SOHA NAS drives

[tribunal88]

I apologize if this has been covered, but my search came up empty. I'm looking to purchase a NAS appliance sometime in the next 6 months. I'm looking at 8 bays, probably around $1000, with offerings from Qnap and Synology being the leaders right now. I'll be using this for the following tasks.

1) iSCSI partitions for an ESXi host
2) Media storage (Music, home movies, DVD/Blu-Ray ISOs)

The ESXi server hosts a domain controller, web servers, database servers, and a network monitor. I use it for personal servers, but also to test out new tech for my job (I'm a DBA who dabbles in system admin and web development).

I'm thinking either RAID 5 or RAID 10 (I hear rebuild times for 5 are awful), with a hot spare in play with either configuration. Right now I'm not thinking multiple arrays.

With all that information, I'm starting to look at the options for drives. Obviously WD Reds are getting a lot of press these days, but Seagate has NAS offerings as well. I am concerned though, at the high failure rates I see for both companies in these categories. I could go with standard consumer-grade drives, but I'm not sure if those too wouldn't buckle under the stress of a NAS. Similarly, enterprise-grade seems like overkill. I haven't been able to find a lot of information on the web, so I was hoping to get some opinions here.

Thanks!

 

[Cerb]

Not only are the rebuild times of RAID 5 bad, but the burden that puts of the drive has increased the rates of rebuild failure to a point where, unless you need lots of cheap data and no recovery ability (IE, keep a degraded array running until you have time to replace it entirely), you should not use it. IoW, as drive density has outpaced bandwidth, you either have to use so many smaller drives for a big array that your chances of a failure become reasonable, or you have to keep fewer big drives under a near-constant seek load for much longer, increasing your failure chances.

However, hosting OSes, the performance will get you, as well.

The stress the drives go under is 98% marketing, 1% rotation speed, and 1% density. If you're saturating a ~5400 RPM drive's IO capability, a 7200 RPM drive will be faster and more reliable. If you're saturating a 7200 RPM drive, a 10K RPM drive will be faster and more reliable. If you're saturating a 10K RPM drive, a 15K RPM drive will be faster and more reliable. If you're saturating a 15K RPM drive, you need an SSD cache layer. To date, no one not making HDDs has been able to find any significant difference in long-term reliability, nor data error rates, between classes of HDDs, but consistently they find that how the drives are treated makes a big difference (too cold and too hot both increase failure rates, FI).

Reds, REs, and their ilk, should be used for RAID implementations that are not friendly to consumer drives without TLER.

 

[smitbret]

RAID 5 is fine for home use. Consumer drives are probably just fine, too. If you are really paranoid, set up RAID 6 so you can handle 2 simultaneous drive failures.

As far which drives to use, Backblaze just did some time/failure research that showed that consumer drives have no higher failure rate than enterprise drives. My personal experience would agree. If you are using a hardware RAID then stick with the NAS drives like the WD Red or Seagate's NAS offerings otherwise you'll end up trying to figure out why your drives keep dropping out of the array.

If this is a professional or business environment, then disregard everything I just said and hire someone to set you up with an enterprise rack mount or professional grade system.

 

[tribunal88]

If this is a professional or business environment, then disregard everything I just said and hire someone to set you up with an enterprise rack mount or professional grade system.

I don't think it rises quite to that level of necessity. I use it for proof-of-concept testing because it's faster to spin up my own VMs than wait for the sysadmins to get me one on the development cluster. Also, sometimes I need to mess with the domain controller to conduct tests that integrate with enterprise security, and again, that's not something I'm able to do on the development environment.

In either case, it sounds like I'll need to go with WD Reds or Seagate NAS drives and as far as failure goes, you pays your money, you takes your chances.

Thanks for the tip on TLER. That's good information I didn't have before, and certainly reduces the choices available.