I'm looking to add an additional drive to my unRAID to add some more capacity. I'm trying to decide if I should replace the parity drive with the new drive and turn the old parity into a data drive, or just add the new drive on. My current setup is a seagate 2TB ST2000DL003 for parity and 2x2TB hitachi 5K3000. This setup has been running for almost 2 years. I'm planning on buying a WD Red. Obviously if I go with a 3TB drive I would have to use it as parity, but I'm leaning towards 2TB at the current price point.

 

So is there any performance hit/gain one way or the other? Am I over thinking this?

 

Thanks,

-Dan

A couple thoughts ...

 

=>  First, you currently have 3 drives.    Are you using the Basic (e.g. free) version of UnRAID?  If so, you'll need to buy a Plus license to add an additional drive [$69]

 

=>  At the moment, a 2TB WD Red is $110 at Newegg ... $55/TB, while a 3TB WD Red is $135 ... or $45/TB.    The 3TB is clearly a better value.

 

I'd buy a 3TB (or even 4TB) and replace your parity drive with that, so you can use the higher capacity drives as you expand your array.    Then just use your current parity drive to add an additional 2TB of capacity to the array (don't forget to upgrade your license to Plus so you can add it).

 

I already have a plus key, so no worries there. The 2TB is actually $99 right now on amazon. Either way, your logic is sound. Makes sense to move up on the parity now.

If you're going to upgrade parity, I'd go with a 4tb because that determines the maximum size of your data drives and it's a long, disruptive process.  Takes several days when you add up the preclear, parity build, and parity check.  Do it once and be done with it.  But that's just me.

 

As for cost, you can walk into Worst Buy and get a 4tb Seagate for $195 (plus tax).  Looks like you can get them for $190 delivered from Newegg.  Not quite the value of the 3tb but close enough for government work.  I just added 4 of those Seagates to my array and they're working well.  You might be able to find the HGST drives cheaper.  I haven't priced those recently...

 

Looks like you can get the external HGST "Touro" 4tb for $160 delivered from B&H.  One of two NYC camera shops I trust.  You'd have to pop the case and get the drive out, of course.