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Old Oct 11, 2012, 02:04 PM   #1
cwright
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Best 3TB Hard Drive for RAID - WD or Hitachi?

Hey all,

I know I have posted before about backup storage for video, but what I'm looking to purchase now is strictly to be used as a work volume, so I figure it deserves its own thread.

I'm looking to buy an 8-drive RAID 5 volume. I've pretty much settled on this enclosure, unless anyone has a better suggestion.

My main concern is over which is the best hard drive that fits within my budget. I think I've narrowed it down to two: Hitachi Deskstar 3TB and Western Digital Red. Unfortunately, the Hitachi Ultrastar drives do not fit within my budget.

Seagate is off the list because it seems their warranties have dwindled to only one year, and both of these offer 3-year warranties. For the last couple years I've been working on three separate internal hard drives - all Hitachi Deskstars (2x 3TB and 1x 2TB). I've been extremely happy with them. No faults or errors, and they're silent and fast.

However I'm also considering the WD Red for it being NAS-optimized. I know the drives are slower at 5400rpm, but given that I've been working off single drives to date, an 8-drive RAID 5 should be far and away faster regardless of whether the drives spin at 7200rpm or 5400rpm. Right? Most of the footage I edit is only 720p, and at the very most I'd be editing a 3-camera 1080p project.

Any suggestions would be greatly appreciated! And as a side note... it's really depressing how much more drives cost these days... the Hitachi's are currently going for $45 more than I paid over a year ago.

EDIT: While the (3) reviews on B&H for the WD Red were good, looks like there are lots of reports on Newegg saying there are severe quality control problems with them now. Maybe I just answered my own question...

Last edited by cwright; Oct 11, 2012 at 02:19 PM.
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Old Oct 11, 2012, 06:30 PM   #2
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Mixed views on Seagate, but...

I recently updated my small NAS with three 3TB Seagate drives leaving one older 2 TB WD in place.

I replaced the other 2 TB drives with the Seagate Constellation ES.2 drives. They come with a 5 year warranty. Just FYI.
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Old Oct 11, 2012, 11:43 PM   #3
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First off, save yourself some cash on the 8-bay enclosure! That one you picked is way too much.
This one does the same thing for a much better price.

I have an identical box built by Sans Digital instead of Rosewill, but it's the same box fitted with mini-SAS instead of eSATA.
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Old Oct 12, 2012, 12:11 AM   #4
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Originally Posted by wonderspark View Post
First off, save yourself some cash on the 8-bay enclosure! That one you picked is way too much.
This one does the same thing for a much better price.

I have an identical box built by Sans Digital instead of Rosewill, but it's the same box fitted with mini-SAS instead of eSATA.
Thanks for the feedback - I've definitely looked at that enclosure and several others that are similar. From what I've found so far, there are significant improvements in reliability and performance with hardware-based RAID solutions over software-based enclosures. I understand that in the enclosure I mentioned, it's driven by the PCI-E card rather than inside the enclosure. I'm not entirely sure if it matters, as it should still be better than an OS-managed RAID (Right?). If anyone more informed on the subject has a different opinion, I'd love to hear it, because the cost difference is pretty substantial.

EDIT: According to your signature, you have an Areca PCI-E RAID controller card? Do you use that with your Sans Digital enclosure? As I understand it, the PCI-E controller card that comes with the DatOptic Enclosure is what makes up the majority of the cost difference. Does that sound about right to you?
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Quote:
Originally Posted by musique View Post
I recently updated my small NAS with three 3TB Seagate drives leaving one older 2 TB WD in place.

I replaced the other 2 TB drives with the Seagate Constellation ES.2 drives. They come with a 5 year warranty. Just FYI.
I'll look into these, but unfortunately those drives seem to be just as pricey as the Hitachi UltraStars.

Last edited by cwright; Oct 12, 2012 at 12:17 AM.
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Old Oct 12, 2012, 12:35 AM   #5
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Originally Posted by cwright View Post
Thanks for the feedback - I've definitely looked at that enclosure and several others that are similar. From what I've found so far, there are significant improvements in reliability and performance with hardware-based RAID solutions over software-based enclosures. I understand that in the enclosure I mentioned, it's driven by the PCI-E card rather than inside the enclosure. I'm not entirely sure if it matters, as it should still be better than an OS-managed RAID (Right?). If anyone more informed on the subject has a different opinion, I'd love to hear it, because the cost difference is pretty substantial.

