I learned this lesson a few years ago with Seagate SMR drives and a 3ware 9650se. It’s nice to see the Will cameo in a video too. They are also not doing a realistic test since it seems they are not putting a workload on the NAS during rebuilds? Most people do not understand how complex SMR is when data needs to be moved from a bottom shingled track. They’re using the technical block size and command bits to hide that they’ve done a less thorough experiment. They are using smaller capacity drives with different NAS systems. I have a problem with your RAIDZ test: normally I replace failed disks with brand new, just unpacked ones, not the ones that were used to write a lot of data and immediately disconnected. Clearly the problem is with the label on the drive. It’s also a great job having the balls to publish something like this to help your readers instead of serving WD’s interests. (2) WDC WD40EFRX-68N32N0 : 4000,7 GB [2/0/0, sa1] – wd https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/product/internal-drives/wd-red-hdd/data-sheet-western-digital-wd-red-hdd-2879-800002.pdf. Background: Fortunately I bought WD Red 4TB drives a long time ago and they are EFRX and they were used in a RAID system. Great piece STH. +1 on rep for it. I think you should explain how SMR works with a bunch of images or an animation. 🙂 Great to see some hard facts related to this after reading about it from others. Gladly, i checked my WD ELEMENTS drives, a NONE of the internal drives is PLAGUED by SMR! page https://www.westerndigital.com/products/internal-drives/wd-red-hdd. The drives are Seagate Barracuda ST500LM050 drives from the same or similar batch. An article like this has a high likelihood of ruffling feathers, so we wanted to have as many bases covered as possible. Shucking external drives (which are often SMR) is mentioned on both pages. I’d really like to go through all my drives and explicitly verify which ones are SMR vs CMR. We have maybe 200 CMR Reds that we’ve bought over the last year. But for a consumer case is the whole SMR debate a real problem? We are going to start with some general benchmarks to try and place the WD Red (WD40EFAX) performance in a larger context. Would be interesting to test on consumer devices such as Synology or QNAP ? I needed 3 x 10TB drives, I went with barely used open-box HSGT He10 on eBay (all 2019 models with around 1,000 hours usage). Robert, that video is very hard to follow. You’d be surprised how often we see clients do this panic and put in new drives. STH articles have always had the feel of ‘real news’ to me–from the easystore article to this one, highlighting the true pros and cons. https://arstechnica.com/gadgets/2020/05/western-digital-gets-sued-for-sneaking-smr-disks-into-its-nas-channel/, Form to join the class: Now I know I’ve sold my customers FreeNAS hardware that isn’t good. (2) WDC WD40EFRX-68N32N0 : 4000,7 GB [2/0/0, sa1] – wd It is strange not to at least generate some workload during a rebuild. Their insight into the drive being used while doing the rebuild is great too. I heard beeping and took me a while to figure out what was beeping. WTF is that??? For the test configuration, we wanted a configuration that de-emphasized CPU performance. They’re using the technical block size and command bits to hide that they’ve done a less thorough experiment. Their insight into the drive being used while doing the rebuild is great too. Great article, thanks for the info. Write tests tell a mostly similar story. Reds aren’t cheap either, but they’ve previously been good. Fortunately I bought WD Red 4TB drives a long time ago and they are EFRX and they were used in a RAID system. Robert Dole, In my opinion, the SMR Reds are a case of fraudulent advertising. Any chance anyone has a link to that? You have entered an incorrect email address! The differences between SMR and CMR are fairly nuanced where regular STH readers may understand, but those regular readers are the same IT professionals that keep up on the latest technology trends in the market. Save my name, email, and website in this browser for the next time I comment. Without LVM file systems, just plain MD-RAID single file system. Robert – I generally look for low-cost CMR drives, and expect that they will fail on me. Good analysis. Next, we are going to get to our test results before getting to our final words. In the Video Patrick says 9 days. On top of which you badly tried to cover it up before finally facing it up. And after that, plague all the other lines (like the BLUE one, that already has 2 drives with SMR). Finally a reputable site has covered this. In both cases, the WD Red SMR drives would not work for me personally. These targeted tests are not designed to be comprehensive, but instead, illuminate any obvious differences between the SMR drive and its CMR competitors. My use case would just be me and my wife, and once the newborn is at age, perhaps him? Even with a new motherboard the problem persisted. This