Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

bounou

macrumors 6502
Original poster
Jun 6, 2012
354
110
My pegasus2 is not recognizing any of the drives i try and use with it, i get a message when i click on the physical drive list that says "no physical drives in the enclosure".

I tried with 3 different types of drives, WD caviar green 2TB, WD caviar green 1TB and an old 500GB samsung drive i had lying around. All of the drives are formated Mac OS X Extended (Journaled).

What am i doing wrong?
 
That's not much of a list for compatibility! Basically only current generation drives are listed, as that is probably what Promise used for testing.

I would think the WD Green drives would at least be recognized, whether they worked well or not.

"Green" drives are generally not recommended for hardware RAID systems, possibly due to variance in becoming "ready" within the time frame necessary to avoid being voted out of the array by the hardware controller. I believe they will work in some of the software RAID-like systems where the timing isn't as critical.
 
That's not much of a list for compatibility! Basically only current generation drives are listed, as that is probably what Promise used for testing.

I would think the WD Green drives would at least be recognized, whether they worked well or not.

"Green" drives are generally not recommended for hardware RAID systems, possibly due to variance in becoming "ready" within the time frame necessary to avoid being voted out of the array by the hardware controller. I believe they will work in some of the software RAID-like systems where the timing isn't as critical.

How big of a deal is it? Should i bother returning these and getting barracudas?
 
How big of a deal is it? Should i bother returning these and getting barracudas?

WD Greens are terrible for RAID and NAS use. They spin down after 8 secs (or so) if not polled by the controller, and some controllers are setup to poll the drives every 10 seconds...

You'll soon see your drives has started/stopped hundreds of thousands of times, and if there's one thing mechanical drives doesn't like, it's the start and the stop.

One of many discussions on this problem: http://forum.synology.com/enu/viewtopic.php?f=124&t=41481
 
How big of a deal is it? Should i bother returning these and getting barracudas?

I haven't used the Pegasus2 models personally, my experience was with a OWC Mercury Elite Pro Qx2 RAID-5 box some time ago (I now have 3 of these in use here). I initially used WD Green 1TB WD10EADS drives in the box and although it worked, occasionally it would show drive error indicating a disk needed to be replaced. Restarting the RAID box restored normal operation, and it wasn't always the same disk drive showing the error. I replaced all 4 drives with standard 1TB drives and haven't had any problems since.

Here is what OWC says about drives:
http://eshop.macsales.com/item/OWC/M3QX2KIT0GB/

Note: Regardless of drive model used, OWC requires that all drives used match exactly for proper RAID operation.

**NOT RECOMMENDED**
Seagate Barracuda 7200.11 series - all models, particularly the 1.5TB 7200RPM model p/n ST31500341AS due to stability and performance concerns.

Western Digital Green drives - all models, due to potential critical operational issues attributed to the IntelliPower technology providing inconsistent variable transfer rates.


FWIE: I currently have some WD Green 2TB drives running in software RAID-0 in a Mac Pro with no problems. I also used the above mentioned 1TB Green drives in a HP MediaSmart Home Server (software RAID-like file duplication) without any problems.

If I were spending the cash for a Pegasus2 looking for maximum speed ... yes, I would return the Green drives and get WD Red drives.


-howard
 
OS version?

I found a problem with older versions of OS X. I had a problem with my Pegasus2 4-bay not being properly recognized when running 1.8.3 on a 2012 iMac. When I booted from a 10.9.1 install with the same hardware, no problem.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.