Gentoo USB serial passthrough KVM

I have a Conbee II Zigbee receiver. After a restart the USB passthrought stopped working (on the guest VM I always get errors like:

usb 2-2: new low-speed USB device number 25 using uhci_hcd
usb 2-2: Invalid ep0 maxpacket: 64 usb
usb2-port2: unable to enumerate USB device

So I decided, passthrough the USB serial. It’s a little tricky 🙂

    <serial type='dev'>
      <source path='/dev/ttyACM0'/>
      <target type='isa-serial' port='1'>
        <model name='isa-serial'/>

The trick is the serial type because it is dev.


ConBee 2 firmware upgrade on Ubuntu


Installed Deconz software. Downloadable, here:

Download the lates firmware from here:;O=D

Stop all services:

$ sudo systemctl stop deconz && sudo systemctl stop deconz-gui

Stop ModemManager if it is installed:

$ sudo systemctl stop ModemManager

Update the firmware:

sudo GCFFlasher_internal -t 60 -d /dev/ttyACM0 -f <LOCATION_OF_THE FIRMWARE_IMG>/deCONZ_ConBeeII_0x1234567.bin.GCF


Unuable Remmina with squares as characters

I use Ubuntu 20.04 and sometime remmina makes me a joke….

If you start remmina, and you see like this:

remmina uses squares like on that pics

Try this:

rm -rf ~/.cache/fontconfig && sudo fc-cache -r -v

Acutally, it resolves me the problem.

Hassio with supervisor on Gentoo by docker

Supervisor, first start

Docker pull:

docker pull homeassistant/qemux86-64-homeassistant:landingpage

Than, start it:

docker run -d --name hassio_supervisor \
--privileged \
--security-opt apparmor:unconfined \
--security-opt seccomp=unconfined \
-v /run/docker.sock:/run/docker.sock \
-v /run/dbus:/run/dbus \
-v "/opt/hassio/data":/data \
-e SUPERVISOR_SHARE="/opt/hassio/data" \
-e SUPERVISOR_NAME=hassio_supervisor \
-e HOMEASSISTANT_REPOSITORY="homeassistant/qemux86-64-homeassistant" \

Linux Desktop experiences


A long-long years ago (til 2007) I used linux as desktop (Gentoo exactly).

After, the windows 7 and the 10 also will be a very-very good PC OSs.

BUT I tried the Ubuntu 20.04, and it seems work wine from 1 month at my 2in1 PC with WWAN card (DELL 7390).

I would like to collect some useful programs which I found very userful, fast and maintined (actually).

Program typeLinux programWindows alternative
(what I liked to use)
Screenshot maker and editorFlameshotGreenshot
Clipboard managerCopyQDitto
File managerDouble CommanderTotal Commander
SSH session managerRemminaKitty
VNC session managerRemminaUltraVNC
RDP session managerRemminaRDCman (discontinued)

mdadm raid 5 all disk became spare

After an irregular restart, the raid 5 array became unreachable. D’oh!

# cat /proc/mdstat

$ cat /proc/mdstat 
Personalities : [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] 
md3 : inactive sdd3[3](S) sde3[4](S) sdf3[6](S) sdg3[5](S)
      6546850144 blocks super 1.2

As you can see all sd[cdefg]2 partitions are (S)pare.

First, we had to stop the array:

# mdadm --stop /dev/md3

and after we have to reassamle the array:

# mdadm --assemble /dev/md3 /dev/sdc3 /dev/sdd3 /dev/sde3 /dev/sdf3 /dev/sdg3 --verbose

After, we have to see like this:

$ mdadm --assemble /dev/md3 /dev/sdc3 /dev/sdd3 /dev/sde3 /dev/sdf3 /dev/sdg3 --verbose
mdadm: looking for devices for /dev/md3
mdadm: Fail create md3 when using /sys/module/md_mod/parameters/new_array
mdadm: /dev/sdc3 is identified as a member of /dev/md3, slot 0.
mdadm: /dev/sdd3 is identified as a member of /dev/md3, slot 2.
mdadm: /dev/sde3 is identified as a member of /dev/md3, slot 3.
mdadm: /dev/sdf3 is identified as a member of /dev/md3, slot -1.
mdadm: /dev/sdg3 is identified as a member of /dev/md3, slot 1.
mdadm: added /dev/sdg3 to /dev/md3 as 1
mdadm: added /dev/sdd3 to /dev/md3 as 2
mdadm: added /dev/sde3 to /dev/md3 as 3
mdadm: added /dev/sdf3 to /dev/md3 as -1
mdadm: added /dev/sdc3 to /dev/md3 as 0
mdadm: /dev/md3 has been started with 4 drives and 1 spare.

