Sunday, 19 January 2014

Linux Mint External Hard Drive Read Only

I tried to create folders and copy files to an external hard drive of mine.

Actually, it's not an external hard drive. It's a hard disk caddy that I plug SATA drives into.

It's one of these unbranded Chinese models. Sadly, there doesn't seem to be a reputable brand making these, not that I've seen anyway. Even in Windows XP it can be a little troublesome and require replugging or power cycling.

But for Linux, I can read from it fine but I cannot write to it at all.

I heard it could be due to an old ntfs driver so I searched the Software Repository for "ntfs-3g" but saw it was already installed and presumably being used.

By the way, I've had no such issues with USB memory sticks.

I also tried right-clicking and "Open Folder as root" but this didn't work either. I just couldn't write to the drive. Sometimes I'd get "input/output" errors.

I guess this device is just incompatible with Linux. That's no big deal really. I have other, proper external hard drives.

I've got to admit though, I'm a little worried about the way Linux handles external devices, especially those of FAT32/NTFS format. In doing my research, I've read some horror stories about it scrambling existing data!

In the end, I inserted a USB stick with data on it that I didn't care about and copied the files. I had a chance to use the terminal command "cp" to copy across. I then ran md5sum to check that the files had been copied perfectly.

In fact they weren't! One of them, a big one around 1 gig, was not copied and I got different MD5 checksums! I copied it again using the GUI and had the same problem! I tried replugging the USB stick and I got read only errors again! Finally I replugged it once more and could write to it again, copied with the gui once more and the checksums failed. I tried again with the cp command and FINALLY the MD5 checksums matched!

Why these MD5s did not match, I do not know. I have heard that Linux likes to use write caching a lot. So you think the file has been copied but it's still really just catching up...who knows?

Perhaps there are better ways to do all this. I am treading on new ground, after all. Best I don't become TOO reliant on Linux just yet...! Oh, I miss Windows XP already! :D

No comments:

Post a Comment

Popular Posts