Fix KVMD not starting after updating piKVM

piKVM is amazing. I had one controlling an old desktop of mine for over 18 months with no issues. I decided to update its software and ran into some problems.

The first problem was pacman was returning a 404 when trying to update. I guess in the last year and a half the repository URL had changed. I had to edit /etc/pacman.conf and update the URL:

Server =
SigLevel = Required DatabaseOptional

After fixing that, running pacman -Syu and answering yes, I rebooted, but found that kvmd would not start. The first symptom: HTTP 500 from nginx. Digging in I found that two services were failing to start: kvmd-tc358743.service and kvm-otg.service.

v4l2-ctl[429]: Cannot open device /dev/kvmd-video, exiting
kvmd-otg[398]: RuntimeError: Can't find any UDC

With these two services bailing the web UI wouldn’t start. I checked the kernel log and the tc358743 device was not detected at all. I was about to give up and just reflash the device when I noticed two files in /boot: cmdline.txt.pacsave and config.txt.pacsave. I know from my experience in arch that it means I had some configurations get clobbered. Running a diff between the two I found some very important lines omitted:


I restored the .pacsave files and rebooted, and it worked! Everything came back.

Next time I won’t wait so long between software updates.

piKVM pushover startup script

I’ve had an issue where I wasn’t sure if my dynamic DNS provider registered properly. I then realized that I have a piKVM attached to one of my servers that boots on powerup, even if the server does not. I could utilize this piKVM to help me out.

Thanks to inspiration from Chris Dzombak I was able to whip up a little script that runs on startup. This script waits 5 minutes to allow for my firewall and modem to boot up, then sends a pushover notification to let me know the piKVM is online and what its external IP address is.

To get it working on the piKVM I had to enter into RW mode, write and save the script, add execute permissions to the script, then configure a systemd service to run the script at startup.

Here is the script, saved under /root/

#!/usr/bin/env bash
set -eu

#Wait 5 minutes to allow router bootup
sleep 300

MESSAGE="$(hostname) is online. External IP: $EXTERNAL_IP"

#Send pushover command to alert it's up and send its external IP
curl -s \
  --form-string "token=$TOKEN" \
  --form-string "user=$USER" \
  --form-string "message=$MESSAGE" \

Set executable: chmod +x /root/

Here is the systemd service, saved under /etc/systemd/system/boot-pushover-notification.service




Reload daemons & enable startup:

systemctl daemon-reload
systemctl enable boot-pushover-notification.service

Test by exiting rw mode and rebooting the piKVM:


It works really well!