Updating the Firmware

How the update process works

This section explains how the upgrade process normally works, for a tablet which is able to connect to the internet.

I've had mine for about a month, and have yet to actually connect it to any wifi network. I was able to figure this out using remarkable-update to "intercept" the process. The details of how I did this will be covered below.

Tablet asks about updates

The tablet sends an HTTPS POST request to a reMarkable server, asking if an update is available. The body of the request is an XML block containing ...

  • The current firmware version.

  • The tablet's serial number (i.e. RM110-xxx-xxxxx), along with another machine-specific value called machineid.

  • A language code. (Mine says "en-US".)

  • Several other pieces of information which, to be honest, I don't know what they're for.

Server responds

The server uses the information in the request to decide which firmware update should be installed next, and replies with an XML block containing ...

  • The URL of the directory containing the firmware image.

  • The filename, size, and hash (a kind of checksum) of the firmware image.

Tablet downloads image

The tablet builds the full URL of the image from the information in the XML response, then does a normal GET request for that URL.

The image files I've seen, including the 3.5.2.1807 image I just downloaded, are on the order of 80 MB.

Tablet processes image

The tablet's storage is partitioned into four partitions, with two of them reserved for copies of the operating system. At any given time, only one of these is marked "active", and contains the OS that the tablet should load when it boots up. Normally this will be the OS which is currently running.

  • The newly downloaded image is processed, and the new OS is written to the non-active partition. (The downloaded image file contains the OS, with other information. The OS needs to be extracted from the image.)

  • The "active" flag is changed to point to the partition where the OS was just written.

  • A black bar is shown at the bottom of the tablet's UI, telling the user to reboot in order to use the updated firmware.

The next time the tablet reboots, it will boot using the newly selected partition, and run the new OS.

Effects of upgrading

In addition to the newer software being available, any files which previously existed outside of the /home/ filesystem will be gone, and will need to be created again. This means ...

The tablet's root password will be changed

If you didn't set up a /home/root/.ssh/authorized_keys file, you will need to go into the "Settings → Help → Copyrights and licenses" screen and get the tablet's new root password, as you've probably done before, and then update wherever you may have saved the password.

The tablet's SSH host keys will be re-generated

If this happens, you may see a message like this, and your client will refuse to connect.

$ ssh root@10.11.99.1
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the ED25519 key sent by the remote host is
SHA256:oxJFqzp4eH4eI2RhqOy8AR6qIOdrhagfxvww1KKH5g0.
Please contact your system administrator.
Add correct host key in /Users/jms1/.ssh/known_hosts to get rid of this message.
Offending ED25519 key in /Users/jms1/.ssh/known_hosts:14
Host key for 10.11.99.1 has changed and you have requested strict checking.
Host key verification failed.

To clear this message, you need to tell your SSH client to "forget" the previously saved host key.

  • For OpenSSH (standard on Linux/macOS systems), the "ssh-keygen -R" command does this.

    $ ssh-keygen -R 10.11.99.1
# Host 10.11.99.1 found: line 14
/Users/jms1/.ssh/known_hosts updated.
Original contents retained as /Users/jms1/.ssh/known_hosts.old

  • PuTTY apparently stores host keys in the registry, under this location:

    HKEY_CURRENT_USER\Software\SimonTatham\PuTTY\SshHostKeys

    The only way to delete already-known host keys is to edit the registry by hand.

    I don't use windows so I can't really be any more detailed than this. You may want to do a web search for "putty forget host keys", but be careful with the results - a lot of pages talk about user keys, used for authentication, rather than host keys. If you see anything that mentions an authorized_keys or .ppk file (I think that's what putty calls the files where it stores user authentication keys?), you're looking at the wrong thing.

  • SecureCRT - it looks like it stores the known hosts in a text file called hostsmap.txt. Find this file, open it in a text editor, remove the line with the old host key, and save it.

    You should be able to find this file in the following locations:

    • windows: in the "Application Data" folder, which is most commonly ...

      C:\Documents and Settings\%user%\Application Data\VanDyke\Known Hosts

    • macOS or Linux: no idea. OpenSSH comes with the operating system for free, so other than a brief experiment on Mac OS/X years ago, I've never used SecureCRT on a non-windows platform.

