Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

I have a 320GB USB drive with a single large FAT32 partition. The volume mounts perfectly fine on my Mac OS X 10.5.8 machine and Disk Utility on the mac reports no issues with the volume. I can read/write all data on the drive.

However when I connect the drive to my Ubuntu 9.10 Karmic system, the partition does not mount. dmesg|tail says:

[ 2752.334822] scsi3 : SCSI emulation for USB Mass Storage devices
[ 2752.335040] usb-storage: device found at 3
[ 2752.335044] usb-storage: waiting for device to settle before scanning
[ 2757.330301] usb-storage: device scan complete
[ 2757.331005] scsi 3:0:0:0: Direct-Access     WD       3200AAK External 1.65 PQ: 0 ANSI: 0
[ 2757.331772] sd 3:0:0:0: Attached scsi generic sg2 type 0
[ 2757.355647] sd 3:0:0:0: [sdb] 625142448 512-byte logical blocks: (320 GB/298 GiB)
[ 2757.360737] sd 3:0:0:0: [sdb] Write Protect is off
[ 2757.360749] sd 3:0:0:0: [sdb] Mode Sense: 00 00 00 00
[ 2757.360755] sd 3:0:0:0: [sdb] Assuming drive cache: write through
[ 2757.367618] sd 3:0:0:0: [sdb] Assuming drive cache: write through
[ 2757.367631]  sdb: sdb1
[ 2762.797622] sd 3:0:0:0: [sdb] Assuming drive cache: write through
[ 2762.797636] sd 3:0:0:0: [sdb] Attached SCSI disk
[ 2822.866228] FAT: bogus number of reserved sectors
[ 2822.866237] VFS: Can't find a valid FAT filesystem on dev sdb1.

When I run fsck.vfat -a /dev/sdb1 I get:

root@cartman:~# fsck.vfat -a /dev/sdb1
dosfsck 3.0.3, 18 May 2009, FAT32, LFN
Logical sector size is zero.

Googling "vfat Logical sector size is zero" produced no consensus as to the solution. I would prefer not to have to completely reformat the disk if possible because it contains about 280GB of data I would rather not have to find a temporary home for. Any suggestions?

share|improve this question
add comment

3 Answers

First, I would try to get access to chkdsk.exe if possible and run that on the drive just incase there is a problem with the filesystem and linux is just being much more picky about it.

It seems that fat32 has a backup boot sector at sector 6. You could always try to replace sector 0 with that sector and see if it helps you out, but I would probably try the chkdsk route and see if that helps you out at all.

share|improve this answer
add comment
up vote 1 down vote accepted

This has happened a few more times... it seems to be a problem specific to drives formatted as FAT-32 under Mac OS X 10.5. I backed the drives up on my mac and reformatted the drives on lnux using mkfs.vfat and they were then usable. Not an answer to my question, but I wanted to close this, so I'm just posting what I did. (If anyone has any other ideas, answer this question and I'll try them, and accept your answer if it works!)

share|improve this answer
add comment

Have you tried checking the nls modules?

A good resource is http://www.nslu2-linux.org/wiki/HowTo/MountFATFileSystems.

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.