EDIT: According to your signature, you have an Areca PCI-E RAID controller card? Do you use that with your Sans Digital enclosure? As I understand it, the PCI-E controller card that comes with the DatOptic Enclosure is what makes up the majority of the cost difference. Does that sound about right to you?
----------

I do use the Sans Digital box with my Areca card, and that does sound about right. I get the max speed of my eight HDDs in the box, times 8, which in my AJA System throughput tests, gave 1101MB/second sustained in RAID 0 using all WD RE-4 2TB HDDs, and those same disks in RAID 6 get 816MB/second write, 714MB/second read speeds sustained. This is because I'm not running the data through eSATA, but mini-SAS to the Areca, a much better RAID card.

You could get this Areca card for $570, the same 8-bay box I have (I found it for $399) and have twice the speed for $900 as the $700 one you linked.

Here's the box I have, in black. (Mine is silver.)

I also swapped out the blue LED-lit exhaust fan with a no-light, quieter Noctua fan, and it's much better.
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Old Oct 12, 2012, 12:56 AM   #6
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Originally Posted by wonderspark View Post
I do use the Sans Digital box with my Areca card, and that does sound about right. I get the max speed of my eight HDDs in the box, times 8, which in my AJA System throughput tests, gave 1101MB/second sustained in RAID 0 using all WD RE-4 2TB HDDs, and those same disks in RAID 6 get 816MB/second write, 714MB/second read speeds sustained. This is because I'm not running the data through eSATA, but mini-SAS to the Areca, a much better RAID card.

You could get this Areca card for $570, the same 8-bay box I have (I found it for $399) and have twice the speed for $900 as the $700 one you linked.

Here's the box I have, in black. (Mine is silver.)

I also swapped out the blue LED-lit exhaust fan with a no-light, quieter Noctua fan, and it's much better.
Thanks for the info - very helpful. Not to doubt you regarding the difference in speed at all, but on the DatOptic enclosure I was looking at, the picture seems to show the same dual Mini-SAS via PCI-E system that you're talking about with the system you built. For whatever reason it doesn't actually mention that on the page, but it's pretty clear from the photo. I'm not at all committed to that system, but I'm curious why your Areca card and Sans Digital box would be so much faster, for only a marginal increase in cost, especially if it's the same Mini-Sas connector. I suppose, just a better product and the benefit of building your own system rather than buying a bundled kit maybe?

Also, what are your thoughts on this enclosure? Another Areca product, but with the RAID controller built into the case. Of course it's more expensive, but - money well spent, or no?
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Old Oct 12, 2012, 01:20 AM   #7
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Quote:
Originally Posted by cwright View Post
Thanks for the info - very helpful. Not to doubt you regarding the difference in speed at all, but on the DatOptic enclosure I was looking at, the picture seems to show the same dual Mini-SAS via PCI-E system that you're talking about with the system you built. For whatever reason it doesn't actually mention that on the page, but it's pretty clear from the photo. I'm not at all committed to that system, but I'm curious why your Areca card and Sans Digital box would be so much faster, for only a marginal increase in cost, especially if it's the same Mini-Sas connector. I suppose, just a better product and the benefit of building your own system rather than buying a bundled kit maybe?

Also, what are your thoughts on this enclosure? Another Areca product, but with the RAID controller built into the case. Of course it's more expensive, but - money well spent, or no?
Interesting. I thought that box you linked was eSATA, not mini-SAS, but now I see that it is mini-SAS. Why they rate it slower is a good question that I can't answer. I know different RAID cards give different results, with Atto and Areca being among the top rated. It *could* be that they just under-rate the data speeds possible, or it *could* be that the RAID card they give you is slower. I know when I bought my TR8X box, the specs from Sans Digital showed a max data speed of 750MB/second I believe, which made no sense given that it's just a box with connections that are capable of far more than that, obviously. If I stuck all SSDs in my box, it would no doubt be much faster than 1101MB/second. It's the x8 lane Areca card in an x16 PCI lane that allows max speed on my setup.

The Areca all-in-one package you linked is fine, but I prefer to spend less for the same performance, which is why I went the way I did.

