Re: Western Digital Red 4 TB: Any Hope for Ultra-6 HCL?
StephenB wrote:
You are aware of the expansion limits?
"Aware" might be unduly optimistic.... but I come away from skimming various threads with the impression that I could get 14 TB/dual redundancy just by substituting new 4 TB drives one-by-one and 16 TB by wiping the array and reloading it from scratch.
Am I even close?
If so does (14-10)/4 = 400 gigs per drive hold up if I just want to substitute one or two drives?
Re: Western Digital Red 4 TB: Any Hope for Ultra-6 HCL?
There are two limits, and they both apply to the actual volume size, not the raw disk capacity.
One limit is that you can't expand from < 16 TiB to > 16 TiB in any circumstances. You could get 20 TB in the ultra-6 anyway (single redundancy) by doing a factory reset with all drives in place. Or 16 TB with dual redundancy. Further expansion is not possible.
The other is that a volume cannot grow more than 8 TiB from its starting point. So if you started with 2x1TB on your initial install you'd have a 1 TB volume starting point. The growth limit would take you to a bit more than 9 TB. So you wouldn't get to 14 or 16 in that case. I don't know what you actually had installed when you did the original installation, so I don't know what your actual growth limit is.
Re: Western Digital Red 4 TB: Any Hope for Ultra-6 HCL?
StephenB wrote:
The other is that a volume cannot grow more than 8 TiB from its starting point. So if you started with 2x1TB on your initial install you'd have a 1 TB volume starting point. The growth limit would take you to a bit more than 9 TB. So you wouldn't get to 14 or 16 in that case. I don't know what you actually had installed when you did the original installation, so I don't know what your actual growth limit is.
Thanks.
I don't remember my initial config... I want to say it was a full house of 2-TB drives, but wouldn't bet the mortgage money on it.
My take-home from this: Try a couple 4 TB drives... see what happens... and be prepared to do a factory reset.
Tangentially: I am thinking that dual redundancy might be overkill for somebody who has current backup. Could I drop back from dual redundancy to single redundancy without resetting? i.e. just flip something, let it churn for awhile, and come back to increased capacity?
Re: Western Digital Red 4 TB: Any Hope for Ultra-6 HCL?
You cannot convert a dual-redundant volume to a single-redundant one. You would need to backup your data and do a factory reset (wipes all data, settings, everything).
Re: Western Digital Red 4 TB: Any Hope for Ultra-6 HCL?
Try downloading the logs, and looking in expansion.log for the first occurrence of "Data volume has been successfully expanded". If the date matches your first install that should tell you.
If you did start at 6x2TB dual redundancy, you can expand up to 16 TiB, so 6x4TB should be fine.
But unfortunately dropping back to single redundancy means a reset.
As far as I can dope it out, the diff seems to be something around vibration tolerance - the more drives in a box, the greater vibration tolerance required - so the cheaper one should suffice for my Ultra-6.
As far as I can dope it out, the diff seems to be something around vibration tolerance - the more drives in a box, the greater vibration tolerance required - so the cheaper one should suffice for my Ultra-6.
Am I even close?
The WD4001FFSX is part of the WDC Red Pro line, the WD40EFRX is part of the WDC Red line.
The most important difference is that the FFSX runs at 7200 rpm. So it is higher performance. The EFRX runs at ~5900 RPM - not as fast, but runs cooler/uses less power. The FFSX has a 5 year warranty, the EFRX only has a 3 year warranty.
