Test this:

In a normal session:

Insert the usb stick.

Open a terminal. Ctrl Alt T .

Identify the usb-stick, suppose is /dev/sdc1, umount it:

sudo -i fdisk -l umount /dev/sdc1

Load gparted

gparted

Delete a patition, create an ext4 partition, apply the changes and close gparted

You must mount the new /boot partition, suppose is new ext4 /dev/sdc1 on a temporary directory, suppose is /media/newboot to copy files to it the original /boot.

Run it:

You create the temporary directory

mkdir /media/newboot

Umount and mount partition

umount /dev/sdc1 mount /dev/sdc1 /media/newboot

To copy files:

cd /boot cp -ax . /media/newboot

This last line is the only one used to clone, attention "." the end.

Now mount the new /boot previous rename the /boot partition.

cd / mv /boot /boot.old mkdir /boot umount /dev/sdc1 mount /dev/sdc1 /boot

Now you have to find the UUID of the partition and edit the /etc/fstab file to mount the partition at startup.

blkid /dev/sdc1 nano /etc/fstab

And you add these lines at the end with that reported blkid UUID.

# /dev/sdc1 was /boot UUID=c676ae51-cb6f-4c0e-b4a9-76850aafa1d6 /boot ext4 errors=remount-ro 0 1

Ctrl + O , save file. Ctrl + X , close nano.

update-grub

Restarting have everything working exactly the same, but with other partitions.

Once everything is working well, delete the /boot.old and /media/newboot

sudo -i rm /boot.old rm /media/newboot

Note:You should be aware that without the usb-stick the system will be unusable.