Avoid WD Red Drives for NAS applications (Any SMR Drives)

Anything from a major manufacturer NAS rated.
I'm sure the IT pro's will be along to recommend something.

Not that I would know--
but the only "problem" is with the speed these smr drives operate,, its a risk thing, if one drive fails the risk is a second will fail while the first is being resilvered(rebuilt)
and if that happens---- its Exit Stage Left for all the data.
so the faster the first is resilvered the safer the system.

This scenario can be somewhat mitigated by buying HDDs from different lots and suppliers

Perhaps Sean will help me and let us know if its CPU speed or disc speed thats the major player here... [tonguewink][biggrin]

all my current storage drives are WD red.
in the past ive used seagate with no issues.
i usually buy on price/gb

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Originally Posted by rar110

One of the WD reds in our NAS has failed. It’s about 5 years old but failed a while ago. Any recommendations on a replacement? Thanks.

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I assume you have an off the shelf unit from one of the NAS manufacturers (if it's one you built yourself I'd be guessing that you'd know what you needed[thumbsupbig]).

If that's the case have a look on their website for a list of manufacturers and drives they support. In principle:

• try to match drives as closely as possible to your existing ones - same model is the perfect solution.
• if the model is no longer available match one with closest characteristics from the same manufacturer
• do not use a drive with a smaller capacity than the smallest you have
• if going larger, generally the NAS will not use additional capacity until all the other smaller drives are replaced with the same or lager capacity ==> wasting your money
• Don't mix CMR and SMR drives keep it all one way or the other ==> your drives are all CMR (good)

In your case I would get a Western Digital Red PRO of the same capacity. These are CMR drives so will be the best match for your existing drives.

Let me know if you have any questions.

EDIT: Actually, you can still get the standard non pro reds with CMR, what size drives do you have?

Quote:

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Originally Posted by Pedro_The_Swift

Perhaps Sean will help me and let us know if its CPU speed or disc speed thats the major player here... [tonguewink][biggrin]

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In this case it's the disk drive itself - SMR drives have to do a lot of additional data writes when handling large data writes:

Shingled magnetic recording - Wikipedia

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Originally Posted by wikipedia

Shingled magnetic recording (SMR) is a magnetic storage data recording technology used in hard disk drives (HDDs) to increase storage density and overall per-drive storage capacity.[1] Conventional hard disk drives record data by writing non-overlapping magnetic tracks parallel to each other (perpendicular recording), while shingled recording writes new tracks that overlap part of the previously written magnetic track, leaving the previous track narrower and allowing for higher track density. Thus, the tracks partially overlap similar to roof shingles. This approach was selected because physical limitations prevent recording magnetic heads from having the same width as reading heads, leaving recording heads wider.[2][3][4]:7–9

The overlapping-tracks architecture complicates the writing process since writing to one track also overwrites an adjacent track. If adjacent tracks contain valid data, they must be rewritten as well. As a result, SMR drives are divided into many append-only (sequential) zones of overlapping tracks that need to be rewritten entirely when full, resembling flash blocks in solid state drives. Device-managed SMR devices hide this complexity by managing it in the firmware, presenting an interface like any other hard disk. Other SMR devices are host-managed and depend on the operating system to know how to handle the drive, and only write sequentially to certain regions of the drive. [4]:11 ff.[5] While SMR drives can use DRAM and Flash memory caches to improve writing performance, continuous writing of large amount of data is slower than with PMR drives.[6][7][8]

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In any system, conventional HDDs (as apposed to SSDs) are always the slowest part of any system - rarely will it be the CPU (speaking of disk I/O operations).

Quote:

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Originally Posted by SBD4

I assume you have an off the shelf unit from one of the NAS manufacturers (if it's one you built yourself I'd be guessing that you'd know what you needed[thumbsupbig]).

If that's the case have a look on their website for a list of manufacturers and drives they support. In principle:

• try to match drives as closely as possible to your existing ones - same model is the perfect solution.
• if the model is no longer available match one with closest characteristics from the same manufacturer
• do not use a drive with a smaller capacity than the smallest you have
• if going larger, generally the NAS will not use additional capacity until all the other smaller drives are replaced with the same or lager capacity ==> wasting your money
• Don't mix CMR and SMR drives keep it all one way or the other ==> your drives are all CMR (good)

In your case I would get a Western Digital Red PRO of the same capacity. These are CMR drives so will be the best match for your existing drives.

Let me know if you have any questions.

EDIT: Actually, you can still get the standard non pro reds with CMR, what size drives do you have?

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Thanks, I have a synology dual nas. I think it’s a DS2??

I have 2TB drives.

Quote:

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Originally Posted by SBD4

rarely will it be the CPU (speaking of disk I/O operations).

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should be using the south bridge, not the north bridge and not touch the cpu at all.*

Quote:

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Originally Posted by rar110

Thanks, I have a synology dual nas. I think it’s a DS2??

I have 2TB drives.

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Search for WD20EFRX you'll get plenty of options to buy. Buy 2 then you'll have a spare if the other old one throws in the towel later.

Quote:

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Originally Posted by Eevo

should be using the south bridge, not the north bridge and not touch the cpu at all.*

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Spot on Eevo![thumbsupbig]

For those who are following along:
Difference Between Northbridge and Southbridge - Pediaa.Com

Quote:

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Originally Posted by SBD4

Spot on Eevo![thumbsupbig]

For those who are following along:
Difference Between Northbridge and Southbridge - Pediaa.Com

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2008 called. They’d like their chipset back.

The old Northbridge/southbridge went away years ago. Regardless, in any generic motherboard based RAID (softraid) the work is done by the CPU anyway (ie either BIOS/EFI drivers until os bring up and then fakeraid in the driver).

Right now avoid the 2-6TB WD EFAX. I just picked up some 8TB purples to try something different although I do have a “few” CMR reds.

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Originally Posted by BradC

2008 called. They’d like their chipset back.

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haha yes true. there is a reason i put an asterix at the end of my sentence. anyway, the principle is the same.