----------

In fact, I think I just answered that mystery. It seems the RAID card they give you is x4 lane, whereas the Areca is x8 lane. That would be half the possible speed right there.
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Old Oct 12, 2012, 01:45 AM   #8
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Interesting. I thought that box you linked was eSATA, not mini-SAS, but now I see that it is mini-SAS. Why they rate it slower is a good question that I can't answer. I know different RAID cards give different results, with Atto and Areca being among the top rated. It *could* be that they just under-rate the data speeds possible, or it *could* be that the RAID card they give you is slower. I know when I bought my TR8X box, the specs from Sans Digital showed a max data speed of 750MB/second I believe, which made no sense given that it's just a box with connections that are capable of far more than that, obviously. If I stuck all SSDs in my box, it would no doubt be much faster than 1101MB/second. It's the x8 lane Areca card in an x16 PCI lane that allows max speed on my setup.

The Areca all-in-one package you linked is fine, but I prefer to spend less for the same performance, which is why I went the way I did.

----------

In fact, I think I just answered that mystery. It seems the RAID card they give you is x4 lane, whereas the Areca is x8 lane. That would be half the possible speed right there.
I haven't looked into the difference between x4 and x8 lane - can you clarify the difference between them (performance-wise), and which product is which?

I think I may have confused myself. I linked you to this Areca product as a comparable option, but price-wise I was l looking at this which is not much more than the combined Areca card and Sans Digital case you recommended - but this one is not mini-SAS. So it looks like your recommendation is a much bigger savings than I thought. I've still got at least 2-3 weeks before my purchase, but I think you've got me headed in the right direction. Thanks!
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Old Oct 12, 2012, 02:13 AM   #9
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I haven't looked into the difference between x4 and x8 lane - can you clarify the difference between them (performance-wise), and which product is which?

I think I may have confused myself. I linked you to this Areca product as a comparable option, but price-wise I was l looking at this which is not much more than the combined Areca card and Sans Digital case you recommended - but this one is not mini-SAS. So it looks like your recommendation is a much bigger savings than I thought. I've still got at least 2-3 weeks before my purchase, but I think you've got me headed in the right direction. Thanks!
I should ask exactly what system you have. You can see I'm on a 4,1 Mac Pro, and you can probably tell that I've upgraded the firmware on it to a 5,1, and put a new CPU in as well. I've been telling you things based on my system, which has two 16-lane and two 4-lane PCI Express 2.0 slots. PCI 2.0 speeds are 500MB/second per lane.

The first 16-lane slot has my 5870 GPU, and the second 16-lane slot has my Areca RAID card. Since the Areca is x8, it runs on 8 lanes x 500MB/sec = 4000MB/second max possible data speed (though I'm sure I'll never see that.) An x4 (4 lane) card can only go half as fast as an x8 lane card can.

This doesn't exactly explain why DatOptic only says the thing will do about 540MB/second maximum, though. They talk about combining two of those systems using sixteen SATA III disks, and still only getting "up to 1000MB/second." I got 101MB/second more using only eight SATA II disks. Someone who knows the DatOptic system will have to explain that one, but from the looks of it, there is a better way.
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Old Oct 12, 2012, 09:31 AM   #10
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I should ask exactly what system you have. You can see I'm on a 4,1 Mac Pro, and you can probably tell that I've upgraded the firmware on it to a 5,1, and put a new CPU in as well. I've been telling you things based on my system, which has two 16-lane and two 4-lane PCI Express 2.0 slots. PCI 2.0 speeds are 500MB/second per lane.

The first 16-lane slot has my 5870 GPU, and the second 16-lane slot has my Areca RAID card. Since the Areca is x8, it runs on 8 lanes x 500MB/sec = 4000MB/second max possible data speed (though I'm sure I'll never see that.) An x4 (4 lane) card can only go half as fast as an x8 lane card can.

This doesn't exactly explain why DatOptic only says the thing will do about 540MB/second maximum, though. They talk about combining two of those systems using sixteen SATA III disks, and still only getting "up to 1000MB/second." I got 101MB/second more using only eight SATA II disks. Someone who knows the DatOptic system will have to explain that one, but from the looks of it, there is a better way.
I actually have the exact same system - an early 2009 Mac Pro upgraded to 5,1 and a 6-core 3.33ghz CPU. Only difference is I have an AMD Radeon HD 6870 graphics card. Sounds like your system is the way to go!
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Old Oct 12, 2012, 01:01 PM   #11
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A bit dated but the following quote is from the Backblaze blog:
"The Hitachi 3TB drive (Hitachi Deskstar 5K3000 HDS5C3030ALA630) is our current favorite for both its low power demand and astounding reliability"

I figured that if a Cloud Backup company likes these drives, they are going to be good for me too. Needless to say I use these in my Synology 2411 :-)

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Old Oct 12, 2012, 02:32 PM   #12
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You could get this Areca card for $570, the same 8-bay box I have (I found it for $399) and have twice the speed for $900 as the $700 one you linked.
So I'm starting to look into separate Mini Sas controller cards now, and this raises more questions. I found this RAID card at B&H. It seems to have the same features at half the price, and would be easier to buy at B&H along with my hard drives. Any reason the Areca card you mentioned would be better?

