Seagate IronWolf Pro 20TB, Enterprise Internal NAS HDD, CMR 3.5 Inch, SATA 6GB/s, 7.200 RPM, 256MB Cache for RAID NAS, Rescue Services - Frustration Free Packaging (ST20000NTZ01)

This review is for the Seagate IronWolf 4Tb model. Amazon groups reviews for drives of varying capacities for the same model family together, so hence the clarification.My first experience of a Seagate internal drive was when I purchased the 8Tb Ironwolf a couple months back (See my review here on Amazon). Since then, the drive has functioned perfectly. That drive is being used in my NAS and since the review of that drive, I have upgraded my 13 year old NAS to a new unit.However, i recently reached a point where I was running low on space on my existing 4 WD Red 4Tb drives, so wanted to add another WD Red 40EFRX model. Searching Amazon and other resellers, I couldn't find this exact model available any more, since being replaced by the WD Red Plus 40EFZX. I wanted matched drives, despite my new NAS using a RAID implementation not demanding this. However, being perhaps old fashioned, I really wanted identical drives.What to do?Well, I could add value to my old NAS by installing the 4 WD Red's I have and sell it. With that goal in mind, I looked to replace the WD's with new 4Tb Ironwolf's. Having been impressed with the 8Tb Ironwolf I have as a stand alone drive in my NAS, I was further tempted by the 20% cheaper 4Tb Ironwolf's compared to the WD Red Plus equivalents, no mean saving when looking to purchase 5 of them!Amazon was selling the Seagate Ironwolf's for just £80 at the time of purchase. This was just too good a deal to ignore, so I purchased 3 of them. Oddly, and something I've never encountered before, Amazon was restricting my purchase to a maximum of just 3. There appeared no stock limitations to account for this, though. That put me in a pickle, but thankfully the wife had her own Amazon account and so I was able to obtain the remaining couple of drives at the aforementioned excellent price.So, how do these compare to my old WD's?Before that, a word on packaging. I've read a few reviews on Amazon complaining about how Amazon ship drives. Be assured that all 5 of the drives ordered, as well as the 8Tb one a couple of months back, all arrived in robust boxes.Perhaps the most surprising thing about these 4Tb Ironwolf's is their size. They are noticeably smaller and lighter than my old WD's. The casing appears slimmer, especially towards the connector end of the drive. They still conform to standards, so will fit into systems, but I'd never seen a drive so noticeably different in its size before. The WD drives definitely feel heavier and more solid, but they are 5 years old, so perhaps use more platters to achieve the same capacity, I'm not sure.I haven't benchmarked these drives, but I understand these Ironwolf's are faster than their WD counterparts and are, of course, all CMR type drives. They also boast an impressive cache size for such a relatively low capacity drive at 256Mb. The newest WD equivalent offers half of that, The Ironwolf also runs around 20MB/sec faster transfer rate at around 200 Megabytes/sec compared to my older WD's.These 5 new drives have all gone through many hours of cloning functions as I sequentially replaced each WD in my array with a new Ironwolf and then an 18.5 hours RAID expansion when adding the fifth drive. All has gone well.These drives run cool and quiet, although they are still noisier than my old WD's. I can hear the seek on these where I was unable to hear anything on the WD's I had before. Nothing major at all, but noteworthy all the same. On a slight tangent, when discussing noise levels, the 8Tb Ironwolf I do have ticks away when idle. It makes a click sound about every 6 seconds or so, so that may bother those seeking a higher capacity model in quiet environments. However, this characteristic is shared with my external 14Tb WD Elements drive, so I believe this clicking is a function of higher capacity drives. The 4Tb drives reviewed here do not exhibit such clicking sounds when idle an spinning.My new NAS now uses a pair of 120mm fans as opposed to the single on the old NAS. This appears to keep drive temperatures nice and low, even the 8Tb 7,200rpm Iron Wolf I was slightly concerned about when running in my old NAS, the temperature differential so far being only an extra 2 or 3C over the 5,400rpm Ironwolfs in the new NAS.For those like me installing these 4Tb Ironwolf's into their Synology NAS's, a word of warning. On my DSM 7.1 system, these new 4Tb Ironwolf's(Model: ST4000VNZ06) appear not to have the Seagate Ironwolf health Management feature available to DSM. The 8Tb IronWolf I have has this feature show up fine in DSM 7.1. As far as I know, IHM (IronWolf Health management) is a feature of all IronWolf drives, but I may be wrong on that front. Either way, if this model does come with that feature, Synology's DSM 7.1 currently cannot recognize it, so you will be limited to only an S.M.A.R.T test option on those.Other than that, those Seagate IronWolf 4Tb drives still offer excellent value for money and, so far, the 5 I have are working fine. As on my 8Tb review, I will update this one should any of the drives fail within, or soon after, the 3 year warranty period.In summary, these 4Tb IronWolf drives offer exceptional value for money along with excellent performance. At current prices, they are a tempting option for those wanting a desktop hard drive in the form of the WD Blue or Seagate Barracuda ranges. You will get superior performance and better reliability with these over their desktop counterparts.

