SD card suddenly became read only

[suruaZ]

I nothing changed in the System or with SD card. It was inserted and I had read-write access. But now it became read only? I tried to re-mount it, but again and again it mounts as ro  

Any ideas what's going wrong?

Thanks,
suruaZ

[tz]

You probably have a filesystem error - you need to run chkdsk on a PC, or fsck.vfat if it exists on the Z or your linux box, or copy the files off, reformat the card, and copy them back on.

Generally when a UNIX filesystem driver finds an error, it sets it to read-only.

The only other thing would be if you moved the switch on the side of the SD.

[mike151]

Hi,

I faced the same kind of problems last week.  After trying several things, I finally did this:

1) rebooted and logged in as root in command line mode
2) unmounted the SD
3) formated it using mkfs.vfat
4) mounted it back
5) rebooted

So far it is still working well. I think the file system in the SD was corrupted.

Hope it helps

Mike

[suruaZ]

Thanks tz and mike151,

Yes it looks like corrupted filesystem. I got a batch of rubbish in one folder on SD.

suruaZ

[rgrep]

Filesystem corruption can be caused by bad blocks on your SD card.  I had a problem with a 256MB SanDisk SD which caused it to always corrupt when I stored a lot on it.  You can do a read-only bad block scan by going to a terminal window, and typing the following as root:

umount /mnt/card
badblocks -sv /dev/mmcda1

When I did this to my SanDisk card I found that only about the first 108 MB were free of bad blocks!  I repartitioned it to only use the first 108 MB and I didn't have any trouble with it after that.

[raychow]

I had that problem after copying MP3s to my 256MB SD.  I found that there was less then 2MB left then it became readonly.    Everything back to normal after cleaned up my SD.

Kudo