has been the standard technology behind hard drive data storage since the mid-2000s. At least WD is now showing which model numbers are CMR or SMR on their spec. Is WD USING RAID / more demanding users as “guinea pigs” to test SMR and then move on and use SMR on +14TB drives (that currently use HELIUM inside to bypass the theoretical limitation of 6 platters / 12 heads)??? P.S. You don’t test a drive before putting it into a rebuild scenario? I have many WD external drives, and i DON’T WANT any drive with SMR!!! On top of which you badly tried to cover it up before finally facing it up. Effectively we wanted to take CPU performance out of the equation to focus on drive performance. It seems like a marketing TEST!!! At the end of the youtube, it clearly shows a WD produced spec sheet that shows which drives are SMR vs CMR. here they compared a Rebuild with mixed drives and the results were not as sever ? AFAIK, the SMR Reds support the TRIM command. Absent that context, simply putting the word “SMR” in a product listing does not help an uninformed purchaser choose the correct product. They go way too in-depth on the technical side, but when you’re looking at it, they did a less good experiment. As a perpetual dabbler, he is always open to new solutions for old problems. Maybe I’m in the minority here. I’m fine with the drive makers selling SMR drives. I needed 3 x 10TB drives, I went with barely used open-box HSGT He10 on eBay (all 2019 models with around 1,000 hours usage). Stupid WD support… ). According to iXsystems, WD Red SMR drives running firmware revision 82.00A82 can cause the drive to enter a failed state during heavy loads using ZFS. Next, we will move on to the tests focused on the WD40EFAX and NAS RAID arrays. We can hypothesize that there is a negative impact, but it is better to show it. To keep the comparison, use the same disk configuration of 4 x 4TB CMR disk in a RAID-5. https://arstechnica.com/gadgets/2020/05/western-digital-gets-sued-for-sneaking-smr-disks-into-its-nas-channel/, Form to join the class: 2) For backup purposes SMR HDD and QLC SSD is a good choice. Gladly, i checked my WD ELEMENTS drives, a NONE of the internal drives is PLAGUED by SMR! Thank you to Will for doing this testing and Patrick for making it happen. (EDIT -> COPY or CTRL-C). These NFL players use their star power to make a difference Weekend Movie Releases – February 5th - February 7th Migos and … And really nobody (you, too) mentions how inefficient this is in case of power consumption as all the reading and writing while moving the data on a top shingle consumes energy while an CMR drive is sleeping all the time. Ars articles always lack the depth of real reporting, but do provide an entertainment factor and many times the commenters have much more insight (which is what I love finding and reading). I will NEVER buy another EXTERNAL WD drive again without the warranty to check the internal drive MODEL first!!!! They have a WD Red in stock so you buy it and install it without doing a day’s worth of online research. Purpose built for multi-user NAS environments, IronWolf is perfect for teams needing to store more and work faster. But you are not showing how long does it take for an array to rebuild under those conditions? As an individual drive, the WD40EFAX is performing pretty well in these benchmarks. Good analysis. Specifically, RAID arrays our readers use. In some ways, this is like timing a runner’s sprint time after running a marathon. I use ZFS on it, with snapshots, so it actually stores multiple backups. WTF is that??? We do want to point out that we likely want to see a more rigorous drive certification process at iXsystems, but also that they at least have done a good job communicating it on their blog. I will also say that a likely part of the problem here is that these are DM-SMR drives that hide the fact they are SMR from the host. This is a significant workload, but we wanted to stress the drives to ensure we could get separation. When that happens the drive has no choice but to write directly to SMR and invoke a performance penalty. In either case, we suggest not using them. Compare this with the “INFECTED” SMR drive list, and you’re good to go! It takes balls to do it but know I appreciate it. That said, his personal IT motto has to be "if it's not broke, don't fix it" so sometimes the old ways are best. I just want a clear demarcation. During this time, scrubs were disabled for the pool and resilvering priority was completely disabled. We have maybe 200 CMR Reds that we’ve bought over the last year. https://www.hattislaw.com/cases/investigations/western-digital-lawsuit-for-shipping-slower-smr-hard-drives-including-wd-red-nas/, I just ordered 3 WD 4TB Red for a new NAS and had no clue! (1) WDC WD20EARX-00PASB0 : 2000,3 GB [1/0/0, sa1] – wd First up, the new SMR drive has been put through a handful of standard benchmarks just to see how it performs in the context of a larger pool of drives. To be