Raspberry Pi Use a Z-Wave Controller USB Key with openHAB in Docker on a RPI 4

It took me quite some hours to be able to use my Aeotec Z-Stick Gen5 (ZW090) key within my Docker image of openHAB, running on a Raspberry Pi 4 (with a Raspberry Pi OS). Here are all the tips I used.

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First, before plugging the controller  in your RPI, configure it to see the Serial Ports. Connect onto your RPI within a SSH Console (ex.: via Putty)  and type the command:

sudo raspi-config

Use "5 interfacing Options" > "P6 Serial" > "Yes" > "Ok"

And now reboot.

Next, back into a SSH conscole, check what USB devices already exists with the command:


Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

And flush the kernel and boot logs:

sudo dmesg -c >> ~/dmesg-`date +%d%m%Y`.log

Then, plug your Z-Wave Controller USB Key in a USB Port and check that it's detected and mounted properly:


Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 009: ID 0658:0200 Sigma Designs, Inc. Aeotec Z-Stick Gen5 (ZW090) - UZB
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub


[ 3124.779069] usb 1-1.4: new full-speed USB device number 9 using xhci_hcd
[ 3124.919928] usb 1-1.4: New USB device found, idVendor=0658, idProduct=0200, bcdDevice= 0.00
[ 3124.919942] usb 1-1.4: New USB device strings: Mfr=0, Product=0, SerialNumber=1
[ 3124.919953] usb 1-1.4: SerialNumber: 32303136-3131-3033-3030-303031383932
[ 3124.926704] cdc_acm 1-1.4:1.0: ttyACM0: USB ACM device


"lsusb" should show you a new device. Ex.: Aeotec Z-Stick Gen5 (ZW090) - UZB.

And "dmesg" must should you the mount point: cdc_acm 1-1.4:1.0: ttyACM0: USB ACM device.

If you don't see the mount point, then you possibly have a device not supported by the RPI 4. It seems that it is the case with the old Aeotec "Z-Stick Gen5". "New Z-Stick Gen5" and "Z-Stick Gen5+" should however be compatible. But there is a trick: plug your key on the RPI 4 via a USB HUB (2.0 or 3.0).

I presume that the Docker Image is already up and running. If not, install it.

sudo useradd -r -s /sbin/nologin openhab
usermod -a -G openhab pi
mkdir /opt/openhab
mkdir /opt/openhab/conf
mkdir /opt/openhab/userdata
mkdir /opt/openhab/addons
chown -R openhab:openhab /opt/openhab

Check the id of the user openhab with:

id openhab

uid=999(openhab) gid=994(openhab) groups=994(openhab)

Grant access on the Serial Port for the user 'openhab':

sudo chmod 777 /dev/ttyACM0
sudo chown openhab /dev/ttyACM0

And use the uid and gid found above in the following command, setting the ttyA* found previously and specifying the version to be used:

docker run --name openhab --net=host --device=/dev/ttyACM0 -v /etc/localtime:/etc/localtime:ro -v /etc/timezone:/etc/timezone:ro -v /opt/openhab/conf:/openhab/conf -v /opt/openhab/userdata:/openhab/userdata -v /opt/openhab/addons:/openhab/addons -d -e USER_ID=<uid> -e GROUP_ID=<gid> --restart=always openhab/openhab:latest


Now, using Portainer (because it's easy), open a console within openhab... Portainer is not yet installed ? Do it with:

docker run -d -p 9000:9000 -p 8000:8000 --name portainer1 --restart always -v /var/run/docker.sock:/var/run/docker.sock -v portainer:/data portainer/portainer:latest

Go to the page http://<Your RPI IP>:9000, open the Containers and click on the "Exec Console" icon of 'openhab' container:

Grant the same accesses inside the image than on the RPI:

sudo chmod 777 /dev/ttyACM0
sudo chown openhab /dev/ttyACM0

chown -R openhab:openhab /opt/openhab

Now restart the 'openhab' container (with the icon Restart ;) ). It will take some minutes to be available. But once you can get into it, go to the Things and configure the Controller to use the Serial Port ttyACM0:


Et voilà

Raspberry Pi Raspberry Pi's SD card full ?

Trying to update one of my Raspberry Pi Desktop, I see messages pretending that there is not enough free space ? 

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I saw that my Pi was full when I tried to update it with

sudo apt-get update && sudo apt-get upgrade -y

 Error writing to output file - write (28: No space left on device)

I could also see that there was no free storage anymore as the system was unable to allocate the swap file:

systemctl status dphys-swapfile.service

dphys-swapfile.service - dphys-swapfile - set up, mount/unmount, and delete a swap file
Loaded: loaded (/lib/systemd/system/dphys-swapfile.service; enabled; vendor preset: enabled)
Active: failed (Result: exit-code) since Sun 2020-06-28 12:35:15 BST; 4min 21s ago
[...]Jun 28 12:35:15 helios dphys-swapfile[327]: want /var/swap=100MByte, restricting to 50% of remaining disk size: 0MBytes
Jun 28 12:35:15 helios systemd[1]: Failed to start dphys-swapfile - set up, mount/unmount, and delete a swap file.

