Hitachi 2TB 5K3000 - RAID size discrepancy

[aphasia]

i bought 3 Hitachi 2TB 5K3000 HD's yesterday which i want to setup in RAID 5 on my NAS. posted thread on topic here;
http://hardforum.com/showthread.php?p=1036882803#post1036882803

but there is a small discrepancy on full capacity on 1 of the drives of around 8MB.
was wondering if i should return the drive? is the small size difference going to be an issue when installed in RAID5 array?

thoughts?

ok on to basic info on the hitachi drives in windows;

yep, all disks present and accounted for.

hmmm... slight discrepancy on formatted size on disk '0' (D:\) compared to disk '2' (E:\) & '3' (G:\)...

wtf, i'm missing 8228864 bytes or 8 MB... it's like disk '0' (D:\) doubled up on the 'unallocated' space at the beginning of the drive.

partition wizard shows the 'unallocated space' is the same across the 3 hitachi drives.

now i'm confused.
i've finished the benches, bit of variance there as well. not sure if the results fall outside the margin of error though. will post shortly.

 

[aphasia]

bump...

anyone?

 

[HICKFARM]

I don't think the 8mb should make a difference. Odds are you just had a bad sector or something and now it isn't using it. Raid will just use the smallest of all the harddrives so you will just just be out of luck for 8mb for every drive. If anything run the hitachi fitness tool. I just got 5 of those drives in the mail earlier today and ran the test on one of them. Took forever, around 5 hours at least for a single drive. But it might be worth running once for you on the questionable hard drive.

 

[aphasia]

you're probably right regarding the bad sector.
i've sent an email off to hitachi anyway so i'll see what happens.
with the DFT, what media did you use to boot off?
if you used USB drive, what tools did you use to make bootable?

 

[omniscence]

Is it possible that one of the drives has a host-protected area (HPA)?

 

[aphasia]

had to loop-up HPA.
i guess it's possible, but why do it and for 8MB?
what's the best (free) software to check for hidden partitions?

 

[aphasia]

currently running the DFT on my hitachi 2TB drive with the missing capacity.
since i have no CD/DVD or floppy drive to run the fitness tool in dos, using the DFT image on a bootable USB flash drive.

found a great little program that can mount all your CD/DVD boot images off a flash drive. you get a boot menu once loaded and select whatever image is required.

Boot Multiple ISO from USB (MultiBoot USB)
http://www.pendrivelinux.com/boot-multiple-iso-from-usb-multiboot-usb/

fantastic program, no need to hang on to those boot CD/DVDs anymore, real keeper.

 

[aphasia]

finished the 'Drive Fitness Tool - advanced test' on my hitachi 2TB with missing capacity, no problems.

now i'm at odds, i have three supposably identical drives that work without problems except 1 drive is missing some space.

i ask this (to those who use lots of disks for RAID & can still bothered to read this thread ), if you bought a bunch of identical drives and 1 or more came up a little short on space, would you return it?

 

[Blue Fox]

They're all technically bigger than advertised, so why return them? I personally have my RAID card round down to the nearest 1gb increment to account for any discrepancies.

 

[aphasia]

ok, but doesn't a RAID array automatically do this by itself, round-down to the smallest disk.

my old NAS (still functioning) has 5 identical segate 750GB (ST3750640AS) that list the same amount of space, 715,404 MB. and these disk weren't all purchased at the same time nor have the same firmware (3.AA vs SD45).

my fear is this, one of my disks is a little short, does this mean it'll have problems later down the track? if you bought identical disks and 1 was off, does that raise a flag? if others have done this and have no issues with the disk(s) in question, i'll accept that and not worry about it.

 

[Blue Fox]

Yes, but if were to get a fourth disk that was slightly smaller (but still over 2TB), you wouldn't be able to rebuild the array with it. There really isn't a problem with your disk though. Nothing out of the ordinary.

 

[aphasia]

thanks for your input Blue Fox, fair point if i were to get another disk that was smaller and not being able to use in existing array. even more important as i have 2 slots left in my new NAS.