crystal clear, I knew what SMR was, and that the drive used it. Just read this bollocks: https://arstechnica.com/gadgets/2020/06/western-digitals-smr-disks-arent-great-but-theyre-not-garbage/2/. Such a shame, I was happy with putting red drives into client Nas now I will be putting ironwolf, what were Western digital thinking? I’d really like to go through all my drives and explicitly verify which ones are SMR vs CMR. Any chance anyone has a link to that? That’s terrible practice. Still, the WD Red line reaches well beyond the iXsystems blog audience and even to local retail channels where these drives may be purchased without the benefit of online research. Even with a cache flush they’re hitting steady state because of the rebuild. You don’t need to do it with CMR drives either. I know I’m being a d!ck here but the video has a much more thorough impact assessment while this is more showing the testing behind what’s being said in the video. In my opinion, the SMR Reds are a case of fraudulent advertising. Is WD USING RAID / more demanding users as “guinea pigs” to test SMR and then move on and use SMR on +14TB drives (that currently use HELIUM inside to bypass the theoretical limitation of 6 platters / 12 heads)??? This is once again largely due to the manufacturing technique of HDD becoming far more efficient, as well as SSD media becoming lower in price. It is indeed a good sign to see STH calling BS when it is… BS. Just got off the phone with a Seagate rep. And I’m fuming right now. I’d like to say thanks to Seagate for keeping CMR IronWolf. But, selling SMR as a NAS drive, AND not clearly labeling it, (like Red Lite), that should be criminal. Also, if you trim the entire disk (and maybe wait a little), does it return to initial performance? Background: With this piece, we have a companion video: While our YouTube presence is still small compared to the STH main site, we thought this was an important enough finding that we should try reading those who may be impacted. I don’t want a mechanical disk that overlaps tracks and has to write adjacent tracks just to write a specific track!!! For my use, (it was the only 8TB drive on the market for a reasonable price at that time), it works well. For single drive installations, the WD40EFAX will likely function without issue. I second the motion to re-test with Linux MD-RAID. I’m guessing the CMR model is an older one as I bought mine a few years ago now. They were apologetic, but then they dropped the bombshell: All Seagate 2.5″ drives are SMR, they no longer make 2.5″ PMR drives. Friends don’t let friends use SMR drives for NAS. Impossible to replace a disk in a RAID5 array, the controller would eventually fail the rebuild. Taking into account that you regularly make backups from the backups. https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/product/internal-drives/wd-red-hdd/data-sheet-western-digital-wd-red-hdd-2879-800002.pdf. https://www.youtube.com/watch?v=sjzoSwR6AYA. How BIG is it? Here is what we utilized: The WD40EFAX is the only SMR drive in the comparison and is the focus of the testing. The WD Green Series of Hard Drives for Lower Power Consumption for quieter and Cooler requirements The WD Green series, once very popular, is largely overlooked these days. NAS drives are always a gamble, SMR or not, you should always keep away from the cheap HDD drives and that also includes cheap SSD’s if you are trying to have a NAS that have a good performance in a Raid setup. Testing commenced immediately after the drive prep was completed. It can be… BUT, before that happens, WD is probably using the most demanding customers / environments to TEST SMR tech so they can DEPLOY them in the bigger capacity DRIVES: 8, 10, 12, 14TB and beyond (do not currently exist). In the Video Patrick says 9 days. If you are reading this piece, and know someone who uses, or may use WD Red drives in NAS arrays but may not keep track of trends, send them this article, a chart from it, or the video. This site uses Akismet to reduce spam. Note that currently, the MAX capacity drive using SMR is the 6TB WD60EFAX, with 3 platters / 6 heads… So… is that it?? Customers MUST be informed of this new tech, even those using EXTERNAL SINGLE DRIVES ENCLOSURES!!! At least WD is now showing which model numbers are CMR or SMR on their spec. More trolls on STH when you get to these mass audience articles. By opting-in you agree to have us send you our newsletter. At the start you’d think he’s anti-WD but by the end you realize he’s actually anti-Red SMR. Will has worked in both big enterprise and small business IT since 2001. These tests were performed as rapidly as possible to minimize drive idle time between them. I filed a support request with Seagate. Using older WD Reds in a server with ZFS raid, and thinking about buying more on sale… big eye opener here. Western Digital 4TB WD Red Pro NAS Internal Hard Drive - 7200 RPM Class, SATA 6 Gb/s, CMR, 256 MB Cache, 3.5" - WD4003FFBX ... and lower power consumption. They were priced like new WD Red 10TB 😉. Friends don’t let friends use SMR drives for NAS. And this is VERY BAD NEWS. So they go way into the weeds of commands (that the average QNAP, Synology, Dobo user has no clue about) then say it’s fine… oh but for ZFS its still sucks. Well, i got new for you: crystaldiskinfo CAN!!! The platters are paired with magnetic heads, usually arranged on a moving actuator arm, which … In both cases, the WD Red SMR drives would not work for me personally. The RAIDZ resilver test is of particular interest, since the WD Red drive is marketed as a NAS type drive suitable for arrays of up to 8 disks. 