And indeed, the swap file was 0B:

free -h

      total   used   free   shared  buff/cache  available
Mem: 3.8Gi 285Mi 2.7Gi 11Mi    886Mi       3.4Gi
Swap: 0B      0B     0B

Start to investigate with:

sudo df -h

Filesystem      Size  Used Avail Use% Mounted on
/dev/root 29G 29G 0 100% /
devtmpfs 1.8G 0 1.8G 0% /dev
tmpfs 2.0G 0 2.0G 0% /dev/shm

Or use the version for Inode which won't include the mounted drives

sudo df -i

Filesystem Inodes  IUsed  IFree   IUse% Mounted on
/dev/root 1895552 328167 1567385 18% /
devtmpfs 117763 409 117354 1% /dev
tmpfs 183811 1 183810 1% /dev/shm

Check, in the output of those commands, that the size of the root partition (/dev/root) is close the the size of your SD (Here above, I have IUsed =~ 32G). If it is not the case, enlarge it with:

sudo raspi-config

7 Advanced Options > A1 Expand Filesystem 


If the size of the root partition is maximum, then investigate to find the very large stuff with:

sudo du -xh / | grep -P "G\t"

1,2G /opt/openhab/userdata
1,2G /opt/openhab
1,2G /opt
1,3G /usr
11G /var/lib/docker
11G /var/lib
11G /var
16G /mnt/backup
16G /mnt
29G /

To only have the size of the first level folders, use:

sudo du -xh --max-depth=1 / | grep -P "G\t"

1.2G /opt
1.3G /usr
11G /var
16G /mnt
29G /

Check, in the output of that command, if there as any folder or file which could be cleaned-up.

You can also us this to navigate into your SD:

sudo mount --bind /  /mnt
sudo ncdu -x /mnt

-- /mnt ------------------------
15,1 GiB [##########] /mnt
10,6 GiB [###### ] /var
1,3 GiB [ ] /usr
1,2 GiB [ ] /opt
415,3 MiB [ ] /home
353,3 MiB [ ] /lib
9,3 MiB [ ] /bin

You can navigate in this table (with keys up and down) and open folders (press enter) to see the details of their content. Exit this table by pressing "q".

If by any accident, you don't succeed to delete a large file or folder (especially if located under /media or /mnt), check that it's not on a mounted drive. Auto-mount are usually in /etc/fstab and may only be :

cat /etc/fstab

You can umount all at once with

sudo umount -a -t cifs -l


Regarding packages, You can cleanup some space with:

sudo apt-get autoremove

sudo rm -R /var/cache/

sudo mkdir -p /var/cache/apt/archives/partial
sudo touch /var/cache/apt/archives/lock
sudo chmod 640 /var/cache/apt/archives/lock
sudo apt-get clean


If you are using docker,

you can check the space consumed with:

sudo du -sh /var/lib/docker/overlay2

docker system df

you can cleanup some space with:

docker system prune -a -f

docker system prune --all --volumes --force

docker volume rm $(docker volume ls -qf dangling=true)


If using GitLab, you can cleanup some space with:

sudo gitlab-ctl registry-garbage-collect


Other useful commands:

sudo find / -type f -size +500M -exec ls -lh {} \;

sudo touch /forcefsck ; sudo reboot

sudo resize2fs /dev/mmcblk0p2 ; sudo reboot

After reboot check the resize status with:

systemctl status resize2fs_once.service

If you see the error "Failed to start LSB: Resize the root filesystem to fill partition", you can disable the resize2fs with:

sudo systemctl disable resize2fs_once


What was the issue in my own case: my remote folder for backup was not mounted anymore on /mnt/backup but the backup script run and stored a 16Gb file into the local folder /mnt/backup. I have been able to delete the local backup by commenting the related shared folder in /ect/stab, rebooting and then deleting /mnt/backup.

Et voilà!

Raspberry Pi Run Raspberry Pi Desktop 4 in VMWare

Instead of testings new softwares or configs on my actual RPI, I do it in a VM Machine. Much easier to rollback if I do a mistake. There are many videos on YouTube to explain how to install the Raspberry Pi Desktop in VMWare.

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The ISO image of Raspberry Pi Desktop is available here.

I did create an VM, as illustrated here, with:

  • 4GB Memory
  • 32GB Hard Disk(SCSI)
  • USB 3 .1
  • And everything else "by default"
    • 1 processor
    • NAT Network Adapter
    • ...