fitted to hikvision dvr and was picked up right away . a quick format and all done. worked perfectly since .its high capacity is welcome as it stores way more days now. its silent in operation so you wont hear it .not as heavy as you would think being so large capacity .you could do worse than this drive . priced well at the time of buying .highly recommended.

I needed this to replace a faulty drive in my NAS. The unit worked as intended and is doing its job by holding my data securely and serving it to me as I need it.

I needed to upgrade the disks in my TerraMaster NAS from 2tb (RAID 1), so, I opted to increase capacity to 6tb.I previously used 2x Toshiba N300 drives. These are relatively quick being 7200rpm but are very noisy. As such, I chose these 6tb Seagate Iron Wolf NAS drives. They are nominally a tad slower as they are 5400rpm devices but, in real life, I see no difference in performance - probably due to a larger on-board cache (256 vs 128mb). They are also very much quieter and the TerraMaster NAS specifically supports the Iron Wolf health monitoring features.The drives arrived well packaged and it was a simple task of inserting them into the NAS and recovering the Volume (one disk and then the other). I then edited the Volume to increase the size to 6tb.The process does take time as recovery was about 10 hours per drive (ie. 20 hours total). Unfortunately, everything went well until a next day catastrophic failure of one of the drives. The device made a continuous hunting noise and was shown as bad by the NAS. The good news was that a call to Amazon product support resulted in a free replacement being sent for next morning delivery and a return label emailed for the bad disk. The new disk arrived as promised and works perfectly - albeit after another lengthy volume rebuild. So, annoying but I can have no complaints about the service from Amazon!Let's hope it was a one-off failure. Time will tell.......Anyway, despite the setback, thus far, I am rather chuffed 😀 😊

The storage device is well-packaged and comes in a capacity of 8TB, which is impressive. The build quality is exceptional, and it operated at a temperature of 40-42 degrees Celsius during my testing. The installation process on my NAS server was straightforward and efficient. Wish it could be cheaper.

As per the title, the IronWolf Pro has long been my drive of choice for performance, and 5 year warranty, though never yet to take advantage of that.Drives are 7200rpm with good cache size allowing then to be used as 'regular' hard drives, particular for offline critical backups.My latest purchase was 5 x 16TB IronWolf Pros for a new Synology DS1522+ NAS. Not on the official drive list but work perfectly. I went for the 16TB as it was the most cost effective whilst also giving me my desired storage.I have the 5 x 16TB drives configured in RAID6 to allow for a double drive failure, giving me 48 TB of effective space. This is over a 5 times increase in storage from my previous ultra reliable Buffalo TeraStations where the hardware never failed but the 3TB drives used in them did, 4 at the worst possible times with cascade failures during array rebuild. Fortunately I had a backup synced NAS, but it took over a week to get operational again.The RAID6 offers a 2 out of 5 drive Parity calculation, and thus fault tolerance of 2 drives failing simultaneously. Just in case, I backup to 2 x 18TB Exos drives on a regular basis.The IronWolf Pros are noisy in use because of their fast seek speed, especially when 5 drives are seeking at the same time. Temperatures stay good on medium cooling option.I have yet to have an IronWolf Pro fail and hope that continues! Recommended!

Great drive at a good price, used in a nas for media streaming. Nice and quiet and quite fast for a traditional hard drive