  • If you're using some other SSH client, you'll need to figure out the mechanics of how to forget previously known host keys.

    ❓ If anybody can point me to documentation about how to do this for other SSH clients, or even point out any commonly used SSH clients for other operating systems, let me know and I'll add links here.

Once you've removed the old host key, the next time you SSH into the tablet you will be asked to "accept" the new host key.

$ ssh root@10.11.99.1
The authenticity of host '10.11.99.1 (10.11.99.1)' can't be established.
ED25519 key fingerprint is SHA256:oxJFqzp4eH4eI2RhqOy8AR6qIOdrhagfxvww1KKH5g0.
This key is not known by any other names.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Warning: Permanently added '10.11.99.1' (ED25519) to the list of known hosts.
ｒｅＭａｒｋａｂｌｅ
╺━┓┏━╸┏━┓┏━┓   ┏━┓╻ ╻┏━╸┏━┓┏━┓
┏━┛┣╸ ┣┳┛┃ ┃   ┗━┓┃ ┃┃╺┓┣━┫┣┳┛
┗━╸┗━╸╹┗╸┗━┛   ┗━┛┗━┛┗━┛╹ ╹╹┗╸
reMarkable: ~/

Customizations will be gone

Things like custom templates, static screens, and other "unofficial" customizations will be gone.

If your customizations were installed using RCU ...

  • For custom splash screens, RCU stores copies of your files under the /home/root/.local/share/davisr/rcu/splash/ directory.

    When RCU connects to the tablet after an upgrade, it will notice that these files are not the same as the ones in /usr/share/remarkable/ directory (where the reMarkable software stores them), and offer to copy them into place for you.

  • For custom templates, RCU stores your files in the /home/root/.local/s hare/remarkable/templates/ directory. The /usr/share/remarkable/templates/ directory (where the reMarkable software's built-in templates are stored) will contain symbolic links to these files.

    When RCU connects to the tablet after an upgrade, it will notice the custom files without their corresponding symlinks, and will offer to "re-link" them for you.

Other methods of customizing the tablet may have their own mechanisms to automatically re-install themselves. If worse comes to worst, you may have to just re-upoad the original files.

If you do this, you will then have to go through every notebook in the tablet and find every page which was using the old template. These pages will now have no visible template, because (1) every time RCU uploads a PNG/SVG template, it assigns a random UUID as the filename within the tablet, and (2) the page's metadata will be pointing to the old UUID. As you find each page, you'll need to update them to use the new template from the on-screen menu.

Automatic updates will be enabled

Every OS upgrade will turn on the "Automatic updates" flag.

This is because the files which control whether the automatic update service is running or not, are contained in the filesystem with the OS itself. The files within the image are set up so the service is enabled.

If you don't want this enabled, you will have to remember to disable it after every OS upgrade. If you don't do this, the tablet may download and install OS updates by itself, and you won't know anything about it until you see the black bar at the bottom of the screen, telling you that an update has been installed, and you need to reboot.

If this happens to you, and you don't want to upgrade, the Undo a firmware update section below explains how to undo it.

Upgrade in Steps

At first glance, it seemed to me that reMarkable was going out of their way to prevent people from being able to download firmware images for the tablets. This led to people reverse-engineering the upgrade process (like me, with the page you're reading right now) and building their own "archives" of past software images, and third party utilities to make your tablet install whatever arbitrary firmware image you might want.

I thought this was reMarkable being a "control freak" about the firmware images, but then somebody on the RCU-Develop mailing list pointed out something that I hadn't realized.

The tablets need to be updated in "steps".

For example, you have to update from A→B and then B→C, you can't "jump over" B and upgrade from A→C directly. Or for a more specific example, my tablet started 3.0.5.56 on it, and even though there's a 3.5.2 out there, reMarkable's upgrade server said I should upgrade to 3.2.3.1595.

ℹ️ After I upgraded from 3.0.5.56 to 3.2.3.1595, the next version it offered me was 3.5.2.1807, so I only had to do a total of two upgrades.

Not a huge inconvenience, plus it gave me two upgrade processes' worth of information to use in figuring out the details of how upgrades work.

I'm not 100% sure why they require that upgrades be done in "steps", however I do have an educated guess (based on being a software developer for 20+ years). My guess is ...

