4w ago

Is there a way to move the os to another disk but not /home?

Some years ago, I make the mistake of doing a single partition for the system (I'm using EndeavourOS). Now I have a new disk, and I want to move the OS there, but not /home, which I want to stay in the old drive. How can I do it?

10 comments

Moving the OS is difficult because you would need to reinstall the bootloader which may or may not be easy depending on your skills.
keeping the OS and moving your home is much much easier. as simple as opening fstab and adding a new line entry
- Even if I move the bootloader partition?
  
  depends on if you copy over the partition table as well iirc. For this to work you'll have to have the /etc/fstab file be defined using UUIDs, not disk names. you can do this with something like:
  dd if=/dev/mycurrentdrive of=/dev/newdrive bs=10M
  reinstalling the bootloader isn't hard though, just make sure you know if your system is configured to boot via bios or uefi
  
  There is a few bytes at the beginning of the hard disk that tells the BIOS from where to load the OS.
  These bytes don't belong to any particular partition.
  What you want is very doable you just need to reinstall the bootloader after or else your system won't boot.
  Try to find a Linux person near you to help or if you want to test for your self. Make a simulation using a virtual machine and see if you could accomplish what you want there before doing it in your real system
(First make and test backups, then) Clone the drive. Then point the OS on the new drive to /home on your old drive. Keep or remove old OS files.
Rsync -rav --exclude home / /destination
Depending on how much customization you have done, it might be easier and safer to just install the OS from scratch to the new disk. You'll also end up in a much more "clean" state afterwards.
Your program settings, browser favorites, etc should all be stored in /home/
<user>
Your system settings are generally stored in /etc
I would take a backup of the whole system (important!), then take a second copy of only these two folders (save all the permissions and ownership info, and also use sudo to access all the files in /etc !). After you have saved everything, wipe both disks, set them up like you want and reinstall all the software you need. Finally you can restore from these two folders.
You will not want to restore everything in /etc, just the files you have manually/indirectly edited, and also you will need to preserve the correct file permissions, so be careful on what you do there. Some files like /etc/fstab hold the information on how your disks are mounted, so you really don't want to restore those (same for /etc/passwd, systemd units, and many others). Basically restore selectively only what you need, or reconfigure the software again and just restore your /home
It shouldn't take as much time as it sounds, because most of the settings should be in your home folder, and you can reinstall all the software pretty quickly when you need them. You also won't have to fight all the problems if you end up with a weird/incomplete setup when moving the root.

10 comments