2) For backup purposes SMR HDD and QLC SSD is a good choice. I generally tell people RAID arrays tend to operate at the speed of their slowest part. page https://www.westerndigital.com/products/internal-drives/wd-red-hdd. A resilver or RAID rebuild involves an enormous amount of data being read and written, and has the potential to be heavily impacted by the performance penalties of SMR technology. Spend a little bit more money for the 54/5600 – 7200 RPM drives that are CRM. I passed this article around our office. AFAIK, the SMR Reds support the TRIM command. IronWolf Pro, on the other hand is for businesses and digital artists who need extremely high performance from their NAS servers. Well, i got new for you: crystaldiskinfo CAN!!! They were priced like new WD Red 10TB 😉. Top Hardware Components for FreeNAS NAS Servers, Top Hardware Components for pfSense Appliances, Top Hardware Components for napp-it and Solarish NAS Servers, Top Picks for Windows Server 2016 Essentials Hardware, The DIY WordPress Hosting Server Hardware Guide, RAID Reliability Calculator | Simple MTTDL Model, Shingled Magnetic Recording Technologies for Large-Capacity Hard Disk Drives, STH Q2 2020 Update A Letter from the Editor, Microchip NVMe-SAS-4-SATA SmartROC 3200 and SmartIOC 2200 Launched, Marvell NativeRAID NVMe RAID for M.2 Solutions Comes to HPE, https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/product/internal-drives/wd-red-hdd/product-brief-western-digital-wd-red-hdd.pdf, https://www.westerndigital.com/products/internal-drives/wd-red-hdd, https://arstechnica.com/gadgets/2020/05/western-digital-gets-sued-for-sneaking-smr-disks-into-its-nas-channel/, https://www.hattislaw.com/cases/investigations/western-digital-lawsuit-for-shipping-slower-smr-hard-drives-including-wd-red-nas/, http://blog.robiii.nl/2020/04/wd-red-nas-drives-use-smr-and-im-not.html, https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/product/internal-drives/wd-red-hdd/data-sheet-western-digital-wd-red-hdd-2879-800002.pdf, https://crystalmark.info/en/software/crystaldiskinfo, https://arstechnica.com/gadgets/2020/06/western-digitals-smr-disks-arent-great-but-theyre-not-garbage/2/. Period! Since then, I standardized on 10 TB which are CRM. I didn’t specifically checked for it back then because, you know, N300 series. I thought it was good in explanation, but it’s odd. That’s why STH is a gem. Ektich we load test every drive before we replace them in customer systems to ensure we aren’t using a faulty drive. Just read this bollocks: https://arstechnica.com/gadgets/2020/06/western-digitals-smr-disks-arent-great-but-theyre-not-garbage/2/. It is called shingled because the data tracks can be visualized like roofing shingles; they partially overlap each other. In PCMark8, the WD40EFAX manages to outperform the CMR WD40EFRX. Get the best of STH delivered weekly to your inbox. would be interesting to see RAID rebuild time on a more conventional RAID setup. SMR drive support is getting better when hosts know they are using SMR drives. Obviously this CMR cache will have a limited capacity, and with enough write operations can be exhausted. We are also testing a common use case that many may not think of. As a perpetual dabbler, he is always open to new solutions for old problems. With all the recent controversy regarding WD, Toshiba, and Seagate slipping SMR drives into retail channels and failing to disclose the use of their slower technology, we thought it would be interesting to dive into the actual impact of using a SMR drive. If we’d said 10 days, someone could come along and say we were exaggerating the issue. hey thanks for the quick reply! To that end, today we will be comparing a WD Red 4TB SMR drive to its CMR predecessor, as well as CMR drives from other manufacturers. Finally, a FreeNAS RAIDZ resilver was performed. yes indeed they only compare rebuilding while there is no other access. The WD Red is a device-managed SMR drive, which presents itself to the operating system as a normal hard drive. There was no information on whether the drives are SMR or PMR, and there were NO indication whatsoever that they should not be used in RAID arrays. I don’t want a mechanical disk that overlaps tracks and has to write adjacent tracks just to write a specific track!!! I passed this article around our office. Thanks