cool part of it:

mdadm: /dev/md3 has been started with 4 drives and 1 spare.

let’s check the result:

$ cat /proc/mdstat 
Personalities : [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] 
md3 : active raid5 sdc3[0] sdf3[6](S) sde3[4] sdd3[3] sdg3[5]
      4910137344 blocks super 1.2 level 5, 512k chunk, algorithm 2 [4/4] [UUUU]
      bitmap: 0/13 pages [0KB], 65536KB chunk

And it done, huh 🙂

Move “Show Applications” right to left of the Dock in Ubuntu

When I installed new Ubuntu 18.04, first thing I have my mind is to move the Dock at botton. I was very happy to see that Ubuntu 18.04 is already provided that option, to enable this you need to go to setting > Dock and then “Position of screen” to bottom.

Yessss, it works.

Image for post

After this one more thing I noticed is “Show applications” is showing at the right side of the Dock but I like it on the left (Event in old versions and mac/ windows its in left). I tried to search in google but nothing found so I thought of writing a notes about it. And finally, I got it working so I thought it will be good to share it with everyone.

Here is the command you need to run for this

gsettings set show-apps-at-top true

Yayyy, its working.

1*AbDjQvjx30Du4QBoNrHegg.png (700×31)

And of course, to back set it false:

gsettings set show-apps-at-top false


Win 10 set default editor

1. Start the registry editor (regedit.exe) and select HKEY_CLASSES_ROOT.

2. Press Ctrl + F to open the Find dialog.


3. Type systemfileassociations, enable “Keys” and deselect “Values” and “Data” check boxes.

4. Press ENTER.

You’ll now be taken to the HKEY_CLASSES_ROOT\SystemFileAssociations branch.

Expand the “SystemFileAssociations” branch by double-clicking on it
Scroll down until you see a subkey named “image”
Double-click “image”

Double-click “shell”

Double-click “edit”

Double-click “command”


IDEA linux – import module hanging

I tried IDEA on linux. OF course, It started with gooling 😀

I tried to import the modules, but hanged… (on a freshly created project, with import maven modules)


The resolution was:

File -> invalidate caches and restart


Disabling UPS beep under Linux

But it will take about 3-5 minutes to make all the setup under Linux properly. We need to run a upscmd at last, but there are a few steps before that.

  • First of all, install nut package:
$ sudo apt install nut
  • Append following lines to /etc/nut/ups.conf according to your ups device (descparameter not important, you don’t need to give correct brand name either but the given section name will be used later to identify configured ups device, we’re using eaton as config section name here):
driver = usbhid-ups
port = auto
desc = "Eaton 5E"
  • Now start the upsdriver with upsdrvctl:
$ sudo upsdrvctl start
Network UPS Tools - UPS driver controller 2.7.4
Network UPS Tools - Generic HID driver 0.41 (2.7.4)
USB communication driver 0.33
  • Run upsc command the get beeper status:
$ upsc eaton ups.beeper.status
  • We’re so close, now append following lines to /etc/nut/upsd.users, change the username admin or password as you want:
password = "test1234"
actions = SET
instcmds = ALL
  • Reload upsd with the new users config:
$ sudo upsd -c reload
  • You can query the list of the commands which will be supported by your ups device with the upscmd:
$ upscmd -l eaton
Instant commands supported on UPS [eaton]:

beeper.disable - Disable the UPS beeper
beeper.enable - Enable the UPS beeper
beeper.mute - Temporarily mute the UPS beeper - Obsolete (use beeper.disable or beeper.mute)
beeper.on - Obsolete (use beeper.enable) - Turn off the load immediately - Turn off the load with a delay (seconds)
shutdown.stop - Stop a shutdown in progress
  • As you can see, there is a command named beeper.disable and we’ll be execute this command (give the username and password which we configured just before):
$ upscmd eaton beeper.disable
Username (root): admin
  • Now check the beeper status again:
$ upsc eaton ups.beeper.status

That’s it. It takes some time but your ears will be happy.