Jump to content

NAS Drives: necessary or fluff?


inkblot14

Recommended Posts

I've been running a small home NAS system for a few years now. When I first got it, I loaded it with some WD Green drives, and they've been pretty sturdy.

However, one of them is starting to give me SMART warnings and I'd like to replace it before it brings my little RAID to its knees. Looking around newegg, etc., I'm seeing a class of hard drive that wasn't around when I first setup my NAS: NAS and Enterprise drives. WD and Samsung both seem strong here.

I'm wondering, is a hard drive classed as a "NAS Drive" a significant thing? Is there really optimization that helps a drive survive NAS duty, or is it just a label meant to attract customers? Do any NAS owners have experience with this class of drive, and would you recommend it?

Thanks!

Link to comment
Share on other sites

  • 1 month later...

One main advantage of NAS specific hard drives is that they "give up" trying to read much faster when a bad sector is detected. Standard consumer drives assume a bad sector is the only location of that data piece, so try multiple times in many different ways to read it successfully. However, enterprise or NAS drives in general are part of some sort of redundant array (RAID, ZFS, etc.), and if a sector on one disk goes bad, it's not a big deal, so it quickly marks the sector as bad and rebuilds it from other data. This doesn't slow down the whole array much, and the RAID logic won't mark the whole drive as bad, whereas with a consumer drive the slow down on read time may get the whole drive marked as bad. As Presjar says, the warranty is also part of the cost difference. FWIW though, I've been using WD Green drives without any troubles in RAID array for several years. If super high uptime requirements aren't necessary, you can just tell the RAID controller to have a longer timeout on marking a drive bad, and get away from the problem mentioned earlier.

Link to comment
Share on other sites

  • 2 months later...
  • 2 months later...

Hitachi makes some great drives for NAS that have specs for contiunuous operation and that are the same price as the WD green but at higher RPM. I don't think the NAS classification is a necessity but you should probably try to keep drive specs as close to each other as possible.

Link to comment
Share on other sites

<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <w:DontGrowAutofit/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--> Desktop drives are optimized to be fast on seeks. These causes higher seek retries but significantly higher performance. AAM is usually set to moderate levels or disabled. If they hit an error, they'll try very hard for a very long time to get your data back.

NAS drives are optimized to use less power, cause less vibration, spin slower and always have AAM set to high levels, which multiplies rotational latency. They also do not retry forever to get data back, and just try a few times and then report an error.

You can create a desktop drive from a NAS by disabling AAM, although it'll then reach desktop levels of vibration (which you don't care about) or a NAS drive from a desktop drive by maximizing AAM, but you won't get the early retry termination. In RAID-1 you should care about this, as the array may drop a disk for simply taking too long to read.

<!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} </style> <![endif]-->

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.