Looking for guidance on planned config with BTRFS, Hibernation, Encryption, root and home

[flussotter]

Hey everyone,

Today, I got a new Dell Pro 14 Plus PB14250 laptop from my employer. It is certified for Ubuntu 24.04 LTS.
I'm still new to Linux and don't want to mess up the configuration. So I thought it would be better to ask here for advice on what to do first, as I'm having trouble knowing which online resources to use because there are so many of them.

I'm a software dev apprentice, so I use the laptop mainly for coding, virtualization, and regularly install apps.

Here are the device's specifications:

CPU: i7 Ultra
RAM: 32 GB
SSD: 512 GB
I also have a Dell docking station for it, but I can't remember the model at the moment.
(I heard that I might have to install some additions to the Kernel)

Here's how I would like to set it up:

- BTRFS file system for rolling back if something goes wrong
- A separate root and home partition, for easy reinstall or upgrade of Kubuntu
- Hibernation for a faster startup
- Full disk encryption
- drive sizes:
- boot 1 GB
- root 60 GB
- swap 32 GB
- home remaining 419 GB

My Questions:

- Should I create a swap partition or a swap file in my configuration, what is the recommendation here?
- Can each partition be formatted in BTRFS?
- Are the planned partition sizes sufficient?
- Can I have only 1 password prompt to unlock all partitions in one go?
- I can encrypt the drive from within UEFI, so will I even need full disc encryption from Kubuntu?
- What will I have to install about the Kernel to make it work with the docking station?
- Is there anything else I should know about, or take care of? Do I need to configure it in a special way?
- Are there any beginner-friendly guides for what I'm planning to do? I'm tech-savvy, but as I said, I'm pretty new to Linux.

Thank you for reading and your help, I really appreciate it
flussotter

[jlittle]

- BTRFS file system for rolling back if something goes wrong
- A separate root and home partition

These two don't go together, or shouldn't. With btrfs root and home are (by default) separate subvolumes, providing the separation required. With separate partitions, you have to choose sizes, a nuisance if the choices don't work out.

- Should I create a swap partition or a swap file in my configuration, what is the recommendation here?

For hibernation, a swap partition is needed. Presently the installer always creates a swapfile too.

IMO hibernation is overrated, ordinary sleep does the job without fuss, and hibernation is only useful if an extended period, several days say, away from power is anticipated. It was invented when hard drives made cold booting slow.

- Can each partition be formatted in BTRFS?
- Are the planned partition sizes sufficient?

An ESP, a swap partition (sized to just over the size of RAM), and one big btrfs partition with the rest of the space.

- What will I have to install about the Kernel to make it work with the docking station?

I'd expect nothing. The last "docking stations", little boxes on a cable, I used on a Lenovo just plugged in to a USB C and worked, though they could run a bit hot.

[flussotter]

Hi jlittle, thank you for your valuable reply

These two don't go together, or shouldn't. With btrfs root and home are (by default) separate subvolumes, providing the separation required. With separate partitions, you have to choose sizes, a nuisance if the choices don't work out.

Taking a look into gparted on my current laptop, I see root and home being on the same volume, or subvolume like you said. How can I safely remove Kubuntu 24.04 and install 25.04, or maybe even something else like ZorinOS, without loosing my personal files and configs, and while keeping everything fully encrypted?

I'd expect nothing. The last "docking stations", little boxes on a cable, I used on a Lenovo just plugged in to a USB C and worked, though they could run a bit hot.

I thought so too, but on my current Kubuntu 24.04.3 I can't wake the laptop from sleep using the keyboard/mouse. I have to open the lid, and login using the laptop's keyboard, and after this the external screens only turn on when I unplug and power cycle the docking station.

[jlittle]

How can I safely remove Kubuntu 24.04 and install 25.04, or maybe even something else like ZorinOS, without loosing my personal files and configs, and while keeping everything fully encrypted?

I have no experience with encryption, I can't advise with that.

Otherwise, minimally, you could snapshot your @home, say to @homek, install ZorinOS, delete @home then snapshot @homek back to @home. (A send/receive backup of @homek somewhere would be good.) Or just let ZorinOS use the @home as it finds it.

But, I wouldn't do that. I'd modify the Kubuntu install to be using, say, @k, @homek and @swapk, and install ZorinOS alongside kubuntu, in the same fs. When my desktop had only a 200 GB SSD at one point I had seven different installs, not all *bunutus, living in the same btrfs happily (so long as I stopped them fighting over control of the boot). All one has to do is fix up /etc/fstab and grub. If you're the type of user that wants to try out various installs, then you're the type that can use grub and /etc/fstab to have several installs going. For example, soon I'll be upgrading to 25.10, but I'll keep 25.04 bootable for a while alongside 25.10, as well as maybe a fresh install of 25.10. With these multiple OS approaches one is at the mercy of the installers, that think they know better, but Linux itself just needs to be told where the root subvolume is, and then any other subvolumes via /etc/fstab.

[flussotter]

I have no experience with encryption, I can't advise with that.

Otherwise, minimally, you could snapshot your @home, say to @homek, install ZorinOS, delete @home then snapshot @homek back to @home. (A send/receive backup of @homek somewhere would be good.) Or just let ZorinOS use the @home as it finds it.

But, I wouldn't do that. I'd modify the Kubuntu install to be using, say, @k, @homek and @swapk, and install ZorinOS alongside kubuntu, in the same fs. When my desktop had only a 200 GB SSD at one point I had seven different installs, not all *bunutus, living in the same btrfs happily (so long as I stopped them fighting over control of the boot). All one has to do is fix up /etc/fstab and grub. If you're the type of user that wants to try out various installs, then you're the type that can use grub and /etc/fstab to have several installs going. For example, soon I'll be upgrading to 25.10, but I'll keep 25.04 bootable for a while alongside 25.10, as well as maybe a fresh install of 25.10. With these multiple OS approaches one is at the mercy of the installers, that think they know better, but Linux itself just needs to be told where the root subvolume is, and then any other subvolumes via /etc/fstab.

I might be that kind of person one day, but for now, it's way too much risk for something going wrong and bugging me maybe for weeks before I can find a fix. Thus, I will just be a regular user in the meantime.

Speaking of which, thanks to your input I decided to ditch hibernation and separated partitions, as I currently need to focus on making things just work.

Again, thank you so much for your time and effort on helping me out and finding my way!