----------

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A bit dated but the following quote is from the Backblaze blog:
"The Hitachi 3TB drive (Hitachi Deskstar 5K3000 HDS5C3030ALA630) is our current favorite for both its low power demand and astounding reliability"

I figured that if a Cloud Backup company likes these drives, they are going to be good for me too. Needless to say I use these in my Synology 2411 :-)

Patrick
Thanks for the input. Next question. After spending a little extra to go with a Mini Sas RAID solution over eSATA, would it be a bad idea to then put 5400rpm drives in it? I guess the WD Red drives I mentioned early are actually some sort of variable speed and not limited to 5400rpm. Like I said before I'm guessing that when set up in a RAID 5 it will still be plenty fast even with 5400rpm drives, but I'm not really sure...
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Old Oct 12, 2012, 03:05 PM   #13
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So I'm starting to look into separate Mini Sas controller cards now, and this raises more questions. I found this RAID card at B&H. It seems to have the same features at half the price, and would be easier to buy at B&H along with my hard drives. Any reason the Areca card you mentioned would be better?
Not quite all the same features. It doesn't seem to have any on-board memory cache, and also doesn't support other RAID levels, such as RAID 6, which allows TWO drives to fail without data loss, instead of only one. It's saved me once, when I accidentally pulled the wrong drive during a failure.

I know you plan on making a RAID 5, so the second point might not be that valuable to you, but I think the on-board cache helps with speed quite a bit. My card came with 1GB of cache, but is upgradable to 4GB. 1GB is working fine for me so far, and I think it's very important. I also have a BBU (battery backup unit) attached to the RAID card... another great feature of Areca cards.

I think it's worth digging into this before you decide to go with a cheaper card. There are reasons they cost more, and they become critical when something goes wrong.

You have decided to make the move from backup storage use to working data use. That means you REALLY want to have fast, reliable data... unless it's really just for a hobby, and you don't mind losing the whole array for a day or two while you rebuild the array and reload the data from backups. I use mine for my paychecks and survival, so both reliability and speed are very important to me. I have two massive APC UPS units, one for the Mac Pro and RAID box, the other for monitors and other bits. If I pull the plugs, the entire system will continue to run for 45 minutes before I get down to the last battery bars. Further, the BBU on the Areca card ensures that no data loss occurs should I lose power. Might be overkill for you, but these are things to consider.
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Old Oct 12, 2012, 03:51 PM   #14
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Not quite all the same features. It doesn't seem to have any on-board memory cache, and also doesn't support other RAID levels, such as RAID 6, which allows TWO drives to fail without data loss, instead of only one. It's saved me once, when I accidentally pulled the wrong drive during a failure.

I know you plan on making a RAID 5, so the second point might not be that valuable to you, but I think the on-board cache helps with speed quite a bit. My card came with 1GB of cache, but is upgradable to 4GB. 1GB is working fine for me so far, and I think it's very important. I also have a BBU (battery backup unit) attached to the RAID card... another great feature of Areca cards.

I think it's worth digging into this before you decide to go with a cheaper card. There are reasons they cost more, and they become critical when something goes wrong.

You have decided to make the move from backup storage use to working data use. That means you REALLY want to have fast, reliable data... unless it's really just for a hobby, and you don't mind losing the whole array for a day or two while you rebuild the array and reload the data from backups. I use mine for my paychecks and survival, so both reliability and speed are very important to me. I have two massive APC UPS units, one for the Mac Pro and RAID box, the other for monitors and other bits. If I pull the plugs, the entire system will continue to run for 45 minutes before I get down to the last battery bars. Further, the BBU on the Areca card ensures that no data loss occurs should I lose power. Might be overkill for you, but these are things to consider.
This is how I make my living too, so it's definitely critical that there can't be downtime. So I'll go with the Areca card. I've considered a RAID 6 volume and I'm still going back and forth. Given how pricey the drives are right now, I almost hate to reduce the useable space even more with a RAID 6, especially since I'll have separate backups. But I'm not sure. This is already getting to be a bit more expensive than planned by going with the MiniSas RAID card, but maybe I should hold out for a sale on 4TB drives instead and set up a RAID 6 volume with those.

