Can’t see /tmp/printer and not connect
Klipper by default adds a link /tmp/printer pointing to the correct device to connect to. If that link is owned by a different user then repetierserver and the /tmp folder has the +t flag set, we can not read and open the link due to permission problems. In that case you can either reference the device directly – normally /dev/pts/1 and everything will work.
Solution 1
If you have multiple klipper instances so it is not clear which device will point to which pts device, you can tell klipper where to place that link with -I flag.
New systemd solution
Current klipper versions use a systemd service file to create a service. Here the solution is to change the user running klipper to “repetierserver” and the permission problems with /tmp/printer are gone. So log in via ssh and follow the instructions.
Stop klipper service
sudo service klipper stop
Edit klipper service to run as user repetierserver
sudo nano /etc/systemd/system/klipper.service
Replace old content
#Systemd service file for klipper [Unit] Description=Starts klipper on startup After=network.target [Install] WantedBy=multi-user.target [Service] Type=simple User=pi RemainAfterExit=yes ExecStart=/home/pi/klippy-env/bin/python /home/pi/klipper/klippy/klippy.py /home/pi/printer.cfg -l /tmp/klippy.log Restart=always RestartSec=10#Systemd service file for klipper [Unit] Description=Starts klipper on startup After=network.target
Into the following one where we only changed the User= line:
[Install] WantedBy=multi-user.target [Service] Type=simple User=repetierserver RemainAfterExit=yes ExecStart=/home/pi/klippy-env/bin/python /home/pi/klipper/klippy/klippy.py /home/pi/printer.cfg -l /tmp/klippy.log Restart=always RestartSec=10
Remove old files which were created by the user “pi”
sudo rm /tmp/klippy.log sudo rm /tmp/printer
Recreate the service and start klipper
sudo systemctl daemon-reload sudo service klipper start
Now you can select /tmp/printer as serial device in Repetier-Server and connection should work.
Old init.d solution
Older klipper versions used a service defined in /etc/init.d/klipper – for these use this solution-
Default is in /etc/default/klipper and can be changed there. So create a folder writeable by Klipper, e.g.
sudo mkdir /var/lib/klipper sudo chmod 777 /var/lib/klipper
And then modify in /etc/default/klipper
KLIPPY_ARGS="/home/pi/klipper/klippy/klippy.py /home/pi/printer.cfg -l /tmp/klippy.log"
into
KLIPPY_ARGS="/home/pi/klipper/klippy/klippy.py /home/pi/printer.cfg -l /tmp/klippy.log -I /var/lib/klipper/connect"
And then also enter /var/lib/klipper/connect manually in Repetier-Server port name. After restarting Klipper Repetier-Server should now see the link and open it without problems.
Alternative solution
The alternative solution that works as well as the replaced link is to start klipper as repetierserver user. Edit /etc/default/klipper and set
KLIPPY_USER=repetierserver
and restart klipper. Now both have the same user and no permission problems exist.