  • The files stored in the tablet have a certain format, which may or may not change from one firmware release to another.

  • Part of the firmware update process involves converting the existing data files to the format used by the new firmware.

    This is why you shouldn't "downgrade" without also doing a factory wipe, because once the data files are converted to a newer format, the older firmware might have problems reading them.

  • The conversion process only knows how to convert from a limited number of "old versions". So in the A-B-C example above, the converter in the "C" firmware may only know how to convert B→C, but not A→C.

Making users upgrade "in steps" means that every user whose files are "version X", arrived there using the same "chain of format upgrades" as everybody else, so there will only be one set of "upgrade code" to have to support.

Getting firmware images without updating

My own tablets don't connect to the internet at large. (They do connect to the wifi network at my house, but my firewall is configured with rules to not forward traffic from the tablets to the outside world. This allows me to SSH into the tablets without a USB cable, and allows my Linux server to automatically back up the tablets whenever they're connected and not sleeping.)

Because of this, I have to use remarkable-update to install firmware updates. However, that still leaves me with the problem of how to get the update images.

The process I use is below.

  • This works with macOS and Linux, and it might work for windows, if the tools are avaliable for it.

  • I'm using the 10.11.99.x IPs which are normally used when the tablet is connected to the computer via USB cable. If you connect to your tablet using wifi, or if you've manually changed the tablet's DHCP server to use a different IP range, you will need to adjust some IP addresses below.

ℹ️ One of the items on my "to-do list" is to write a script which automates this process. This may or may not include installing the new image on a tablet, I'm not sure yet.

⚠️ The reMarkable 1 and reMarkable 2 use different images.

This is because they have different hardware. The rm2 images, for example, don't include support for the three hardware buttons on the rm1.

If you own both models, you will need to do this process once for each model, and you'll need to be careful to install the correct image on each tablet.

Identify your computer's IP address

Before we get into this, there's something that you'll need to understand.

Computers don't have IP addresses.

Computers have interfaces, and INTERFACES have IP addresses.

Every device which talks on a network will have one or more interfaces. The most common examples of this are ethernet ports, wifi connections, and a weird thing called a "localhost" interface which usually has 127.0.0.1 or ::1 as its address, and doesn't connect to anything other than the machine itself.

When you connect a reMarkable tablet via USB cable, the computer thinks it's a USB ethernet interface, and uses DHCP to request an IP address. The tablet runs a DHCP server on the USB cable's "network", which assigns the interface at the computer's end of the cable, an IP address in the same IP range as the tablet. Normally the tablet is 10.11.99.1, and the computer will be assigned an address in the 10.11.99.(2-6) range.

Identify the IP address to which the tablet will need to connect, in order to reach your laptop.

You can see your computer's IP addresses using a command like "ip -4 addr show" or "ifconfig -a". (For windows I think it's "ipconfig /all" maybe?) You're looking for the IP which is in the same network segment with the tablet - if you're connected via USB cable this will be in the 10.11.99.(2-6) range.

This document will assume the IP is 10.11.99.2, adjust below as necessary.

Start a listener

On the computer, start a copy of either netcat (aka nc) or ncat, listening on a port. One or both should be available from your system's software repositories (i.e. yum, dnf, apt, brew, etc.)

For this document I'll use nc (because it comes with macOS) and 8000 as the port number.

$ nc -ln 10.11.99.2 8000 | tee 01-req.txt

At this point, your computer is listening for incoming network connections. Listening on the 10.11.99.x interface means that only other devices on that network segment (i.e. the tablet) will be able to connect - if something on a wifi or other network tries to connect ro port 8000 they won't be able to.

You won't see any output right away, this is fine. When the tablet sends a request to ask for available upgrades, you will see it in this window, and it will be sent to the 01-req.txt file as well.

Configure the tablet

We need to make the tablet talk to our listener when searching for updates.

SSH into the tablet, and edit the /usr/share/remarkable/update.conf file.