Also, how do you connect a battery backup directly to the RAID card? Any reason to do that in addition to having a backup on the Mac beyond just redundancy?
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Old Oct 12, 2012, 04:38 PM   #15
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This is how I make my living too, so it's definitely critical that there can't be downtime. So I'll go with the Areca card. I've considered a RAID 6 volume and I'm still going back and forth. Given how pricey the drives are right now, I almost hate to reduce the useable space even more with a RAID 6, especially since I'll have separate backups. But I'm not sure. This is already getting to be a bit more expensive than planned by going with the MiniSas RAID card, but maybe I should hold out for a sale on 4TB drives instead and set up a RAID 6 volume with those.

Also, how do you connect a battery backup directly to the RAID card? Any reason to do that in addition to having a backup on the Mac beyond just redundancy?
There's a connector on the RAID card for the battery backup. Rather than use up a PCI slot for the little holder they give you, I put the battery itself in the space beside the GPU when you open up the Mac.

My RAID 6 is 12TB, and you saw how fast it is. I have a feature-length film and dozens of other client projects on the array, and only use about 6TB. I have a lot of spare external and internal disks that I use to back up what I need to, and those Hitachi 4TB 5k4000 disks are great for that as well. Only $250 on Amazon!

The extra BBU is redundancy, and you could get away with skipping it. In case of power failure, it will keep the data in the cache from disappearing, so that when you power the machine back up, it can finish without losing anything. It's not the same purpose as the UPS(s), but if something goes wrong, it's another level of protection. Say the UPS fails, you pull the wrong plug from it, or you've fallen asleep during a render and the power goes out, your UPS dies, and you were unaware... the BBU will last 72 hours or so.
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Old Oct 12, 2012, 04:54 PM   #16
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There's a connector on the RAID card for the battery backup. Rather than use up a PCI slot for the little holder they give you, I put the battery itself in the space beside the GPU when you open up the Mac.

My RAID 6 is 12TB, and you saw how fast it is. I have a feature-length film and dozens of other client projects on the array, and only use about 6TB. I have a lot of spare external and internal disks that I use to back up what I need to, and those Hitachi 4TB 5k4000 disks are great for that as well. Only $250 on Amazon!

The extra BBU is redundancy, and you could get away with skipping it. In case of power failure, it will keep the data in the cache from disappearing, so that when you power the machine back up, it can finish without losing anything. It's not the same purpose as the UPS(s), but if something goes wrong, it's another level of protection. Say the UPS fails, you pull the wrong plug from it, or you've fallen asleep during a render and the power goes out, your UPS dies, and you were unaware... the BBU will last 72 hours or so.
Thanks again for the info. I was hoping to get a RAID array of around 20TB. I already have 9TB of internal hard drives that are so full that I'm overflowing into various 2TB external drives. So around 10TB of the RAID would be filled up instantly, and I'd hope to have enough space leftover to keep working for the next few years above and beyond that.

I'm planning on then taking my existing 2x 3TB internal Hitachi's and setting up a RAID 1 as a backup volume for whatever projects I'm currently working on.

Sounds like 8x4TB for is what I want for a RAID 6 volume of around 22 TB, if I can come up with the extra budget. I wonder if it's worth holding out for any possible sales on 4TB drives on Black Friday?
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Old Jun 2, 2013, 08:18 PM   #17
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Using Raid-5 on such a large array is almost guaranteed to end in losing all your data. Raid-5 is not safe, not even remotely so with todays HDD sizes. Use Raid-6 as a minimum.
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Old Aug 16, 2013, 02:45 PM   #18
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Using Raid-5 on such a large array is almost guaranteed to end in losing all your data. Raid-5 is not safe, not even remotely so with today HDD sizes. Use Raid-6 as a minimum.
Where do you learn that?

Look at the video: http://vimeo.com/29501754

Most mistakes that creates problem with RAID5 are:
- Remove the WRONG drive
- Shut-down the RAID and replace the drive <--- Incorrect
It should be:
- Identified the drive.
- Just hot-swap the failed drive. DO NOT shut down the raid.

