I am looking to get 3X 2TB drives for a RAID5 backup array. I normally buy enterprise-grade 7.2KRPM drives but with current HDD shortage and sky high prices I am looking at cheaper drives. I found a reasonable deal with WD Cavier green however newegg reviews are not great. I can sacrifice speed but not reliability.
Does anyone uses the 2TB cavier green drives? any suggestions?
you really answered your own question with your statement "I can sacrifice speed but not reliability.". considerably lower warranty on the greens.
i currently run black caviars in my Drobo S (2) 2TB and (3) 1TB.
we buy the caviar greens for a work project by the dozen. I acquired a couple and put them in a NAS and they started failing within months whereas the Seagate ES series are going strong after 3 years (1 failure on those though). I probably wont even bother RMA'ing the Caviar.
Next up are some Hitachi 1TB Enterprise level drives
I use simple (no RAID) WD cavier green drives for backup on my home system.
They're fine. Every drive will fail eventually, so you need more than one backup.
But, I wouldn't consider using those drives in a RAID 5 array. WD specs their bit error rate at 1e14 (as compared to 1e15 for their RE "RAID Edition" drives of the same capacity). With RAID 5, you only need one error during a rebuild after a drive fails to make the rebuild fail (and that makes the whole array unusable).
I use four fast (15k RPM) enterprise drives in RAID 1+0 on my server for better speed, reliability, and much faster rebuilds. Disk capacity is so cheap these days that RAID5 doesn't make a lot of sense any more. If performance wasn't important, I think I'd probably even prefer a simple mirror (RAID 1) to RAID 5, just to avoid the hassles of a RAID 5 rebuild. (RAID 5 rebuilds take much, much more time than RAID1+0 or RAID 1, and are more prone to complete failure (due to random bit errors.)
In long term studies, WD does very well, as good as or better than the others.
For every anecdote about failures, there are opposing anecdotes, like mine: I've never had a Western Digital drive fail and it is all I use these days.
As stated above, expect drives to fail. In the long run, buying less expensive drives like WD Green and accepting a failure or two over the long run is cheaper than buying expensive drives that have long warranties. If a drive lasts one year, it is likely to last five years. In five years, drives will be available with a lot more capacity anyway.
aborr wrote:
I use simple (no RAID) WD cavier green drives for backup on my home system.
They're fine. Every drive will fail eventually, so you need more than one backup.
But, I wouldn't consider using those drives in a RAID 5 array. WD specs their bit error rate at 1e14 (as compared to 1e15 for their RE "RAID Edition" drives of the same capacity). With RAID 5, you only need one error during a rebuild after a drive fails to make the rebuild fail (and that makes the whole array unusable).
I use four fast (15k RPM) enterprise drives in RAID 1+0 on my server for better speed, reliability, and much faster rebuilds. Disk capacity is so cheap these days that RAID5 doesn't make a lot of sense any more. If performance wasn't important, I think I'd probably even prefer a simple mirror (RAID 1) to RAID 5, just to avoid the hassles of a RAID 5 rebuild. (RAID 5 rebuilds take much, much more time than RAID1+0 or RAID 1, and are more prone to complete failure (due to random bit errors.)...Show more →
i guess you haven't looked at the hard disk market price lately. that little flood issue in Thailand kinad threw that idea out for awhile.
Monito wrote:
In long term studies, WD does very well, as good as or better than the others.
For every anecdote about failures, there are opposing anecdotes, like mine: I've never had a Western Digital drive fail and it is all I use these days.
As stated above, expect drives to fail. In the long run, buying less expensive drives like WD Green and accepting a failure or two over the long run is cheaper than buying expensive drives that have long warranties. If a drive lasts one year, it is likely to last five years. In five years, drives will be available with a lot more capacity anyway....Show more →
can't agree less. and in 3 years its cost me a total of $13 to replace 2 1TB black caviers under warranty.
the warranty on greens/blues is now 2 years down from 3.
so within the three year period and after 2 the greens/blues fail i'm in the wallet for whatever the newer one costs which is definitally higher then $13 so far
your assumption of if it lasts 1 year it'll likely last 5 is just that an assumption.
sjms wrote:
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i guess you haven't looked at the hard disk market price lately. that little flood issue in Thailand kinad threw that idea out for awhile.
I'm a patient man. I'm hoping that by the fall, after WD's Thai facilites are back in full production, that there will be a good old fashioned price war as WD tries to win back market share from Seagate.
aborr wrote:
I use simple (no RAID) WD cavier green drives for backup on my home system.
They're fine. Every drive will fail eventually, so you need more than one backup.
But, I wouldn't consider using those drives in a RAID 5 array. WD specs their bit error rate at 1e14 (as compared to 1e15 for their RE "RAID Edition" drives of the same capacity). With RAID 5, you only need one error during a rebuild after a drive fails to make the rebuild fail (and that makes the whole array unusable).
I use four fast (15k RPM) enterprise drives in RAID 1+0 on my server for better speed, reliability, and much faster rebuilds. Disk capacity is so cheap these days that RAID5 doesn't make a lot of sense any more. If performance wasn't important, I think I'd probably even prefer a simple mirror (RAID 1) to RAID 5, just to avoid the hassles of a RAID 5 rebuild. (RAID 5 rebuilds take much, much more time than RAID1+0 or RAID 1, and are more prone to complete failure (due to random bit errors.)...Show more →
where do you get those cheap disks, enterprise 2TB drives are going for almost $400 online
Thanks guys for me the issue is losing data I'd dump the drive and not worry about warranty which is 2 years or 3 but I cannot afford losing my photos.