for putting your readers first with stuff like this. We use ZFS heavily and many of our readers do as well. At the end of the youtube, it clearly shows a WD produced spec sheet that shows which drives are SMR vs CMR. Instead, it is a WD Red drive with NAS branding all over it. I know I’m being a d!ck here but the video has a much more thorough impact assessment while this is more showing the testing behind what’s being said in the video. We wanted to present a real-world use case with ZFS so our readers have some sense of the impact. Paste it to a text editor, and voila!!! Learn how your comment data is processed. Very interesting, very disconcerting. The ability to keep systems running and maintaining operations is a key feature of NAS/ RAID systems. Silicon Power Superior Pro 256GB microSDXC Memory Card Western Digital WD_BLACK SN850 1TB NVMe PCIe 4.0 Solid State Drive Silicon Power US70 1TB M.2 PCIe 4.0 Solid State Drive ADATA XPG GAMMIX S50 Lite 1TB PCIe 4.0 M.2 Solid State Drive SecureUSB BT Encrypted Flash Drive Silicon Power UD70 2TB M.2 … Top Hardware Components for FreeNAS NAS Servers, Top Hardware Components for pfSense Appliances, Top Hardware Components for napp-it and Solarish NAS Servers, Top Picks for Windows Server 2016 Essentials Hardware, The DIY WordPress Hosting Server Hardware Guide, RAID Reliability Calculator | Simple MTTDL Model, STH Q2 2020 Update A Letter from the Editor, Microchip NVMe-SAS-4-SATA SmartROC 3200 and SmartIOC 2200 Launched, Marvell NativeRAID NVMe RAID for M.2 Solutions Comes to HPE, https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/product/internal-drives/wd-red-hdd/product-brief-western-digital-wd-red-hdd.pdf, https://www.westerndigital.com/products/internal-drives/wd-red-hdd, https://arstechnica.com/gadgets/2020/05/western-digital-gets-sued-for-sneaking-smr-disks-into-its-nas-channel/, https://www.hattislaw.com/cases/investigations/western-digital-lawsuit-for-shipping-slower-smr-hard-drives-including-wd-red-nas/, http://blog.robiii.nl/2020/04/wd-red-nas-drives-use-smr-and-im-not.html, https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/product/internal-drives/wd-red-hdd/data-sheet-western-digital-wd-red-hdd-2879-800002.pdf, https://crystalmark.info/en/software/crystaldiskinfo, https://arstechnica.com/gadgets/2020/06/western-digitals-smr-disks-arent-great-but-theyre-not-garbage/2/. So they go way into the weeds of commands (that the average QNAP, Synology, Dobo user has no clue about) then say it’s fine… oh but for ZFS its still sucks. Was there nobody on the team who realised the consequences? Luke, Sometimes they put in blues or whatever because that’s all they can get. Plus, I’d like to see some stock hardware RAID devices tested along the same lines. A drive is then removed from the array, and our test drives will be inserted in its place and the resilver timed. I am running a 6×2.5″ 500GB RAID10 array for a total of 3TB for my Steam library. Using older WD Reds in a server with ZFS raid, and thinking about buying more on sale… big eye opener here. Luke, I already changed motherboard once because I thought it was a motherboard issue. I’m also happy to see you tried on a second drive. However, the WD40EFAX is not a consumer desktop-focused drive. We’ve found it fitting to resurrect this WD Blue, Black, Green, Red, and Purple drive naming scheme explanation. As a mitigation against this penalty, writes can be cached to a segment of the drive that operates with CMR technology, and during idle time the drive will spool those writes out to the SMR area. Is that the next step? Great article as always. They are also not doing a realistic test since it seems they are not putting a workload on the NAS during rebuilds? So glad I got 12TB Toshibaa N300’s last year that are CMR. Checked the invoice and they are marked as WD40EFRX (phew)…. My use case would just be me and my wife, and once the newborn is at age, perhaps him? While it’s running well enough at the moment, does anyone know if a scrub is likely to cause a problems with SMR drives? CMR was tested in the same way so I don’t see how its a bad test. Yes, there is an array running here, due to the brilliance of picking drives from different production runs and vendors, that has half SMR and half CMR. Does it strongly depend on the Type of RAID and Filesystem ? On the WD Red drives, the 64MB cache CMR drives are still available and worked great in our testing. The WD Green Series of Hard Drives for Lower Power Consumption for quieter and Cooler requirements The WD Green series, once very popular, is largely overlooked these days. I received a phone call from the rep this morning. Such a shame, I was happy with putting red drives into client Nas now I will be putting ironwolf, what were Western digital thinking? And really nobody (you, too) mentions how inefficient this is in case of power consumption as all the reading and writing while moving the data on a top shingle consumes energy while an CMR drive is