I did:

  • a "Graphical Install" of the Raspberry Pi Desktop
  • enable SSH
  • keep the password "raspberry" for the user pi (with auto-login enabled)
  • configure the keyboard for me (Belgian - Azerty)
  • configure to location as Brussels/Belgium
  • install the VMWare-Tools (screen resolution maximized automatically)
  • Create an icon "Desktop Update" to update the packages via: sudo apt-get update && sudo apt-get upgrade -y

And here attached in the resulting VM (a 4.5GB zip file). Download it, unzip and double click the file "Raspberry Pi 4.vmx" to open the VM into your VMWare Workstation.

Et voilà.

Raspberry Pi Create a Plex Media Player with a Raspberry 4

I used to run Rasplex on a RPI 2 to play movies from my Plex Media Server. Unfortunately Rasplex has not been updated to run on a RPI 4. Here is how to build PMP for RPI 4.

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Install an OS on your RPI 4

  1. Download the "Raspberry Pi Imager" here.
  2. Download next the "Raspberry Pi OS (32-bit) with desktop" here (the 64-bit is still only in beta. See here). Unzip the file.
    • This is the smallest image (no extra softwares) with a Desktop (mandatory to display the Plex Media Player GUI)
  3. Install and Run the "Raspberry Pi Imager" to setup the "Raspberry Pi OS" on a micro-SD card.
    • Click on "Choose OS"

    • Select "Use Custom"

    • Pick the .img file "YYYY-MM-DD-raspios-buster-armhf.img" unzipped from the "Raspberry Pi OS (32-bit) with desktop" image.
    • Next Click "Choose SD" and "Write".
    • Once the operation completed, install the micro-SD in your RPI 4 and turn it on. The Raspberry Pi Desktop will appear after some automatic reboots. Follow the setup of the Welcome screen. Steps are:
      • Setup the Country (use Page up and Page down in the Country Combo to scroll faster)
      • Change the Password of the user 'pi'. ATTENTION: the keyboard layout is most probably not the right one. Untick the "Hide characters" option to check what you type!
      • Set Up Screen
      • Select Wireless Network (You can skip this step if the RPI is connected via ethernet). Again, untick the "Hide characters" option to check what you type!
      • Update Software
      • Click "Restart" on the last step "Setup Complete"

Configure your OS

Open a "Terminal" :

First, type this command in the Terminal to check your IP address:


Type next this command to configure the os:

sudo raspi-config

Among other:

  • Configure your keyboard if required via "4 Localisation Options" > "change keyboard layout"
    • If your keyboard is not in the list, use the Generic 100x-Key PC corresponding to your layout. Look the picture of this wiki page for more details.
    • You can possibly also find more info about your keyboard here.
  • Enable SSH via "5 Interfacing Options" > "P2 SSH"
  • Give at least 512MB or more to your GPU via "7 Advanced Options" > "Memory Split" (I did set 512. Using 1024 result in a black screen after reboot)
  • I gave the whole micro-SD card storage for the OS via "7 Advanced Options" > A1 Expand File System"
  • I set the audio output on the HDMI port via "7 Advanced Options" > A4 Audio"
  • NB.: I don't use the 4Kp60 HDMI, but it can be configured via "7 Advanced Options" > AA Pi 4 Video Output"
  • Finally, reboot to be sure that it still work.
    • If you have an issue, wait for 3 minutes and proceed with the next step here under.


You can now open a SSH console from your PC (E.g: using PuTTY) to connect on the IP address found previously and login with the user 'pi' and the password you introduced during the installation.

You will possibly get a PuTTY Security Alert because of the ssh key fingerprint... Accept if you are sure that you are connecting safely to your RPI.

If it seems that your RPI didn't reboot properly and you are not able to connect using SSH after a moment, they you probably have to redo to whole setup from scratch and try other configuration options within raspi-config

If it seems that your RPI didn't reboot properly and you are able to connect via SSH, redo the configuration with the command sudo raspi-config (try to reset the "Memory Split" to 64 if you did change it).

If you want to be sure that your OS is up-to-date, with the very latest fixes, type the following commands:

sudo apt-get update
sudo apt-get full-upgrade

And finally disable the screen sleep with the command

sudo sed -i 's/#xserver-command=X.*/xserver-command=X -s 0 dpms/g' /etc/lightdm/lightdm.conf

Build PMP for your RPI 4

Use now the SSH console (to be able to copy/paste from here) to execute this:

sudo apt-get install -y autoconf automake libtool libharfbuzz-dev libfreetype6-dev libfontconfig1-dev libx11-dev libxrandr-dev libvdpau-dev libva-dev mesa-common-dev libegl1-mesa-dev yasm libasound2-dev libpulse-dev libuchardet-dev zlib1g-dev libfribidi-dev git libgnutls28-dev libgl1-mesa-dev libsdl2-dev cmake python3 python python-minimal git mpv libmpv-dev

