Updates

• July-2024 (5 month) update - no failures on any drives.
• August-2024 (6 month) update - still no failures on my drives from tech on tech, but I had another of my original Seagate Exos NAS drives fail - that’s now a 100% failure rate in less than 4 years.

I recently had a drive failure on my NAS. While not a big deal with RAID-6, it wasn’t the first in that array, and the array as a whole was more than 3 years old. I figured with 2 out of my original 3¹ drives failing, and wanting a bit more horsepower on my NAS, I would just replace the whole thing.

The last time I rebuilt my NAS, I bought brand-new Seagate EXOS 14TB drives, but with two failures in three years, I decided to not use drives from that series again. New 16TB drives were running about $300 - $350 at the time I checked.

Amazon is reselling “Refurbished” (aka “used”) Western Digital Ultrastar DC HC550 under their “Amazon Renewed” brand from a company called Tech on Tech for $170, or about half what the new drives cost. The drives come with a two year seller warranty from Tech on Tech (new drives usually have a 3- or 5-year OEM warranty.)

So, are these drives any good? Well, I bought some 14TB HC 530s from them around 9 months ago, when my first Seagate drive failed. From a sample size of 2, no problems so far. The new drives have been running for about a month, with no problems yet. But, still, far too early to tell.

I do wish companies would call these “recertified” or “remarketed” or just “used drives”. That is what they are. There’s no way any of these companies (including the OEM) are meaningfully “refurbishing” these drives. At best, they check them, slap a new label on them and, almost always, seem to reset the SMART data so you can’t tell how old the drive really is.

But, they cost 1/2 of new.

With RAID-5 I wouldn’t use a refurb drive. But, with RAID-6, I’m willing to take a little more risk since I can take two drive failures before risking data loss. A RAID 5 array with 4 brand new drives would cost me almost $1,300. With the refurb drives, 5 of them only cost $850. My expectation for this array is for it – and my NAS hardware – to last four years. I’ll update this post from time to time with any failures, updates, observations, etc.

There’s an interesting Reddit thread here in which a representative from Server Part Deals (same company as Tech on Tech, different brand) answers some questions. Two things caught my eye:

First, Server Parts Deals/Tech on Tech claim it is the OEMs who are resetting the SMART data on these drives (not very practical knowledge, but I always assumed it was the resellers)

Second, they quoted some verbiage from Seagate on the reman process and source of these drives. At least, the refurbished Seagate drives they sell. It is, unsurprisingly, from warranty returns. They state:

A significant percentage of drives returned to Seagate are determined to have No Trouble Found (NTF). These drives are separated from the rest for a faster recertification process. The rest of the drives are shipped back to Seagate factories for evaluation and repair. In the case of SATA interface NTF drives, Seagate uses the ATA SECURITY ERASE UNIT command, Enhanced Mode, as recommended by NIST 800-88 and ISO/IEC 27040. After media sanitization, the drives are relabeled and marked as Certified Repaired HDD drives.

Now, I don’t know what their defect rate is, but at other hardware manufacturers where I’ve worked, the NTF rate hovered around 70%. Meaning two out of every three devices returned by customers as defective tested out just fine. The normal process for testing returned parts is to run the manufacturing test suite and if the device passes, it is marked good. What isn’t stated above is that these tests are never perfect, and so it is also common to have something like a three-strikes rule, where if an individual part gets returned, say, 3 times, that part is pulled from the RMA/refurb pool.²

That these drives are probably previously RMA’d to the OEM doesn’t bother me at all. Customers return stuff that isn’t defective all the time.

On warranties

Warranties, of course, are no good if the company behind them folds or refuses to honor the warranty. First, I’ll say that dealing with drive OEMs on warranty returns – if you’ve never had the experience – is painful. It can take a long time to get a replacement drive from them. Last year, when my Seagate drive failed, it took around three weeks to get a replacement. That’s a long time to have your RAID array in a degraded state. I tried to find examples of people having problems with Tech on Tech’s warranty return process, and I couldn’t. I saw people complaining about having drive failures – which, again, see my Seagate experience, happens even with new drives. I also saw people that seem to think there is something inappropriate about a company having a few marketing brands. But nothing about bad warranty experiences. In fact, what I could find were positive experiences: here and here. From all indications, Tech on Tech is a reliable and honest reseller.