Enable Sideloading on the Supernote

• Open Settings on your Supernote and go to Security and Privacy.
• Enable Sideloading by switching the toggle.

Install Google Platform Tools on Your Computer

• Download the SDK Platform Tools.
• Install them on your machine. On Linux, the package includes an application named adb, which is required.

Connect Your Computer and Supernote

• Connect your Supernote to your computer.
• Run the following command to verify the connection

adb devices

Install F-Droid

• F-Droid is an app store for Android devices (including the Supernote).
• Download the fdroid.apk file and scan it with your preferred antivirus tool (e.g., VirusTotal).
• Once verified, upload the APK to your Supernote:

adb install <path>/F-Droid.apk

Install the Aurora Store via F-Droid

• On first launch, F-Droid may take a while to load available apps (requires Wi-Fi).
• Search for Aurora and install the Aurora Store. The Aurora Store is an open-source client for Google Play with a clean design and privacy features.

Install Obsidian from the Aurora Store

Open the Aurora Store and download Obsidian to your Supernote.

Customize Obsidian Settings

• On first launch, create a new vault or sync an existing one.
• For appearance, I recommend installing the Minimal theme under Appearance.
• The theme also has a companion plugin called Minimal Theme Settings.
• Switch the color scheme to E-Ink for an excellent reading and writing experience on the Supernote.

✨ That’s it! You now have Obsidian running on your Supernote, optimized for its e-ink display.

How To Do

Install the zfs-auto-snapshot package

sudo apt install zfs-auto-snapshot

On Ubuntu and Debian, cron scripts are already in place to trigger the script.

Enabling or disabling automatic snapshots for a specific ZFS is done via ZFS properties. This property is inherited by all descendant datasets, so there is no need to set it manually for each one.

sudo zfs set com.sun:auto-snapshot=true zhome/home

You should also specify where you don’t want to see snapshots.

sudo zfs set com.sun:auto-snapshot=false zhome/home/tstusr1
sudo zfs set com.sun:auto-snapshot=false zhome/home/tstusr2

You can enable or disable frequent (every 15 minutes), hourly, daily, weekly or monthly snapshots. They are all enabled by default, so the first snapshot should appear soon.

zfs set com.sun:auto-snapshot:frequent=false zhome/home/tstusr
zfs set com.sun:auto-snapshot:daily=true ...
zfs set com.sun:auto-snapshot:monthly=true ...
...

The following commands are helpful for listing, creating and destroying snapshots:

zfs list -t snapshot

zfs snapshot -r zpool/foo/bar@name

zfs destroy zpool/foo/bar@name

To restore to a certain snapshot, ZFS will roll back all the files and delete all the newer snapshots, so be careful!

zfs rollback zpool/foo/bar@name -r

ZFS itself does not support deleting large numbers of snapshots, but this command comes in handy for that purpose.

sudo zfs list -H -o name -t snapshot zhome/somedir | xargs -n1 zfs destroy

ZFS rollbacks are permanent. They recover everything from the snapshot. If you only want to recover some files or directories, ZFS does not support this directly. However, there is a workaround: Clone the snapshot to a different location and mount the clone. Restore the required files and then delete the clone.

sudo zfs clone zhome/home/ebablick@zfs-auto-snap_frequent-2025-08-25-1845 \
         -o mountpoint=/mnt zhome/ebablick_clone_of_snapshot_2025-08-25-1845

copy /mnt/... /to/...

sudo zfs destroy zhome/ebablick_clone_of_snapshot_2025-08-25-1845 -r

Take a look at the zfs-auto-snapshot(8) manual page. The tool itself offers a few interesting options for executing pre- and post-snapshot commands. The number of snapshots to keep can also be configured via command line arguments, which then need to be adapted for the cron jobs.

Setup Steps

Preparing the Device (Repartitioning)

• The NVMe device name can change during a reboot of a Linux system. For example, what was previously /dev/nvme1n1 could now be /dev/nvme0n1, or vice versa. The lsblk -f command is useful for distinguishing between devices that have already been used and those that have just been added.

