There may be a lot of people out there who are suffering unnecessarily because they are using drives that are not compatible with NAS raid devices.
This is because dealers selling the NAS units know nothing about the way NAS systems operate.
My company has been doing some research on this matter for a couple of months and tested a whole range of NAS units. They ALL suffer with the same problem! They do not tolerate new technology that effectively fools “platters” in a disk that there is more space on it than it really has.
For instance, Western Digital is a good example with its Advanced Technology Format.
Advanced Format technology enables hard drive companies to read and write more data onto the same available space on the hard drive.
Advanced Format technology is being adopted by WD and other drive manufacturers to increase media format efficiency, thus enabling larger drive capacities…basically any drive that has migrated to 4K sectors should be avoided.
These typically “desktop” drives are really only made for Windows applications and associated formatting. They are not tolerated in UNIX/Linux based raid systems. In fact, as an aside issue, they will cause alignment problems for most users of any operating system less than Windows 7 (although some people might argue with me on that issue)…Microsoft has at least conceded that it will be an issue for XP.
You might get them formatted but find that down the track they will degrade to the extent that you can’t find a file, you can’t delete a file and find that copying copious amounts onto the system becomes impossible.
The best thing to do is to make sure that you research the types of drives before you buy a NAS device otherwise you might end up with drives that don’t work in the long run.
Here is a list of Western Digital that I know have this technology and should be avoided …
WD Caviar Green Desktop Hard Drives
640 GB WD6400AARS
800 GB WD8000AARS
1 TB WD10EARS
1.5 TB WD15EARS
2 TB WD20EARS
WD Scorpio Blue Mobile Hard Drives
750 GB WD7500KPVT
1 TB WD10TPVT
If you already have one of the above drives (typically ‘EARS’ series) you might try the following but make sure that your files are backed up.
Install a 2.54MM type jumper on pins 7 & 8 before installing the drive into a NAS system.
This puts the drive into compatibility mode.
This should improve performance in a NAS system since the partition starting on sector 63 is then fooled into using a sector (64) aligned on the 4k boundaries.
WARNING ! Installing a jumper on a drive that already contains data will likely result in data loss so back up your files first.
I have succeeded in doing this and have had file integrity for a couple of months. But as a professional system integrator and engineer, I will not recommend this to any of my clients.
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Topic: Western Digital Advanced Format Drives - Read before you buy! (Read 187755 times)