Completely new to Linux, decided to install Xubuntu onto a usb using the universal usb installer. I have a 64gb usb stick. I set everything up, booted into live - persistent and everything seemed alright until I decided to install some basic programs. I quickly realized that 4gb persistent file would not be enough. I decided to try and resize my partitions and the only one I can see is my fat32 partition I cannot unmount it because 'the CD ROM is busy'. How do I increase the size of my Casper -rw file (File or partition because I can't see it in gparted or fdisk -l?) Or is there any way to create a persistent partition and resize my current one? Any help would be appreciated. Thanks in advance


It looks like it is not possible to make a casper-rw file greater than 4GB because of a limitation of FAT32, however, it is not difficult to make a casper-rw partition.

Note: You may want to backup your data before you start doing this, data can always be lost while partitioning, copying, etc.

This is outlined in Method 0 of https://wiki.ubuntu.com/LiveUsbPendrivePersistent

You'll have to make use another live USB in order to resize the partition. After you've booted into the other live USB,

  1. Open gparted
  2. Resize the FAT32 partition of the original USB drive to almost as small as it can be
  3. Make a new ext4 partition named "casper-rw" (without the quotes)
  4. Click "apply"

Now you just have to copy the data over

sudo dd if=/path/to/casper-rw of=/dev/sdX

Where sdX is the new partition you created (also add "status=progress" if you're impatient and want to see the progress like me)

After it's done copying, delete the original casper-rw file and it should be good to go.

| improve this answer | |
  • Could I use a live CD instead of a second live usb? (Thanks for the answer!) – Joe Sullivan Nov 13 '16 at 22:50
  • Yes, a live CD should do as well – Evan Chen Nov 13 '16 at 22:51
  • any particular reason to use dd instead of cp? – jiggunjer Dec 30 '16 at 9:36
  • cp is to copy files, dd will copy binary data of the partition, and that may matter. the format of casper-rw is difftent than ext4 it's just ext4 is a container for casper-rw file – Pawel Cioch Mar 27 '19 at 3:55

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