I have my eBOX-N 10TB RAID5 over 4yrs 24/7 - replaced ONE HDD
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Old Aug 16, 2013, 03:17 PM   #19
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I love WD.

My sucess with them has been the best, especially compared to Seagate.

Plus, WD was awesome the two times a drive died with in warranty. They sent me a label, I sent them the drive and a week later I had a new one.
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Old Aug 17, 2013, 06:33 AM   #20
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Where do you learn that?

Look at the video: http://vimeo.com/29501754

Most mistakes that creates problem with RAID5 are:
- Remove the WRONG drive
- Shut-down the RAID and replace the drive <--- Incorrect
It should be:
- Identified the drive.
- Just hot-swap the failed drive. DO NOT shut down the raid.

I have my eBOX-N 10TB RAID5 over 4yrs 24/7 - replaced ONE HDD
twitch31 is right, RAID5 on the size of disks these days is quite dangerous. If one 2/3/4TB disk dies and you put a replacement disk into the array, not only does performance take a dive while it rebuilds but the rebuild could take hours or days depending on the controller and disks used. For the whole of that time your array is at the mercy of the elements, another drive failure and your array is gone!

RAID6 will at least give you a bit of breathing room, should a disk failure occur. If the data is mission critical then you should really be looking at RAID10 or 50 at the very least.
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Old Aug 18, 2013, 08:42 PM   #21
twitch31
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Quote:
Originally Posted by FireWire2 View Post
Where do you learn that?

Look at the video: http://vimeo.com/29501754

Most mistakes that creates problem with RAID5 are:
- Remove the WRONG drive
- Shut-down the RAID and replace the drive <--- Incorrect
It should be:
- Identified the drive.
- Just hot-swap the failed drive. DO NOT shut down the raid.

I have my eBOX-N 10TB RAID5 over 4yrs 24/7 - replaced ONE HDD
It's all about unrecoverable read errors (haven't improved for ages in coonsumer drives) and the amount of data that has to be read to rebuild a RAID-5 array. It's at the point now where there's a good change of encountering a URE during a rebuild after a single drive failure in a RAID-5 array. 1 Dead drive + 1 URE during rebuild can mean your array of data is toast (this depends on the RAID-5 implementation).

http://www.zdnet.com/blog/storage/wh...ng-in-2009/162
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Old Aug 19, 2013, 03:43 PM   #22
FireWire2
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Quote:
Originally Posted by twitch31 View Post
It's all about unrecoverable read errors (haven't improved for ages in coonsumer drives) and the amount of data that has to be read to rebuild a RAID-5 array. It's at the point now where there's a good change of encountering a URE during a rebuild after a single drive failure in a RAID-5 array. 1 Dead drive + 1 URE during rebuild can mean your array of data is toast (this depends on the RAID-5 implementation).

http://www.zdnet.com/blog/storage/wh...ng-in-2009/162
URE issue, your HDD is encounter every single day, that's not new.

That is why you have TLER, ECR circuitry in the HDD.
If you have a BAD ERC circuitry like Seagate 7200.11, then whole HDD will freeze, which is you would know right away

Otherwise, you should not worry about that.

All of those 2^14 bit is sensation news.
BTW, do not believe whatever you read! Be skeptical.

Last edited by FireWire2; Aug 19, 2013 at 08:27 PM.
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Old Aug 19, 2013, 03:54 PM   #23
twitch31
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Of course I'm sceptical, but I've heard of enough Raid-5 rebuild failures to be wary of using it.
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Old Aug 20, 2013, 04:49 AM   #24
Ifti
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I use WD Red 3TB drives in my RAID5 array - never had any issues whatsoever. Highly recommended.
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Old Aug 22, 2013, 04:54 PM   #25
FireWire2
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Quote:
Originally Posted by twitch31 View Post
Of course I'm sceptical, but I've heard of enough Raid-5 rebuild failures to be wary of using it.
Heard is not fact :-).

Like today I have a customer who has 16x 3TB as 42TB RAID5+HS
One drive failed it grabs the HS and rebuild the RAID.
But my client saw LEDs flashed, he panics and shuts down the system in the middle of the raid rebuild.
He removes a GOOD drive, base on the IT at HQ office, the whole thing crashed.

He calls me, I was able to remote in and saw the issue ask him to put back the drive
The RAID went back to rebuild.

What i'm saying is RAID5/6 will be as good as the person maintain it.

Last edited by FireWire2; Aug 22, 2013 at 06:41 PM.
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