sleeping all the time. Perhaps that was because we were testing the use of the drive as a replacement rather than building an entire array of SMR drives. WD has not provided the specifics of how their drives mitigate against the performance impact of using SMR, so we are operating on guesswork as to the size or even existence of a CMR cache area in the WD Red. The WD40EFAX is demonstrably a worse drive than the CMR based WD40EFRX, and assuming that you have a choice in your purchase the CMR drive is the superior product. And after that, plague all the other lines (like the BLUE one, that already has 2 drives with SMR). Do I need an expensive CMR (Ironwolf Helium), a “cheaper” SMR Red NAS drive or will a standard barracuda 8TB SMR “Archive Drive suffice”, for Media (Plex) and Photos. IronWolf vs. IronWolf Pro – Features The biggest difference between the two is this: IronWolf is aimed at Home, SOHO and small business NAS drives with up to 8 drive bays. Granted, this is a good article that demonstrates what happens when SMR cache is filled and disks don’t have enough idle time to recover, but I doubt this happens a lot in the real life, and your advice to avoid SMR does not follow from the data you’re obtained. How BIG is it? Your video and web are usually much closer to 1 another. So take your time and pick your storage depending on your needs. Even after it came out we thought the experiment worthwhile since the number of users that read the iXsystems blog is likely a minority, even among STH readers. If you watch the video, it’s funny. To be crystal clear, I knew what SMR was, and that the drive used it. I will also say that a likely part of the problem here is that these are DM-SMR drives that hide the fact they are SMR from the host. hey thanks for the quick reply! I’m really frustrated. Clearly the problem is with the label on the drive. I’m guessing the CMR model is an older one as I bought mine a few years ago now. Duplicity or lazy indifference or both? The other three drives in the array remain consistent. Things get worse when Steam needs to preallocate storage space for new games, often I have to leave the machine alone for two to three hours. Yes, there is an array running here, due to the brilliance of picking drives from different production runs and vendors, that has half SMR and half CMR. We had two main areas of testing. I just want a clear demarcation. WD technicians don’t have a way to query the drive and ask for the model number?? Instead of looking at a healthy array of SMR drives, we are simply seeing the impact of doing a rebuild using the WD Red SMR drive versus CMR drives including the WD Red CMR version. After that, some more targeted tests were run, pitting the WD40EFAX against three other CMR 4TB drives in a standard ZFS RAIDZ operation: rebuilding an array with a new drive after a drive has failed. They are using smaller capacity drives with different NAS systems. We wanted to present a real-world use case with ZFS so our readers have some sense of the impact. But, selling SMR as a NAS drive, AND not clearly labeling it, (like Red Lite), that should be criminal. Designed for up to 8 bays and featuring ultra-high capacity of 10TB and speeds of up to 210MB/s, these internal hard drives are specifically built for less wear and tear, little to no noise/vibration, no lags or down time, increased file-sharing performance, and lower power … But you are not showing how long does it take for an array to rebuild under those conditions? I wonder to what extent can performance be regained with its use. When data is written on a SMR drive the data on the overlapping tracks will be affected by the write process as well. They work aggressively in the background to mitigate their own limitations. I received a phone call from the rep this morning. My backup window is not time constrained, I simply let it run until it’s done. All I can conclude is “don’t replace failed disks in RAIDZ arrays with SMR disks that just came out of heavy load and did not have time to flush their cache. To keep the comparison, use the same disk configuration of 4 x 4TB CMR disk in a RAID-5. Guess I should be happy all mine are EFRX as well…, Someone said this is part of a RACE for BIGGER capacities. The later won’t require an adapter, but only some screws. If you watch the video, it’s funny. That 9 day and almost 14-hour rebuild means that using the WD Red 4TB SMR drive inadvertently in an array would lead to your data being vulnerable for around 9 days longer than the WD Red 4TB CMR drive or Seagate IronWolf. That’s for sure! I use ZFS on it, with snapshots, so it actually stores multiple backups. The drives perform terrible ever since day 1, causing the whole PC to appear unresponsive for minutes the moment 1 file in the Steam library is rewritten for game updates. I was under the misapprehension (along with that sinking feeling) from reporting from other sites that all 3TB WD Reds are SMR when in fact there are two models.