I’m going to restart from scratch to confirm that I have the privileges, because I’ve deleted and re-added so many commands that I’d rather try again.
But I’m pretty sure that originally I used the command you validated for me and therefore there’s no connection to the serial Node
here is the command :
I’ll get back to you 
Good evening @pierre-gilles
@Psoy I just found this (maybe you already have): https://stackoverflow.com/questions/24225647/docker-a-way-to-give-access-to-a-host-usb-or-serial-device
You need to scroll down to The Safe and Proper way of accessing tty devices without *--privileged* mode
Reading the rest it looks pretty good but I don’t have anything to test at home, so we’ll see how it works on your host.
Basically, each time you replug your rflink, a script runs to attach
Good evening @mutmut
I didn’t see what you found, I worked with Gemini to understand why the serial
@Psoy As which user are you launching the Gladys container?
If you want the --privileged to work, the user must be root.
I think that’s not the case on your system!
Are you indeed running sudo docker run... ?
Indeed I wasn’t typing sudo before docker run 
.
So I retyped the docker run command with sudo in front, and I repeated the procedure three times to be sure, but even with sudo the permissions of the USB0 port don’t change and remain as follows
crw-rw---- 1 root dialout 188, 0 Feb 21 09:59 /dev/ttyUSB0
lrwxrwxrwx 1 root root 7 Feb 21 09:59 /dev/tty-usb-arduinoThat’s normal, the permissions of the USB0 port are supposed to stay like that.
The permissions here show that the user « root » is the owner of this USB port; but if you started your container as root, you should therefore be the owner of the USB port.
Now, you only started the Gladys container, and the Node-RED container was started by Gladys. Maybe the Node-RED container wasn’t started as root.
Can you check which user started the Gladys container, and compare it with the user that started the Node-RED container?
(I’ll let you use Google/AI to find the right commands to do that 
)
ah yes that’s how you learn 
From what I just tested, all the commands are run on the host, not inside the Gladys Docker.
First your Gladys and Node-RED Docker containers must be running.
Then to see if it works you can test:
docker ps -qf name=node-red
and it should return a number/id (that of your Node-RED docker).
If that’s not the case, we won’t continue and you can check if the dockers are running with docker ps
So on the host, you can create (with your preferred text editor):
sudo nano /etc/udev/rules.d/99-docker-tty.rules
then copy/paste:
ACTION=="add", SUBSYSTEM=="tty", RUN+="/usr/local/bin/docker_tty.sh 'added' '%E{DEVNAME}' '%M' '%m'"
ACTION=="remove", SUBSYSTEM=="tty", RUN+="/usr/local/bin/docker_tty.sh 'removed' '%E{DEVNAME}' '%M' '%m'"
If it’s nano, do ctrl+X and Y (or O) and Enter to save and exit.
Then to apply the rules:
sudo udevadm control --reload
Finally you need to create the script that will automatically mount and unmount the device on the USB port:
sudo nano /usr/local/bin/docker_tty.sh
and paste:
#!/usr/bin/env bash
echo "Usb event: $1 $2 $3 $4" \u003e\u003e /tmp/docker_tty.log
if [ ! -z "$(docker ps -qf name=node-red)" ]
then
if [ "$1" == "added" ]
then
docker exec -u 0 env_dev mknod $2 c $3 $4
docker exec -u 0 env_dev chmod -R 777 $2
echo "Adding $2 to docker" \u003e\u003e /tmp/docker_tty.log
else
docker exec -u 0 env_dev rm $2
echo "Removing $2 from docker" \u003e\u003e /tmp/docker_tty.log
fi
fi
Set the execution rights on this script:
sudo chmod +x /usr/local/bin/docker_tty.sh
And you can then see what happens by plugging in your USB device (notably in /tmp/docker_tty.log).
If nothing works, there’s a command to run but I don’t know exactly what it does (I have my limits ):
docker run --device-cgroup-rule='c 188:* rmw' -itd --name my_container ubuntu
And that’s what my link indicates to do first. I think it launches an Ubuntu with a container that will be named my_container and we pass it an argument. However, I don’t know whether to run this command on the Gladys docker or on the Node-RED docker, and knowing that the Node-RED docker will be started, I don’t know if it will work …
Anyway, it can get stuck at that point.
In any case, tell me whether the first tests are conclusive.
EDIT: after that I’d be tempted to tell you not to go through Gladys to create/launch the Node-RED docker but to create one separately and then you can run the odd command in that docker.
Good evening @pierre-gilles @mutmut
Can you confirm that the image name of the gladys- node-red container is indeed nodered/node-red:3.1?
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
702448e6dba6 nodered/node-red:3.1 \"./entrypoint.sh\" 5 minutes ago Up 5 minutes (healthy) 0.0.0.0:1881-\u003e1880/tcp, :::1881-\u003e1880/tcp gladys-node-red
e000d717481c gladysassistant/gladys:node-red-usb-ports \"docker-entrypoint.s…\" 7 minutes ago Up 7 minutes gladys
c12621b8b474 containrrr/watchtower \"/watchtower --clean…\" 4 weeks ago Up 9 minutes (healthy) 8080/tcp watchtower
first I have to initialize the permissions (with CHMOD) because at startup they are not correct
I just tried unplugging and replugging the rflink several times but it doesn’t work, it doesn’t reconnect by itself.
