[PLUG] SD cards always mount read-only

Jason Bergstrom bergie at bergie.net
Wed Oct 12 02:28:02 UTC 2011


> On Tue, 11 Oct 2011 09:01:49 -0700
> John Jason Jordan <johnxj at comcast.net> dijo:
> 
> >It would be interesting to try it in laptops running other distros.
> >However, I did try live CDs of Lucid and Knoppix with and it was always
> >read-only. And my GRML rescue CD also saw it as read-only.
> >
> >By the end of the day I hope to know how it mounts on a Windows
> >laptop.
> 
> So today I went to PSU for class and took the SD card with me to see
> what happened on Windows computers. First I went to the graduate
> computer lab in the basement of Smith. They have some <very nice> Macs
> which have an SD card reader built in, whereas for the Windows
> computers you need to go to the support desk and check out a USB SD
> card reader. I opted for the Mac.
> 
> The Mac mounted it automatically, and it was read-write. So (after
> fumbling around the Mac GUI) I found a utility to reformat it.
> Unfortunately, the only choices were several different Mac filesystem
> formats plus "FAT (MSDOS)." It didn't even say what flavor of FAT, nor
> did it have any option to make it bootable or other choices. I went
> ahead and formatted it FAT, and it finished without incident.
> 
> I had to go to class, but later I came back and tried the USB SD card
> reader with a Windows computer. This offered me FAT16, FAT32, NTFS and
> something else (forgot). I decided to format it NTFS just because I
> thought that it might be more likely wipe any evil stuff that SanDisk
> had put on the device. It finished the formatting without incident.
> 
> I was unable to find any Linux computers on campus that I had access
> to. Not being a computer science major I am not allowed to use
> computers in the CS department.
> 
> I am now home. I put the card into my Fedora 14 Thinkpad and got it
> recognized, even though it was NTFS. Using Gparted I attempted to
> format it, but I got the same error message as before: The device is
> read-only.
> 
> There remain three possibilities:
> 
> 	1) The card reader in the Thinkpad is flaky
> 	2) The adapter is flaky.
> 	3) Linux is flaky.
> 
> Further testing will require finding a Linux computer that has an SD
> card slot (capable of > 4GB), and that is -Thinkpad, -Fedora. In the
> meantime, does anyone else have an SD card that is working in a Linux
> computer?

I have both, a card (16G Kingston), and a Vaio with a card reader.

You are welcome to exchange cards for testing.

Jason,
bergie at bergie.net



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