For something like the drive this thread is about they are using identical drives for SATA and SAS.
You do not get any higher quality, reliability etc going with the SAS versions.
They are not "intended to be the same", they are the same.
WD HDD Ultrastar DC HC520 HUH721212AL4205 12TB 3.5" SAS $76.89
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You do not get any higher quality, reliability etc going with the SAS versions.
They are not "intended to be the same", they are the same.
Why does this just seem like a really cool thing to have on a t-shirt...
I don't think so since many times the power requirements and even sleep features are different between the SAS and SATA models of even the same drive. Perhaps just a different firmware load on the same hardware, but that does seem to affect reliability over time. ymmv.
If you know something about the drives that the manufacturer does not know, please elaborate why you think they are wrong?
For capacity spinners like these the amount of them that is sold as SAS is going down year after year.
- SATA models have lower consumption
- Same reliability now that its the same drives with seperate interface options rather than seperate series like it used to be
- SDS systems like Ceph etc that does not need SAS for multipathing is seeing a massive growth
When im hired on as extra hands for the "fun fun" unpacking and racking of something like a few hundread storage nodes its rare to see SAS drives for capacity.
For large capacity drives they are probably more common as SAS than SATA.
SMR itself is not really the problem, the consumer drives that dont let the host/hba monitor it is a problem.
Host managed SMR is a completely different animal.
Just what people have measured--SAS of the same model as SATA using more power. Sleep requests not honored, etc.
Back in the day, SCSI and non-SCSI were the same physical drive with a different interface board. There were no separate specs for each interface, just an indication (typically by letter) that the interface was one or the other (Maxtor LXT213S and LXY213A immediately come to mind).
Fast forward to the birth of the 'home computer' and the entire industry split into consumer class hardware and enterprise class hardware. Seagate was one of the companies that was really hit hard by this since they were on the enterprise side with their drives while WD was on the consumer side. Every drive manufacturer started to make IDE their consumer drives and SCSI their more professional drives, if they even made any (WD never had SCSI back in the day).
Seagate was hurt by trying to make consumer quality drives cheap since that wasn't their forte. Luckily, they never stopped working on their bread and butter--enterprise drives. In time WD dominated the consumer market where their experience in 'cheap' and 'good enough' paid off. In time WD started to look towards the enterprise segment of the market and pretty much entered it when they bought out HGST.
As interfaces moved from IDE/SCSI to SATA/SAS there was an opportunity to bring the two halves together again as the wholes they once were. And in certain drive models in the enterprise lineups of Seagate and WD we do see this as what appears to be the same drive with two different interfaces. But make no mistake--this isn't the same single drive with two different interfaces of the days of old, it's two different divisions with two different overall goals that happen to intersect on the same drive. And with all the data I've seen on SAS vs SATA, while the enterprise SATA product is a high quality drive, it's still approaching the mountain of reliability from the bottom, while SAS was there all along.
It's not about if one is 'better' than the other because it's all about use case. But if reliability is the only criteria--then SAS--over and over again, SAS.
An excellent point that illustrates the different market approaches that affect the hard products of SAS and SATA.
But host managed SMR is still very rare, no matter what interface it is. Has anyone here even bought these type of drives before?
If they have bought a SAN with spinners in the recent years then the answer is likely yes.
They feel rare in a homelab setting because they are mainly used by closed enterprise SAN type products.
And current SANs is not something you commonly see in lab.
But how large their overall marketshare actualy is would probably suprise most outside of that field.
I belive none of the open/public systems have good host managed support yet (that is not beta/alpha).
We are just now starting to see the first gens of them hitting the used market, so not been much focus on them.
That is also why they are mainly SAS, as they are used in systems that leverage SAS functionality for resilience.
They are the same drive with a variation in controller board by what interface/functionality sku it is.
That they have not always done that does not mean the world does not move forward.
Im not sure what they could possibly have to gain from lieing to their partners and largest clients etc about it?
That would be such a massive liability with no gain to commit fraud at that level.
In the medium old days (15-20 years ago) the market was bifurcated.
enterprise drives for high IOPS were 2.5" and running at 10k or 15k RPM screamers and often used SAS interface.
Consumer drives were SATA, 3.5", and 5400 or 7200rpm.
Calling those higher performance drives "SAS" could be a shorthand, but really the interface was the least important aspect, they were radically different mechanically.
Now there is effectively no market for higher performance spinning HDDs, that's all SSD now. So the enterprise and cloud market has consolidated around 7200 rpm 'nearline' 3.5" HDDs with as much capacity as possible. And that same format gets re-used on the consumer side as well, because there's not much point in having a different manufacturing process for a shrinking consumer market.
enterprise drives for high IOPS were 2.5" and running at 10k or 15k RPM screamers and often used SAS interface.
Consumer drives were SATA, 3.5", and 5400 or 7200rpm.
Calling those higher performance drives "SAS" could be a shorthand, but really the interface was the least important aspect, they were radically different mechanically.
Now there is effectively no market for higher performance spinning HDDs, that's all SSD now. So the enterprise and cloud market has consolidated around 7200 rpm 'nearline' 3.5" HDDs with as much capacity as possible. And that same format gets re-used on the consumer side as well, because there's not much point in having a different manufacturing process for a shrinking consumer market.
If this was truly the case, then why are applications with SAS drives not being populated with cheaper and more available SATA ones of the same model? If they truly were the same, no one would be buying the SAS when hundreds of drives would yield a significant discount.
Makes sense as there aren't as many 2.5" 15k drives new as they once were and they stopped increasing capacity efforts.
But even among 7200 rpm drives, there's a difference between the nearline enterprise SAS ones and the SATA ones. Because rarely will the HP SATA nearlines cost as much as the SAS or typically be in the same nearline category. If HP says they're a different to their customers, I would have to believe them as there is some liability in them lying at that level.
I have a Supermicro CSE 216 server chassis. I recently upgraded the backplane to SAS3 because I stumbled on one for $45 and said "Why the hell not." The chassis is filled with 24 Hitachi 10k 2.5 SAS drives (HUC106045CSS601) that are supposed to be 6G but to my surprise they all negotiated to 12G according to MSM. The MB is a Supermicro X9SCM-F and the HBA is a Inspur 3008IT.
That shift is happening, that is why we see more and more sata in the refurbished market.
As its been happening for long enough that the first gens are getting replaced.
For scale out storage that are the "modern" SDS approach SATA is replacing SAS.
As it does not need SAS for that usecase.
Some of the storage nodes we are seeing hitting the 2nd hand market now does not even support SAS with their standard config.
Its replaced with sata chips to cut consumption on host also.
It's actually pretty quiet. It's used as a backup server so no heavy I/O except during a backup which is 3 or 4 times a year. Most of the time it's in shutdown. It's in the server room so the only time I hear it is on startup when the fans are going full speed but after the slow down I can't hear it at all. My two switches pretty much drown out the noise it makes. As for the HD's themselves, nope, dead quiet, even when reading/writing.
If you've got the hardware then, of course, use it, but today's 3½" 7200RPM drives pass about 1% more length of platter under the head per second and have much higher data densities, so they are much faster in data transfer. And, newer seek mechanisms are as fast or faster at full stroke, so overall, newer 3½" 7200RPM drives beat 2½" 10K in the spinning rust arena. It might be a bit closer for a 15K drive, as that passes 50% more length per second.
Plus, when you find a deal on 800GB (or so) SATA SSDs, you can fill all 24 slots with those, for almost double the storage, and 3x the speed.
Pfft man can someone give me a call when they find that deal? Hah. I mean at a lot of 24x, sounds great!