# nano /usr/share/remarkable/update.conf

If this is the first time you've done this (since the last OS upgrade), the file will contain something like this:

[General]
#REMARKABLE_RELEASE_APPID={98DA7DF2-4E3E-4744-9DE6-EC931886ABAB}
#SERVER=https://updates.cloud.remarkable.engineering/service/update2
#GROUP=Prod
#PLATFORM=reMarkable2
REMARKABLE_RELEASE_VERSION=3.5.2.1807

Add a SERVER= line at the bottom which points to our listener. If you already had a SERVER= line which was not commented out, either comment out the existing line, or edit that line.

  • Use http:// rather than https://.
  • Use the IP for the computer, and the port number where your listener is ... listening.
  • Copy the rest of the URL from the commented-out SERVER= line.

When you're finished, the file should look something like this:

[General]
#REMARKABLE_RELEASE_APPID={98DA7DF2-4E3E-4744-9DE6-EC931886ABAB}
#SERVER=https://updates.cloud.remarkable.engineering/service/update2
#GROUP=Prod
#PLATFORM=reMarkable2
REMARKABLE_RELEASE_VERSION=3.5.2.1807
SERVER=http://10.11.99.2:8000/service/update2

Save your changes and exit the editor.

  • For nano, type CONTROL-X.
  • For vi, hit ESC then ":wq".

Trigger an update attempt

  • Make sure the "update-engine" service is NOT running.

    This is especially important if you've just edited the config file - if it was already running and you don't stop it, it won't know about your config changes and will try to talk to whatever SERVER= was previously configured in the file.

    systemctl stop update-engine.service

    This is the same as turning off the "automatic updates" switch in the tablet's Settings screen.

  • Wait a few seconds, then start the service.

    systemctl start update-engine.service

    This is the same as turning on the "automatic updates" switch in the tablet's Settings screen.

  • Tell the service to check for updates NOW.

    /usr/bin/update_engine_client -check_for_update

    You won't see anything happening, but behind the scenes the "update-engine" service will be sending a request for available updates to your listener. (The listener won't answer the request, but that's fine - we're not trying to actually do an update right now.)

  • Wait 5-10 seconds, and then stop the "update-engine" service.

    systemctl stop update-engine.service

    When you stop the service, the listener on your computer should also stop by itself.

Examine the request

If you're curious, you can look at the request that the tablet sent to your listener (i.e. that it thought it was sending to reMarkable).

$ cat 01-req.txt
POST /service/update2 HTTP/1.1
Host: 10.11.99.2:8000
Accept: */*
Content-Type: text/xml
Content-Length: 883

<?xml version="1.0" encoding="UTF-8"?>
<request protocol="3.0" version="3.5.2.1807" requestid="{nnnnnnnn-nnnn-nnnn-nnnn-nnnnnnnnnnnn}" sessionid="{nnnnnnnn-nnnn-nnnn-nnnn-nnnnnnnnnnnn}" updaterversion="0.4.2" installsource="ondemandupdate" ismachine="1">
    <os version="codex 3.1.266-2" platform="reMarkable2" sp="3.5.2.1807_armv7l" arch="armv7l"></os>
    <app appid="{98DA7DF2-4E3E-4744-9DE6-EC931886ABAB}" version="3.5.2.1807" track="Prod" ap="Prod" bootid="{nnnnnnnn-nnnn-nnnn-nnnn-nnnnnnnnnnnn}" oem="RM110-nnn-nnnnn" oemversion="3.1.266-2" alephversion="3.5.2.1807" machineid="nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn" lang="en-US" board="" hardware_class="" delta_okay="false" nextversion="0.0.0" brand="" client="" >
        <ping active="1"></ping>
        <updatecheck></updatecheck>
        <event eventtype="3" eventresult="2" previousversion=""></event>
    </app>
</request>

As you can see, there are two "parts" of the file - headers and body, separated by a blank line. The body is an XML message containing information about the tablet making the request, particularly the "current" firmware version. This is because firmware updates need to be done in "steps", as explained above.

Note that I have obscured some values in the example which could be used to identify the tablets I used as an example while writing this page.

Extract the request body

We're going to send this request to reMarkable. In order to do this, we'll need to extract just the body from the request. You can do this by hand, but it's easier to use sed for this.

sed '1,/^\r*$/d' 01-req.txt > 02-req.txt

This sed command is ...