• wipefs removes old partitions/signatures for a device

sudo wipefs -a /dev/nvme1n1
/dev/nvme1n1: 8 bytes were erased at offset 0x00000200 (gpt): 45 46 49 20 50 41 52 54
/dev/nvme1n1: 8 bytes were erased at offset 0xe8e0db5e00 (gpt): 45 46 49 20 50 41 52 54
/dev/nvme1n1: 2 bytes were erased at offset 0x000001fe (PMBR): 55 aa
/dev/nvme1n1: calling ioctl to re-read partition table: Success

• Although there are other tools that can manipulate partition tables, I still use fdisk to create a single large partition on the disk. The fdisk suggestions help to create a partition with the correct alignment, which prevents performance issues or error messages in the subsequent steps. The (g) command creates a new GPT. (p) prints the partition table. (n) triggers the creation of a new partition. (t) allows you to specify a partition type, and (w) makes the data persistent by writing the information to the disk.

sudo fdisk /dev/nvme1n1
Command (m for help): g
Created a new GPT disklabel (GUID: AC0EB50D-4E46-46C7-892D-BEE19E49E76F).

Command (m for help): p
Disk /dev/nvme1n1: 931,51 GiB, 1000204886016 bytes, 1953525168 sectors
Disk model: Samsung SSD 990 EVO 1TB                 
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: AC0EB50D-4E46-46C7-892D-BEE19E49E76F

Command (m for help): n
Partition number (1-128, default 1):
Partition number (1-128, default 1): 
First sector (2048-1953525134, default 2048): 
Last sector, +/-sectors or +/-size{K,M,G,T,P} (2048-1953525134, default 1953523711): 
Created a new partition 1 of type 'Linux filesystem' and of size 931,5 GiB.

Command (m for help): p
Disk /dev/nvme1n1: 931,51 GiB, 1000204886016 bytes, 1953525168 sectors
Disk model: Samsung SSD 990 EVO 1TB                 
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: AC0EB50D-4E46-46C7-892D-BEE19E49E76F
Device         Start        End    Sectors   Size Type
/dev/nvme1n1p1  2048 1953523711 1953521664 931,5G Linux filesystem

Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.

Encryption with LUKS/LUKS2

• The new partition should be LUKS-encrypted. Rather than using device names such as /dev/nvme…, I would like to identify the partition by a UUID. To this end, I will generate a new ID with uuidgen to pass to cryptsetup. The passphrase for the encryption must be specified, and lsblk can be used to verify the result.

uuidgen
168b9568-0540-40b8-b939-882be97eb6bb

cryptsetup luksFormat -q --type luks --sector-size 4096 --cipher aes-xts-plain64 --key-size 256 --uuid 168b9568-0540-40b8-b939-882be97eb6bb --pbkdf argon2i /dev/nvme1n1p1

lsblk -f
...

• The partition can now be opened. I chose the /dev/disk/by-uuid/… path for the device, and the device name will also later be available by the name UUID, prefixed by ‘luks-‘, as with the other partitions initially created by the Debian installer. The ls command on /dev/mapper shows that the partition is available after entering the correct passphrase.

sudo cryptsetup luksOpen --persistent --allow-discards --perf-no_write_workqueue --perf-no_read_workqueue /dev/disk/by-uuid/168b9568-0540-40b8-b939-882be97eb6bb luks-168b9568-0540-40b8-b939-882be97eb6bb
Enter passphrase for /dev/disk/by-uuid/168b9568-0540-40b8-b939-882be97eb6bb:

ls -la /dev/mapper/
...
lrwxrwxrwx  1 root root       7 24. Aug 00:56 luks-168b9568-0540-40b8-b939-882be97eb6bb -> ../dm-2

Opening/Mounting the Device

• Once a partition has been encrypted, it must be activated/opened during the boot process so that it can be used. For the root partition and SWAP of a Debian system, this is done early by GRUB, even before the OS is running. For other partitions, such as our new one, systemd will perform this task. This step must be enabled by installing the necessary package.

sudo apt install systemd-cryptsetup

• Systemd also asks for a passphrase during the boot process, but I want a separate key file that systemd can automatically use to open the encrypted device.
• dd creates a key file containing random data. Access permissions for this file are restricted using the chmod command. The key is then added to the list of authorized keys that can access the device, which requires entering the initial passphrase. Finally, the status is dumped so that it can be verified.