I’m pasting the logs from /tmp/docker_tty.log
pi@rasp3b:/tmp $ sudo nano docker_tty.log
GNU nano 5.4 docker_tty.log
Usb event: added /dev/tty14 4 14
Usb event: added /dev/tty15 4 15
Usb event: added /dev/tty16 4 16
Usb event: added /dev/tty17 4 17
Usb event: added /dev/tty18 4 18
Usb event: added /dev/tty20 4 20
Usb event: added /dev/tty2 4 2
Usb event: added /dev/tty22 4 22
Usb event: added /dev/tty24 4 24
Usb event: added /dev/tty19 4 19
Usb event: added /dev/tty21 4 21
Usb event: added /dev/tty23 4 23
Usb event: added /dev/tty25 4 25
Usb event: added /dev/tty26 4 26
Usb event: added /dev/tty27 4 27
Usb event: added /dev/tty29 4 29
Usb event: added /dev/tty28 4 28
Usb event: added /dev/tty3 4 3
Usb event: added /dev/tty30 4 30
Usb event: added /dev/tty31 4 31
Usb event: added /dev/tty32 4 32
Usb event: added /dev/tty33 4 33
Usb event: added /dev/tty34 4 34
Usb event: added /dev/tty35 4 35
Usb event: added /dev/tty36 4 36
Usb event: added /dev/tty37 4 37
Usb event: added /dev/tty38 4 38
Usb event: added /dev/tty39 4 39
Usb event: added /dev/tty4 4 4
Usb event: added /dev/tty40 4 40
Usb event: added /dev/tty41 4 41
Usb event: added /dev/tty42 4 42
Usb event: added /dev/tty43 4 43
Usb event: added /dev/tty44 4 44
Usb event: added /dev/tty45 4 45
Usb event: added /dev/tty46 4 46
Usb event: added /dev/tty47 4 47
Usb event: added /dev/tty48 4 48
Usb event: added /dev/tty49 4 49
Usb event: added /dev/tty5 4 5
Usb event: added /dev/tty50 4 50
Usb event: added /dev/tty51 4 51
Usb event: added /dev/tty52 4 52
Usb event: added /dev/tty53 4 53
Usb event: added /dev/tty54 4 54
Usb event: added /dev/tty55 4 55
Usb event: added /dev/tty56 4 56
Usb event: added /dev/tty57 4 57
Usb event: added /dev/tty58 4 58
Usb event: added /dev/tty59 4 59
Usb event: added /dev/tty6 4 6
Usb event: added /dev/tty60 4 60
Usb event: added /dev/tty61 4 61
Usb event: added /dev/tty62 4 62
Usb event: added /dev/tty63 4 63
Usb event: added /dev/tty7 4 7
I don’t see a ttyUSB port, does that ring a bell?
I unplugged my Rflink several times.
I tried passing this command --device-cgroup-rule='c 188:* rmw' in the docker run, but it still doesn’t give permissions to the USB ports.
Then I added this command --device=/dev/ttyUSB0 \\ to the
docker run and that gives permissions to the USB port and the serial node connects fine.
However, it’s the same when we unplug the rflink: the USB port loses those permissions and reverts to crw-rw---- 1 root dialout 188, 0 Feb 21 22:52 /dev/ttyUSB0 instead of crw-rw-rw- 1 root dialout 188, 0 Feb 21 22:52 /dev/ttyUSB0
yes that’s correct.
So you should add your chmod in the script that keeps the variables, and if that doesn’t work, replace chmod a+rw $2 with chmod a+rw /dev/ttyUSB0 hard-coded:
#!/usr/bin/env bash
echo \"Usb event: $1 $2 $3 $4\" >> /tmp/docker_tty.log
if [ ! -z \"$(docker ps -qf name=gladys-node-red)\" ]
then
if [ \"$1\" == \"added\" ]
then
chmod a+rw $2
docker exec -u 0 gladys-node-red mknod $2 c $3 $4
docker exec -u 0 gladys-node-red chmod -R 777 $2
echo \"Adding $2 to docker\" >> /tmp/docker_tty.log
else
docker exec -u 0 gladys-node-red rm $2
echo \"Removing $2 from docker\" >> /tmp/docker_tty.log
fi
fi
EDIT: oops, I forgot to change env_dev to gladys-node-red in the script, it must not have been working well 
hello @mutmut
What do $1 $2 $3 $4 represent?
looking at the script that writes to the tmp, I’d say:
Usb event: added /dev/tty40 4 40
$1 = added (or removed)
$2 = /dev/tty40
$3 = 4
$4 = 40
However, no idea what $3 and $4 represent.
We should see /dev/ttyUSB when running lsusb but it won’t appear in the script’s log (and it will be a symbolic link if I’m not mistaken).
for me the symbolic link is this
/dev/tty-usb-arduino-nano
which points to /dev/ttyUSB0
Great, it works, I’ll do some tests tonight, but apparently by unplugging and replugging the Rflink, it disconnects and reconnects 
Is this solution going to be added to Gladys?
I uninstalled Gladys and Node-RED then reinstalled them, but I did not delete the two files that were created. After reboot the RFLink reconnects correctly.
I tested on a Raspberry 3B+. Will this solution work on a mini PC?
Good news!
For the script, I grabbed it for Debian on PC, so if it works on your Raspberry Pi, there’s no reason it shouldn’t.