MyBookWorld NAS and Samsung 1.5TB external usb drive file copy issue

[satma]

I'm using a Macmini on OSX 10.5.8.

I have a WD 1TB MyBookWorld Network drive connected to my router which works perfectly with several macs connected to the router.
I bought a Samsung 1.5TB external drive to expand the storage and connected it to the usb socket on the MyBookWorld.
It is recognized as 2 USB share disks, one with 196meg capacity and the other 1.36TB for some reason.

However the problem arises when copying a folder to the Samsung.I get an error code 50.It copies the title folder but then I have to manually copy the contents to it which takes time.

Single files copy fine, only folders present this problem.

When the Samsung is connected directly to the Mac, it works fine.It only happens when connecting it to the network drive.

Any ideas how to rectify this?

 

[rsacorp]

Hard to say, but here's my two cents:

First, the difference between USB drives and network drives:

* USB drives are nothing more than a hard drive connected by other means. Instead of an internal SATA/PATA connection, the drive connects via USB. All calls to the hard drive work essentially like any other drive connected to your computer; Mac OSX communicates with the drive.

* Network drives are designed to be independent, so they need to have their own operating system built-in. Most commonly, network drives use a stripped-down version of Linux to handle all calls to the drive.

In your case, when you connect the drive to your Mac directly, Mac OSX handles all the communications to the drive - whether it's HFS, NTFS, or FAT32, Mac OSX handles the formats. When you connect the external drive to your network drive, the Linux distro on the network drive is the one that talks to the network drive, not your Mac. Essentially, the Mac talks to Linux, which talks to your external hard drive.

Here's the kicker: all USB drives are similar, but they are not identical - there are subtle differences that most people don't see. Drive manufacturers optimize their devices to talk to other devices they manufacture, but not necessarily other manufacturers' drives. So your WD net drive SHOULD work with your Samsung, but not a guarantee.

I can only theorize, but it sounds like either the USB driver on the WD network drive does not work 100% with the Samsung drive. Sounds like the permissions are not transferring correctly on the WD drive over USB (error code 50, which is frequently seen copying from remote drives to your Mac). See

http://support.apple.com/kb/TA20831?viewlocale=en_US

for more info (it's on OSX 10.1, but the issue is the same.

I am also not one that usually recommends external USB drives on any NAS, for exactly this reason. I have yet to see one that works flawlessly.

You can try the following:

* Update the firmware on the NAS. You can download it from Western Digital's website. That may solve the issue - many of these issues are reported to WD, and fixed by their code monkeys.
* If you can, see if you can get a friend's WD USB drive and try to duplicate the problem. If the problem goes away, then the issue is the compatibility with the Samsung drive.
* Consider scrapping the USB drive idea, and upgrading the drives themselves. Western Digital's site has a great document on opening the chassis, and replacing the internal drives - the only catch is that they must be WD Caviar Green drives. If you have the original manual, the instructions will be there as well. For more details, go to:

http://www.wdc.com/wdproducts/library/UM/ENG/4779-705013.pdf

Hope that helps...

Mike Molenda - TAC Analyst


RSA Corp - Houston, TX
Technical Assistance Center

http://www.rsacorp.com