1 Topic by garvels

  • garvels
  • New member
  • Offline
  • Registered: 2020-12-19
  • Posts: 3

Topic: cannot shrink 3TB fat32 drive

Hello, I have a 3TB USB drive with a FAT32 filesystem.
I want to shrink it to 2TB, but gparted fails when the action is applied.
I'm using the latest gparted live usb. Older versions also fail.
It does say to create  a bug report. I'll try to paste the details from the HTML output:



<tr><th>Device:</th><td>/dev/sdc</td></tr>
<tr><th>Model:</th><td>Intenso External USB 3.0</td></tr>
<tr><th>Serial:</th><td>17EUZ8GAS</td></tr>
<tr><th>Sector size:</th><td>4096</td></tr>
<tr><th>Total sectors:</th><td>732566646</td></tr>
<tr><td colspan='2'>&nbsp;</td></tr>
<tr><th>Heads:</th><td>255</td></tr>
<tr><th>Sectors/track:</th><td>9</td></tr>
<tr><th>Cylinders:</th><td>319201</td></tr>
<tr><td colspan='2'>&nbsp;</td></tr>
<tr><th>Partition table:</th><td>msdos</td></tr>
<tr><td colspan='2'>&nbsp;</td></tr>
</table>
<table>
<tr><th>Partition</th><th>Type</th><th class='number_col'>Start</th><th class='number_col'>End</th><th>Flags</th><th>Partition Name</th><th>File System</th><th>Label</th><th>Mount Point</th></tr>
<tr><td>/dev/sdc1</td><td>Primary</td><td class='number_col'>256</td><td class='number_col'>732563999</td><td>lba</td><td></td><td>fat32</td><td>INTENSO</td><td></td></tr>
</table>
<p>========================================</p>

<table>
<tr><th>Partition</th><th>Type</th><th class='number_col'>Start</th><th class='number_col'>End</th><th>Flags</th><th>Partition Name</th><th>File System</th><th>Label</th><th>Mount Point</th></tr>
<tr><td>/dev/sdd</td><td>Unpartitioned</td><td class='number_col'>0</td><td class='number_col'>15642623</td><td></td><td></td><td>iso9660</td><td>GParted-live</td><td></td></tr>

<b>Shrink /dev/sdc1 from 2.73 TiB to 2.00 TiB</b>&nbsp;&nbsp;00:00:33&nbsp;&nbsp;&nbsp;&nbsp;( ERROR )

calibrate /dev/sdc1&nbsp;&nbsp;00:00:00&nbsp;&nbsp;&nbsp;&nbsp;( SUCCESS )

<i>path: /dev/sdc1 (partition)<br />start: 256<br />end: 732563999<br />size: 732563744 (2.73 TiB)</i>

check file system on /dev/sdc1 for errors and (if possible) fix them&nbsp;&nbsp;00:00:00&nbsp;&nbsp;&nbsp;&nbsp;( SUCCESS )

<b><i>fsck.fat -a -w -v &apos;/dev/sdc1&apos;</i></b>&nbsp;&nbsp;00:00:00&nbsp;&nbsp;&nbsp;&nbsp;( SUCCESS )

<i>fsck.fat 4.1 (2017-01-24)<br />Checking we can access the last sector of the filesystem<br /></i>

<i>Filesystem has 11445958 clusters but only space for 11445246 FAT entries.<br /></i>

shrink file system&nbsp;&nbsp;00:00:33&nbsp;&nbsp;&nbsp;&nbsp;( ERROR )

using libparted

libparted messages&nbsp;&nbsp;&nbsp;&nbsp;( ERROR )


<i>The file system is bigger than its volume!</i>

<i>The information sector has the wrong signature (0).  Select cancel for now, and send in a bug report.  If you&apos;re desperate, it&apos;s probably safe to ignore.</i>

and then it exits if you hit Ignore.

regards,
Marnix

2 Reply by garvels

  • garvels
  • New member
  • Offline
  • Registered: 2020-12-19
  • Posts: 3

Re: cannot shrink 3TB fat32 drive

To answer my own problem: it was solved by using Windows and a free Windows partitioning tool, which gave no errors and did the job.
Of course, I would have preferred to have used Gparted.

regards,
Marnix.

3 Reply by class413

  • class413
  • Moderator
  • Offline
  • Registered: 2007-05-25
  • Posts: 2,376

Re: cannot shrink 3TB fat32 drive

It is strange, because the limit of the volume size for a FAT32 filesystem is normally about 2TB (2047GB) for 512-byte sectors. It can go further with bigger sectors, however the logical sector size is mostly 512 bytes. It seems that this format uses 4096 byte sectors.

*** It is highly recommended to backup any important files before doing resize/move operations. ***

4 Reply by garvels

  • garvels
  • New member
  • Offline
  • Registered: 2020-12-19
  • Posts: 3

Re: cannot shrink 3TB fat32 drive

The first warning I got was from fsck.vfat and indeed mentions the cluster number being unexpected; that I can understand
and relate to the 4K cluster size being unusual, and likely a bug in fsck.
The second warning is from gparted and mentions that 'The information sector has the wrong signature (0).  Select cancel for now, and send in a bug report.  If you're desperate, it's probably safe to ignore'.
My main problem was that 'ignoring' this warning was not possible, it immediately exits the program.
When this could be fixed, others in the future could still use gparted for a similar hard drive resizing problem.

regards,
Marnix.