My primary system is actually 2X 10KRPM WD raptors RAID0 and they have been rock solid (knock on wood) since 2007! but I am suspicious about these green drives. unfortunately the WD cavier black is too expensive now.
speedmaster20d wrote:
where do you get those cheap disks, enterprise 2TB drives are going for almost $400 online
My RAID isn't that big. I only use it for 'hot' stuff that I'm currently working with. My backup/archive is on bigger/slower disks. (I don't think you can buy 15k RPM drives anywhere near as big as 2TB each, at least not yet.) But, yes your point is well taken: Fast reliable storage costs a lot more per GB than the slow disks I use for backup. But, per GB, even fast disks cost a small fraction of what they did a few years back.
So the purpose is solely reliable backup, I need at least 4TB capacity and my enclosure takes 4 drives.
given the above I can either get 4X 2TB cheaper drives and do RAID1+0 or 3X more expensive 2TB drives and run RAID5. main issue is reliability.
Based on your experience which one is a better solution?
I dunno. There seem to be lots more 'brands' than there are actual companies that make drives.
To me it appears that there are only three disk drive companies left:
Western Digital (who recently bought Hitachi's disk drive operations).
Seagate (who recently bought Samsung's disk drive business).
Toshiba (who acquired Fujitsu's disk drive division).
This means that Seagate and WD now supply somewhere around 90% of the world's drives, and Toshiba supplies almost all the rest.
All three companies make several lines of drives in different price/performance categories.
It seems to me that they all offer nearly identical products: You choose the specs you need, and then figure out which company is offering the best deal on that size/speed of drive this week.
speedmaster20d wrote:
So the purpose is solely reliable backup, I need at least 4TB capacity and my enclosure takes 4 drives.
given the above I can either get 4X 2TB cheaper drives and do RAID1+0 or 3X more expensive 2TB drives and run RAID5. main issue is reliability.
Based on your experience which one is a better solution?
I'm not a fan of RAID 5 for most uses. It saves some disk space over RAID 1+0, but it's at the expense of slower and less reliable rebuilds when there's a hardware failure.
I'd consider a 4 drive RAID 1+0 array. RAID 1+0 is faster and more reliable than RAID 5, but it doesn't use storage as efficiently as RAID 5. A 4 drive RAID 1+0 array using 2TB drives only lets you store 4TB of data, whereas a 4 drive RAID 5 array using 2TB drives lets you store 6 TB of data.
The important thing for me is to have three copies of all my files:
1. a current 'working' version of the files
2. a recent snapshot (backup) of the working version in an external enclosure of some sort
3. another backup, stored off-site in some safe place, far from the computer
If you need to look at a file, you use the working version.
If the working version gets messed up due to an accident, or virus, or hardware failure, you restore it from the backup.
If you lose the on-site backup due to fire, flood, theft, etc., you still have the off-site backup to use to rebuild your system
aborr wrote:
The important thing for me is to have three copies of all my files:
1. a current 'working' version of the files
2. a recent snapshot (backup) of the working version in an external enclosure of some sort
3. another backup, stored off-site in some safe place, far from the computer
If you need to look at a file, you use the working version.
If the working version gets messed up due to an accident, or virus, or hardware failure, you restore it from the backup.
If you lose the on-site backup due to fire, flood, theft, etc., you still have the off-site backup to use to rebuild your system...Show more →
+1000. no raid needed, perhaps only for speed matters
aborr wrote:
I'm not a fan of RAID 5 for most uses. It saves some disk space over RAID 1+0, but it's at the expense of slower and less reliable rebuilds when there's a hardware failure.
I'd consider a 4 drive RAID 1+0 array. RAID 1+0 is faster and more reliable than RAID 5, but it doesn't use storage as efficiently as RAID 5. A 4 drive RAID 1+0 array using 2TB drives only lets you store 4TB of data, whereas a 4 drive RAID 5 array using 2TB drives lets you store 6 TB of data.
The important thing for me is to have three copies of all my files:
1. a current 'working' version of the files
2. a recent snapshot (backup) of the working version in an external enclosure of some sort
3. another backup, stored off-site in some safe place, far from the computer
If you need to look at a file, you use the working version.
If the working version gets messed up due to an accident, or virus, or hardware failure, you restore it from the backup.
If you lose the on-site backup due to fire, flood, theft, etc., you still have the off-site backup to use to rebuild your system...Show more →
How long does it take to rebuild a 3 Disk RAID5 array? I am using a dedicated adaptech RAID controller.
sjms wrote:
can't agree less. and in 3 years its cost me a total of $13 to replace 2 1TB black caviers under warranty. the warranty on greens/blues is now 2 years down from 3. so within the three year period and after 2 the greens/blues fail i'm in the wallet for whatever the newer one costs which is definitally higher then $13 so far your assumption of if it lasts 1 year it'll likely last 5 is just that an assumption.
Nope. Lookup the "bathtub curve".
Again, a writer is confusing anecdotes for evidence.
aborr wrote:
The important thing for me is to have three copies of all my files:
1. a current 'working' version of the files
2. a recent snapshot (backup) of the working version in an external enclosure of some sort
3. another backup, stored off-site in some safe place, far from the computer
If you need to look at a file, you use the working version.
If the working version gets messed up due to an accident, or virus, or hardware failure, you restore it from the backup.
If you lose the on-site backup due to fire, flood, theft, etc., you still have the off-site backup to use to rebuild your system...Show more →
It's the only way to go (with a few variations on that theme).
Three copies of every file, with one off-site. Easy to remember, easy to implement, and inexpensive. A RAID set (of any kind) is a single unit and thus effectively a single copy of the file. Use RAID for performance primarily, high availability secondarily (for high pressure 24/7 commercial enterprise), and not for backup in-and-of-itself.