  • START,END d = delete lines from START to END (inclusive)

    • START is "1", meaning the first line of the file

    • END is "/^\r*$/", meaning the first line in the file which is either empty, or contains only "\r" (the "carriage return" character, ASCII 13).

      This is because the request that the tablet sends uses "\r\n" as the line ending. Some versions of sed may recognize this as a line ending, but most will only recognize "\n" (the "newline" or "line feed" character, ASCII 10) as the line ending, so that supposedly blank line may actually contain a "\r" character. The pattern "^\r*$" matches either a line containing just "\r", or a line containing nothing at all.

    So this command will delete lines from the beginning of the file until the empty line (between the headers and the body), and then copy all other lines as-is.

If you're curious, you can inspect the results afterward, and see that it only contains the request body.

$ cat 02-req.txt
<?xml version="1.0" encoding="UTF-8"?>
<request protocol="3.0" version="3.5.2.1807" requestid="{nnnnnnnn-nnnn-nnnn-nnnn-nnnnnnnnnnnn}" sessionid="{nnnnnnnn-nnnn-nnnn-nnnn-nnnnnnnnnnnn}" updaterversion="0.4.2" installsource="ondemandupdate" ismachine="1">
    <os version="codex 3.1.266-2" platform="reMarkable2" sp="3.5.2.1807_armv7l" arch="armv7l"></os>
    <app appid="{98DA7DF2-4E3E-4744-9DE6-EC931886ABAB}" version="3.5.2.1807" track="Prod" ap="Prod" bootid="{nnnnnnnn-nnnn-nnnn-nnnn-nnnnnnnnnnnn}" oem="RM110-nnn-nnnnn" oemversion="3.1.266-2" alephversion="3.5.2.1807" machineid="nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn" lang="en-US" board="" hardware_class="" delta_okay="false" nextversion="0.0.0" brand="" client="" >
        <ping active="1"></ping>
        <updatecheck></updatecheck>
        <event eventtype="3" eventresult="2" previousversion=""></event>
    </app>
</request>

Send the request to reMarkable

This will send a POST request to reMarkable, with the original message body that came from the tablet. As far as reMarkable knows, your tablet is sending the request.

curl -XPOST \
   -H 'Content-Type: text/xml' \
   -H "Content-Length: $( wc -c 02-req.txt | awk '{print $1}' )" \
   --data-binary @02-req.txt \
   https://updates.cloud.remarkable.engineering/service/update2 \
   > 03-response.txt

As you can see, this saves reMarkable's response in an 03-response.txt file.

Get the image URL

Look at the response you received from reMarkable.

$ cat 03-response.txt
<?xml version='1.0' encoding='UTF-8'?>
<response protocol="3.0" server="prod">
  <daystart elapsed_seconds="9791" elapsed_days="6142"/>
  <app appid="{98DA7DF2-4E3E-4744-9DE6-EC931886ABAB}" status="ok">
    <event status="ok"/>
    <updatecheck status="ok">
      <urls>
        <url codebase="https://updates-download.cloud.remarkable.engineering:443/build/reMarkable%20Device/reMarkable2/3.7.0.1930/"/>
      </urls>
      <manifest version="3.7.0.1930">
        <packages>
          <package name="3.7.0.1930_reMarkable2-XSMSQgBATy.signed" required="true" size="79221928" hash="WLN5qHEaHxC24dLF65rGGoz8Ma4="/>
        </packages>
        <actions>
          <action event="postinstall" successsaction="default" sha256="3Jl13KQIJvbdU+Z5AFagEo3Xx227lWAB2tDFbUxAil8=" DisablePayloadBackoff="true"/>
        </actions>
      </manifest>
    </updatecheck>
    <ping status="ok"/>
  </app>
</response>

There are two parts of this which need to be extracted:

  • <url codebase="___" />
  • <package name="___" />

Copy and paste these two values into a single string. The result will look like this:

https://updates-download.cloud.remarkable.engineering:443/build/reMarkable%20Device/reMarkable2/3.7.0.1930/3.7.0.1930_reMarkable2-XSMSQgBATy.signed

This is the URL of the actual image file.

Download the image

Fairly self-explanatory.

Note: the option in this command is an "uppercase letter O", not a "digit zero".

