I'm looking for a little advice, server has been up and running for a whole week and I've already acquired 4x hard drives from some eBay wheeler dealing to get myself some initial storage.

 

I started with a 1tb Samsung and a 640gb WD Blue mainly for testing purposes. Foolishly I put both of these on the 2x available SATA III ports on my board. I've used the 640 WD for data and the Samsung as parity.

 

So my board has 2x SATA III and 6x SATA II, so 8 ports total. I am now in possession of the following drives:

 

1tb Hitachi deskstar SATA III (I'm thinking this as my new parity drive)

500gb Hitachi Deskstar SATA III (I'm thinking of using this for a cache)

500gb Hitachi Deskstar SATA III

1tb Samsung Spinpoint F1 SATA II (my current parity)

640gb WD Blue SATA II (has some data on)

500gb Seagate Barracuda SATA II

 

Now I know that a standard hard drive struggles to utilise a SATA II bus, however I'm thinking to offer the server the best performance I would like my Parity and cache drive on my SATA III controller and my data on the 6x SATA II controller. This basically means I need to change the ports on both my existing drives and change the role of the Samsung. Now I have put quite a bit of data on the available drive, I have it backed up of course so worst case scenario is I can start from scratch. My question is can I move these drives around without wiping the data from the current 640gb drive?

Current unraid versions do not rely on port connection to identify logical slots in the array, so you can move them around to any controller you want and unraid should find them.

If I basically stop the array and then remove the drives from it, will unRAID allow me to put the 640gb drive back into an array with already populated data? Or will it force me to format it?

Physically moving the drives from port to port will not remove them from the array. As long as unraid can find the drive somewhere in the system, it will stay assigned the the same array slot and nothing will change with your data.

 

You will want to properly shut down the array before you change connections. Hot plugging is not advisable, as too many things could go wrong.

 

If I were you, I'd physically mount all the drives where you want them in the case, and connect everything exactly the way you want it. Before you start changing logical array assignments, I'd run at least 1 preclear cycle on all the newly acquired drives, mainly as a testing routine to ensure you don't have any questionable drives in the mix. Unraid requires all remaining drives to be read perfectly to reconstruct any single drive failure, so you don't want any borderline or questionable drives in the array.

Two things:

 

1)  As jonathanm noted above, it makes no difference which SATA ports you plug your drives in.  UnRAID tracks them by serial #, so you can freely change where you plug them in.

 

2)  It's also completely irrelevant where you plug the drives in -- e.g. SATA-II or SATA-III.  BOTH of these ports have interface rates FAR above the capability of any modern drive, so the sustained transfer speeds will be the same no matter which interface is used.    The only thing you'd need to be sure and use a SATA-III port for is an SSD, which it's no likely you'll be using unless it's for your cache drive.    By the way, if you're using a traditional drive for a cache (as you indicated), you'll get notably better performance if you use the drive with the highest areal density for this.  Without model #'s, it's impossible to say which of the drives you listed would be best.

 

 

 

By the way, if you're using a traditional drive for a cache (as you indicated), you'll get notably better performance if you use the drive with the highest areal density for this.  Without model #'s, it's impossible to say which of the drives you listed would be best.

 

 

Please do expand on this, as I've mentioned I'm pretty new to the game. The drive model numbers are:

 

Hitachi Deskstar 7K1000.D

Samsung Spinpoint F1 HD103UJ

Western Digital Blue WD6400aaks

Hitachi Deskstar P7K500

Seagate 7200.10 ST3500630AS

 

Thanks!