Moving /boot to a usb key

Question

How do I move the existing /boot partion of a 14.04 root encrypted installation to a usb key?

Answer 1

Test this:

In a normal session:

Insert the usb stick.

Open a terminal. CtrlAltT.

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.