$ curl -LOv https://updates-download.cloud.remarkable.engineering:443/build/reMarkable%20Device/reMarkable2/3.7.0.1930/3.7.0.1930_reMarkable2-XSMSQgBATy.signed

This file can then be installed on a reMarkable tablet using RCU or remarkable-update.

Undo a firmware update

If you suddenly see the black bar at the bottom of the screen telling you that an OS upgrade has been installed, and you don't want to start using that new OS, you may be able to "undo the damage". The upgrade process changes a "firmware variable" that tells the bootloader which partition to load the OS from. You can change the same variable, to control which partition YOU want it to boot into.

  • If you have rebooted since the OS was upgraded, you will already be running the new version. Changing the flags and rebooting will make it boot into the previous OS.

  • If you have not rebooted, the OS upgrade swaps the variables at the end of the process. If you swap them back, the tablet won't boot into the new OS.

Either way, you should check the system to be sure which version is on each partition before changing anything.

ℹ️ Remember that the tablet stores OS images in partition numbers 2 and 3.

Figure out the state of the tablet

  • Figure out which partition your current OS is currently running from.

    # rootdev
/dev/mmcblk2p2

    In this example, the device name ends with p2, so the running OS is stored in partition #2. For rM1 and rM2 tablets, this will either be 2 or 3.

    The OS upgrade process installs the new OS in whichever partition is NOT the currently running system. In this example, the tablet is running from partition 2, so if a new OS was installed, it will be in partition 3. And if a new OS was not installed, partition 3 will contain the previous OS.

  • Figure out which partition the tablet is set to boot from.

    # fw_printenv active_partition
active_partition=3

    The next time the tablet boots, it will load the OS from this partition.

In this example, the tablet is running from partition 2, and set to boot from partition 3. This usually means that an OS update was installed, and the tablet is waiting for the user to reboot.

Verify which versions are on each partition

You can manually check which version is installed in each partition.

For the running partition, check the file which configures the software update service.

# grep VERSION /usr/share/remarkable/update.conf
REMARKABLE_RELEASE_VERSION=3.8.2.1965

For the other partition, mount that partition read-only (so we can't accidentally change anything there) and read the same file from within that partition. In this example, the tablet is running from partition 2, so we're going to mount partition 3.

# mount -o ro /dev/mmcblk2p3 /mnt
# grep VERSION /mnt/usr/share/remarkable/update.conf
REMARKABLE_RELEASE_VERSION=3.9.3.1986

In this example, the tablet is running 3.8.2, and if we reboot it, it will boot into 3.9.3.

Before we forget, un-mount the other partition.

# umount /mnt

Change which partition the tablet boots from

If you need to change which partition the tablet boots from, you'll need to change a few "firmware variables". These are ...

  • active_partition is the partition the tablet will boot from.

  • fallback_partition is the partition it will boot from if it can't boot from the active partition. I believe it will try the active partition three times before "falling back". This should be set to the "non-active" partition.

  • bootcount is a counter used to monitor how many times the tablet has tried to boot from the active partition. This is incremented each time the bootloader tries to boot Linux from a partition, and if this counter reaches 3(?), it will boot from the fallback partition instead. When the tablet boots successfully, this variable will be set back to 0.

  • upgrade_available ... unsure, but every script I've seen that involves the OS upgrade process, sets the value to 0. Not sure what effect setting it to another value would have.

For this example, we want the tablet to boot from partition 2, so it doesn't boot into the OS which was just installed without your knowledge.

# fw_setenv active_partition 2
# fw_setenv fallback_partition 3
# fw_setenv bootcount 0
# fw_setenv upgrade_available 0

While we're looking at this stuff, let's also make sure the auto-update flag is turned off.

# systemctl disable --now update-engine.service

Note that thhis command does exactly the same thing as turning the "Automatic updates" switch off in the Settings → General → Software screen.

ℹ️ If you ever want to enable the service, use this command instead:

systemctl enable --now update-engine.service

Reboot

If you changed anything, or if you just want to reboot the tablet, this command will do it.

# systemctl reboot

This will disconnect your SSH session, and a few seconds later you'll see the tablet rebooting.

Generated 2024-02-19 13:39:29 +0000
initial-75-gbe216ab 2024-02-19 13:38:10 +0000