

Gomel in Belarus, 130 km northwest of Chernobyl, still has a concentration of 1-5 curies per square km.

A total of eight to ten million people still live under conditions that are more radioactive, but it's suspected that tens of millions risk serious health consequences because of radioactive materials transported by water. How great these risks are is debated, however.

(Feel free to read a bit more)
[a href=\"index.php?act=findpost&pid=95440\"][{POST_SNAPBACK}][/a]

These are exactly the sort of figures that put the wind up people. They sound frightening. In the recent documentary I saw, scientist who had been involved in the research were interviewed. At this point, 20 years after the accident, the only significant increase in cancer has been in Thyroid cancer in children, due to radioactive iodine in milk, it is thought. That's bad enough of course and a real tragedy, but the massive outbreak of cancers such as leukemia doesn't appear to have occurred.

According to the first article you referred to, in Belarus there are 1.8 million people still living in heavily polluted areas and receiving 15 milliSieverts of radiation a year. Is that a typo? It is now thought that doses up to 100 milliSieverts can be beneficial.

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Practically the whole territory was heavily contaminated by radionuclides. More than 1.8 million people are still living in heavy polluted territories. The radiation dose they receive on average amounts to 15 mSv (milliSievert) a year.

Again from Wikipedia:

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Nearly 20 years after the disaster, according to the Chernobyl Forum, no evidence of increases in the solid cancers and, possibly more significantly, none of the widely expected increases in leukemia have been found in the population.
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feppe
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« Reply #56 on: January 13, 2007, 10:19:34 AM »
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The problem for hard drives is remote location storage of backups, where DVDs win for convenience of transport. If you have access to networked storage, hard drives win on convenience, too.

And arguably, it's easier to verify the data integrity with hard drives.

But given the very small additional cost -- both in time and money -- of creating DVD backups as you go, it is prudent to do both: redundant hard drives and redundant DVDs.
[a href=\"index.php?act=findpost&pid=95457\"][{POST_SNAPBACK}][/a]

Excellent, much-needed analysis on potential costs. HD-DVD and/or BluRay might change the picture even further in a year or two, especially if they come up with reasonably-priced multi-layer recordables.

I agree that creating DVD backups as you go is not an issue. But as I've been saying from the beginning, creating the same on HDDs wins purely from the convenience POV - especially when verifying their integrity down the line is taken into account -, even though the price for DVDs is cheaper.

One thing I'd like to point out that HDDs aren't necessarily any harder to transport than DVDs if you design your system for it. You can buy cheap hot-swappable HDD bays for PCs - and easy to retro-fit, also -, which is just as fast to take out as a DVD and just as easy to transport - well, I'd bring static-free pouches with me.
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Ray
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« Reply #57 on: January 13, 2007, 10:26:52 AM »
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You can buy the external HDD as a package and pay premium, or you can buy a "normal" 3.5" HDD and an external casing on the cheap. My prices are based on the latter as I pointed out in my earlier post, and are significantly cheaper than buying an expensive external HDD package.
[a href=\"index.php?act=findpost&pid=95471\"][{POST_SNAPBACK}][/a]

Well, let's not quibble about a few cents here and there. The point is, DVD storage is considerably cheaper than either internal or external hard drive storage.
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Nill Toulme
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« Reply #58 on: January 13, 2007, 11:19:13 AM »
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I backed up to DVD for about six months then lost interest.  There just got to be too many of the darn things.  And as much of a PITA as backing up to DVD is, I don't even want to think about having to restore half a TB or more from DVD.  Yikes!

And I still don't understand the appeal of a mirroring RAID system (e.g., RAID10) over, say, RAID5 plus redundant on- and off-site HDD backups.  Yes it provides more protection against some failure in the RAID itself, but not against all the other stuff that can bite you... OS burps, viruses, surges, operator headspace errors, etc.  Anything that writes a bad file to, or deletes a good file from, one side of the mirror does the same to the other side, does it not?  What good is that?  I'm sure I'm missing something here.

My live data is on a 1.1TB RAID5.  It backs up, automatically and nightly, to external firewire drives.  Those get backed up, manually and weekly or so, to another external drive that otherwise stays at my next door neighbor's.

Hmmm... I probably shouldn't be backing up from my backups, should I.  Maybe I'll change that.

Nill
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jani
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« Reply #59 on: January 13, 2007, 12:08:56 PM »
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According to the first article you referred to, in Belarus there are 1.8 million people still living in heavily polluted areas and receiving 15 milliSieverts of radiation a year. Is that a typo? It is now thought that doses up to 100 milliSieverts can be beneficial.
When you write "it is now thought that ..." you imply that this is the general consensus.

The claim is hardly uncontroversial, it's still only comparatively few researches who believe this may be the case. That isn't necessarily 100 milliSieverts, but "low dosages", which from what I gather means between 1 mSv and a few tens of mSv.

Typical background radiation is around 2.4 mSv per year.

Since you were so fond of quoting only a small part of a pretty long Wikipedia article, only to support your personal view, here's another bit of a Wikipedia article for you:

Radiation poisoning - table of exposure levels and symptoms

As you can see, the levels mentioned as "healthy" in the Taiwan incident were on average 0.4 Sv/21 years, or slightly less than 20 mSv/year on average.

Another article suggests 0.4 cGy/month. 0.4 cGy/month is the equivalent of 4 mSv/month absorbed.

I've been unable to find supporting evidence that continued exposure to approximately 100 mSv/year is beneficial. Smaller doses, maybe, but not undisputedly.

BTW, I guess your source is BBC's Horizon.

Obviously, more research is needed, but it's WAY too early to call such doses generally "safe" or even "healthy", even though it makes for good headlines and punchlines. Keep in mind that journalists tend to present conflicting views of a case, with no regard for which is the most accepted view, in order to seem "neutral".
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