Hello, Iām relatively new to self-hosting and recently started using Unraid, which I find fantastic! Iām now considering upgrading my storage capacity by purchasing either an 8TB or 10TB hard drive. Iām exploring both new and used options to find the best deal. However, Iāve noticed that prices vary based on the specific category of hard drive (e.g., Seagateās IronWolf for NAS or Firecuda for gaming). Iām unsure about the significance of these different categories. Would using a gaming or surveillance hard drive impact the performance of my NAS setup?
Thanks for any tips and clarifications! š»
One thing that would be useful to understand is the distinction between CMR and SMR
As you are looking for bulk data storage, the driveās speed isnāt of too much concern. A 5400RPM drive is plenty.
If you are looking to put this drive into an array with other drives, make sure you get a CMR drive as SMR drives can drop out of arrays due to controllers finding them unresponsive. If a drive does not list it is CMR, itās best to assume it isnāt. Seagate has a handy CMR chart, for example.
Additionally, if there are multiple spinning drives in the same enclosure, getting drives with vibration resistance is a good bonus. Most drives listed for NAS use will have this extra vibration resistance.
Is this for hardware RAID controllers, or have you experience software RAID like LVM or ZFS exhibiting the same drop out behavior? I personally havenāt but it be nice to look out for future drives.
I have not personally experienced a dropout with a SMR drive. That is from the reporting I saw when WD was shipping out SMR drives in their Red (NAS) lineup and people were having all kinds of issues with them. According to the article (below), it sounds like ZFS has the worst time with them. WD also lost a class action suit over marketing these as NAS drives, while failing to disclose they were SMR drives (which donāt work well in a NAS).
We want to be very clear: we agree with Seagateās Greg Belloni, who stated on the companyās behalf that they ādo not recommend SMR for NAS applications.ā At absolute best, SMR disks underperform significantly in comparison to CMR disks; at their worst, they can fall flat on their face so badly that they may be mistakenly detected as failed hardware. Source
I remember this - I had just bought my second drive for my nas (raid1, original drive cmr), and it was performing like shit. The next day, news broke about this bullshit and a couple days later, the suit was started. I was fucking pissed, the drives were still having trouble, with terabytes of irreplaceable data at risk while the two drives struggled to mirror. I got in contact with wd and after some back and forth bullshit, I straight-up threatened to join the class and blacklist wd for all my personal, family/friends, and clientās builds, if they didnāt rma the drive immediately and send me a cmr replacement. Iāve been 100% wd for over 20 years, and I have decent reach as to what I recommend and buy for people.
They sent me a cmr drive via express shipping. I continue to buy wd drives (two more disks in that machine, an external backup, an internal desktop pcie raid0 nvme+card, an internal backup drive for my desktop, a backup ssd for one of my laptopsā¦), but with much more scrutiny. I did not join the class, but itās still a black mark in my book. Iāve been thinking about giving Toshiba a whirl, their drive reviews look good. Maybe next upgradeā¦
Also remember that your parity has to be more or equal to the biggest drive in your array. If you buy a 10 but donāt have another 10 you must use the 10 as parity.
The concern for the specific disk technology is usually around the use case. For example, surveillance drives you expect to be able to continuously write to 24/7 but not at crazy high speeds, maybe you can expect slow seek times or whatever. Gaming drives I would assume are disposable and just good value for storage size as you can just redownload your steam games. A NAS drive will be a little bit more expensive because itās assumed to be for backups and data storage.
That said in all cases if you use them with proper redundancy like RAIDZ or RAID1 (bleh) itās kind of whatever, you just replace them as they die. Theyāll all do the same, just not with quite the same performance profile.
Things you can check are seek times / latency, throughput both on sequential and random access, and estimated lifespan.
I keep hearing good things about decomissioned HGST enterprise drives on eBay, theyāre really cheap.
Apart from the SMR vs. CMR, if your NAS will run 24/7 you need to make sure to use 24/7 capable drives or find a way to flash a 24/7-specific firmware/setting to a consumer drive. Normal consumer drives (e.g. WD Green) tend to have a lot of energy saving features, e.g. they park the drive heads after a few seconds of inactivity. This isnāt a problem with normal use as an external drive that only gets connected once in a while. But in a 24/7 NAS the drive will wake up lots of times and park again, wake up, park again ā¦ and these cycles kill the drive pretty fast.
https://www.truenas.com/community/threads/hacking-wd-greens-and-reds-with-wdidle3-exe.18171/