sudo dd if=/dev/urandom of=/crypto_keyfile_home.bin bs=512 count=8

sudo chmod 600 /crypto_keyfile_home.bin

sudo cryptsetup luksAddKey /dev/nvme1n1p1 /crypto_keyfile_home.bin

sudo cryptsetup luksDump /dev/nvme1n1p1

• In order for systemd to recognize the new device, the /etc/crypttab file must be updated with a new entry (in one line).

sudo vi /etc/crypttab
...
luks-168b9568-0540-40b8-b939-882be97eb6bb UUID=168b9568-0540-40b8-b939-882be97eb6bb	/crypto_keyfile_home.bin luks,discard,keyscript=/bin/cat

• After rebooting, the ls command should show that all three encrypted devices are ready.

ls -la /dev/mapper/
....
lrwxrwxrwx  1 root root       7 23. Aug 16:29 luks-011bd881-8ec3-4a12-91df-52e1928539fb -> ../dm-1
lrwxrwxrwx  1 root root       7 24. Aug 00:56 luks-168b9568-0540-40b8-b939-882be97eb6bb -> ../dm-2
lrwxrwxrwx  1 root root       7 23. Aug 16:29 luks-45cabb59-0bb5-4737-b6c9-6007657d7a27 -> ../dm-0

• The device can now be formatted and mounted …

Ubuntu 24.04 is working there quite well. Thanks to TUXEDO, the hardware support if great but one thing what made me cringe was the lack of hibernation support and sporadic wake-ups can be frustrating and dangerous if the notebook should sleep in the bag when you are on the go.

The default Ubuntu 24.04 (and also TUXEDO’s adapted TUXEDO OS) does not setup a SWAP partition of the correct size which makes hibernation impossible. Even if you do this setup yourself you will find out that modes like SuspendThenHibernate will cause the system never to hibernate due to the unnecessary wake-up calls.

The frustration with hibernation was the main reason to give Debian 13 Trixie a try to find out if this distributions also has such issues.

Necessary Steps

I can already summarize that not only was the default installation a success, but hibernation also works perfectly. Minor configuration steps were necessary on Debian 13 Trixie.

• The default installation on NVMe was problem-free. Debian supports LUKS encryption of partitions, including the SWAP partition, which contains the complete extract of the working memory in hibernation mode.
• The SWAP partition automatically has the size of the RAM—more precisely, it is even slightly larger so that the contents of the RAM still fit in the partition despite the LUKS header. A manual hibernation test after installation confirmed that hibernation is working.

sudo systemctl hibernate

• After restarting the notebook, the system wakes up again, asks for the encryption password, boots Linux, and continues where it left off.
• The file /etc/systemd/sleep.conf contains the default settings for systemd, which is responsible for suspend and hibernate. I have adjusted the settings slightly to suit my needs:

sudo vi /etc/systemd/sleep.conf

[Sleep]
AllowSuspend=yes
AllowHibernation=yes
AllowSuspendThenHibernate=yes
AllowHybridSleep=yes
#SuspendState=mem standby freeze
#HibernateMode=platform shutdown
#MemorySleepMode=
HibernateDelaySec=30m
HibernateOnACPower=yes
#SuspendEstimationSec=60min

• In particular, the HibernateDelaySec is set to 30m. In combination with my Gnome settings, this means that Gnome dims the screen after 10 minutes. After 15 minutes, the notebook is suspended for 30 minutes. During this time, touching the touch pad or pressing a key is enough to wake it up, but if you don’t do this, the notebook wakes up on its own after the time has elapsed, only to hibernate.
• The Gnome shutdown menu does not yet include the option to trigger ‘hibernate’, ‘suspend then hibernate’, or ‘hybrid sleep’ from the graphical user interface. However, this can be quickly remedied with a Gnome shell extension called Hibernate Status Button.

• If you’re wondering what hybrid means: In this mode, the memory dump is written before the notebook is suspended and is available when a reboot is required, for example, if the battery runs out during sleep mode.
• When you close the lid of a laptop, Debian Trixie automatically puts the laptop into sleep mode. If you would prefer something else to be triggered instead, this can be changed in /etc/systemd/logind.conf.

sudo vi /etc/systemd/logind.conf

HandleLidSwitch=suspend-then-hibernate
HandleLidSwitchExternalPower=suspend-then-hibernate
...