Then these 3 commands:

wget https://github.com/koendv/qt5-opengl-raspberrypi/releases/download/v5.12.5-1/qt5-opengl-dev_5.12.5_armhf.deb 
sudo apt-get install -y ./qt5-opengl-dev_5.12.5_armhf.deb
rm qt5-opengl-dev_5.12.5_armhf.deb

And finally these:

mkdir ~/pmp
cd ~/pmp
git clone git://github.com/plexinc/plex-media-player
cd plex-media-player/
mkdir build
cd build
cmake -DCMAKE_BUILD_TYPE=Debug -DQTROOT=/usr/lib/qt5.12/ -DCMAKE_INSTALL_PREFIX=/usr/local/ ..
make -j4
sudo make install

Now, PMP can be run. Go back to the Raspberry Pi Desktop, and type this command in a Terminal:

plexmediaplayer --fullscreen --tv &

In my case, the option 'tv' is not convenient (I can't see enough on the screen)...

You will have to Sign In via the link page of Plex.tv and next configure Plex Media Player.

Configure PMP to launch at boot

Back into you SSH Console, on your PC, create a new user 'plex' with a password:

sudo adduser plex
sudo adduser --disabled-password plex
sudo passwd -d plex

Login as 'plex' in your RPI desktop to run once PMP via a Terminal (Without this step, it will not be displayed full screen after an autologin):

plexmediaplayer --fullscreen --tv &

Configure the user 'plex' to autologin with a desktop session named 'plex':

sudo sed -i 's/#*user-session=.*/user-session=plex/g' /etc/lightdm/lightdm.conf
sudo sed -i 's/#*autologin-user=.*/autologin-user=plex/g' /etc/lightdm/lightdm.conf
sudo sed -i 's/#*autologin-user-timeout=.*/autologin-user-timeout=delay/g' /etc/lightdm/lightdm.conf

Create the 'plex' desktop:

sudo nano /usr/share/xsessions/plex.desktop

and paste into it:

[Desktop Entry]Name=Plex
Comment=Plex Media Player

And now reboot ! (It can take 3 long minutes !!):

sudo reboot

If there is a configuration issue with the desktop, edit the config via a SSH console and restart lightDM (the Desktop Manager):

sudo service lightdm restart

Tips: I had no issue with getting Plex Media Player in fullscreen but here are notes in case I would have to resize it:

sudo apt-get install -y xdotool
export DISPLAY=':0.0'
xdotool search --onlyvisible --maxdepth 1 ""
xdotool windowmove {window_id} {posx} {posy} windowsize {window_num} {sizex} {sizey}


This is based on a post of Stueh on Plex forum (see here)


If you did configure Plex Media Player on a PC Screen and move next on TV Screen, it will most probably not fit that screen et the resolution will possibly not be correct. In that case, here is how I proceed:

  • Log on your RPI using any SSH console on your mobile or Tablet (I presume that your PC is not next to your TV). I am using "RaspController" on Android
  • Edit the desktop to force an error. Hence, you will fallback on the default Desktop. Type in you SSL console : sudo nano /usr/shared/xsession/plex.desktop
    • Ex.: modify this line to define an invalid path: Exec=xxx/usr/local/bin/plexmediaplayer
  • Now, restart LightDM
    • Either type this in your SSH console: sudo service lightdm restart
    • Or CTRL-ALT-Backspace on the keyboard of your RPI.
  • You will get an error message because 'xxx/usr/local/bin/plexmediaplayer' does not exist and next get a prompt to login.
  • Login as 'pi' 
  • Now, open the Start menu > Preferences > Raspberry Pi Configuration > Display (or Interfaces). If you don't see the 'Start menu' because it is out of the screen, press the 'Windows' key on your Keyboard.

  • Next, change the resolution to fit the limitation of your TV:
    • 480p = DVD, old TV 720 x 480 pixels, format 16/9.
    • 720p = HD Ready, 1280 x 720 pixels, format 16/9.
    • 1080p = Full HD, 1920 x 1080 pixels, format 16/9.
    • 2160p, UHDTV1, 3840 x 2160 pixels, format 16/9 (a.ka. UHD-4K or 4K).
    • 4320p, UHDTV2, 7680 x 4320 pixels, format 16/9 (a.k.a UHD-8K or 8K).
  • Then, open Plex Media Player (Start Menu > ...) and configure it in TV mode. If it does not fit the TV Screen, reduce the resolution.
  • Finally, log off (or restrat lightDM with CTRL-ALT-BACKSPACE) and login as 'plex' to also run Plex Media Player and be sure it's also well configured.
  • Ho, yes, sure: edit again the plex.desktop to remove the xxx in the path of the EXEC setting and reboot.