HDD Selection

[KarylFStein]

I’m planning my next server refresh and think that I will go with two unRAID servers. I usually do a refresh over the Christmas break so have some time, but am starting to pick out hardware as this will be a bit of a change and want to spread out the purchases.

The first hurdle which I thought would be easy is storage. In my current Win10/unRAID setup I already have dual SSDs as the OS/cache drives and will retain those. I’m also maintaining the motherboard/CPU/memory/cases/backplanes. Even though some of those are a few generations old they do the job.

My main server has 8 SATA ports with 4 of those being SATA 6. I could get an SATA card and a 4-in-3 3.5” drive enclosure to push that to 12 drives total to match unRAID licensing, but why?

The problem is the HDDs to get. Cache is SSD. Parity is HDD and needs to be as fast as pool drives. I’m stuck between Seagate, Toshiba and WD. I have had bad experiences with Seagate and WD in the past. Toshiba seems like a no-brainer as I have one of their drives in my system now and it works well, (and the NAS option is the cheapest), but it seems to be middle ground with performance and warranty. For parity I’m looking for fast and will get a couple of them.

[JustFred]

You might want to also consider HGST-branded drives. Even though WD bought the Hitachi/HGST disk division a couple of years ago, HGST-branded drives still come from an independant HGST design team. My impression is that WD tends to produce consumer-quality stuff, while HGST leans towards the enterprise class. One of the benefits of living & working in the heart of Silicon Valley is access to some lesser-known info, but I haven't recently asked my resources whether both are produced in the same factory, so can't comment on that.

Here's some useful statistics about drive reliability based upon thousands of drives in actual use (as opposed to superficial online reviews and/or anecdotal reports). Their results align with my (rather limited) experience:
https://www.backblaze.com/blog/hard-...rk-stats-2016/

You might not be inclined to read all the comments at the bottom of the article, but don't miss the "Survival analysis of hard disk drive failure data" here: http://bioinformare.blogspot.com.au/...isk-drive.html

[Fuzzy]

I think in general, you'll find that drive performance, in practice, will not end up being all that important or noticeable in an unRAID based SageTV server. Read speed on even the slowest drives on the current market is going to be plenty fast enough to serve up multiple streams to multiple clients simultaneously without issue. Write speeds are of minimal importance, because of the way unRAID uses the cache disk (recordings to cache, and then moved to spinning media later). For this reason, I think large capacity, low RPM drives, are probably the best bet. Lower speeds means less heat, and less heat generally means longer life. I can't speak to a certain brand or model, as I've had a large variety of drives in my servers over the years, and have had very few failures, and those on drive over 5 or 6 years old. Most of my drives have been retired due to space, not failure.

[KarylFStein]

Originally Posted by Fuzzy

I think in general, you'll find that drive performance, in practice, will not end up being all that important or noticeable in an unRAID based SageTV server. Read speed on even the slowest drives on the current market is going to be plenty fast enough to serve up multiple streams to multiple clients simultaneously without issue. Write speeds are of minimal importance, because of the way unRAID uses the cache disk (recordings to cache, and then moved to spinning media later). For this reason, I think large capacity, low RPM drives, are probably the best bet. Lower speeds means less heat, and less heat generally means longer life. I can't speak to a certain brand or model, as I've had a large variety of drives in my servers over the years, and have had very few failures, and those on drive over 5 or 6 years old. Most of my drives have been retired due to space, not failure.

Oh, right, I forgot about the cache . I don't expect to have more that four streams at once. It'll also serve NAS duties, but pulling large files off of it is rare.