USB filesystem not recognised

Q I'm trying to use a memory stick to transfer files between computers. This is a 256MB USB 2.0 device. Initially, I used it to copy files from a Mac to my Linux box. The device was recognised and the files copied, but I was then unable to delete the files from the stick. Only by going back to the Mac was I able to clear the device. I then found that the device wasn't actually recognised on my Linux box, probably because it appeared to be completely unformatted. I then wanted to transfer files from my Windows box, which also found the device to be unformatted, and so I formatted the device and copied some files to it. However, the stick is now inaccessible on the Linux box. Using dmesg, I found it was /dev/sda, but it doesn't recognise the filesystem. I tried using mount -t vfat /mnt/removable as a user and as root, but without any success (there is an fstab entry for /dev/sda to mount to /mnt/removable). Can anyone suggest how I can mount this device, or what filesystem is the most appropriate to use in this situation? Also, how do I format it for this?

A Memory sticks can have some extremely strange partition structures, with some being accessible on sda, some on sda1 and others on sda4. You can verify the partition table on the stick using 'fdisk -l /dev/sda', and mount the appropriate filesystem on your Linux system. In theory, using the stick in different boxes won't change the partition structure, although it's not uncommon for certain systems to install the filesystem onto the main device, sda, rather than into the partition that exists. Using VFAT for the filesystem will make it nice and portable, as well as being accessible on Windows, Linux and Mac systems. You won't have the luxury of being able to use Unix UID/GID permissions, but for a simple removable media such as a USB memory stick, it won't matter.

Follow us on or Twitter

Username:   Password: