Raspberry Pi stuff
🕰️ Check NTP first for all network weirdness. The lack of a real-time clock means that if NTP ever fails (or there’s been a power outage), the time drift can knock DNSSEC or other time-dependent services into failure pretty fast.
Shell aliases
Print the temperature in Fahrenheit (looks like this CPU Temp: 102°F)
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function pi-temp {
/usr/bin/vcgencmd measure_temp |\
awk -F "[=']" '{print($2 * 1.8)+32}' |\
awk -F "." '{print $1}' |\
echo "CPU Temp: $(cat)°F"
}
Video
Sometimes older DVI or VGA monitors don’t like HDMI adapters. They’ll show “No signal” or go dormant when the device is online and works on newer monitors. Editing /boot/config.txt to force HDMI hot-plug mode can sometimes help. Must reboot to apply the setting.
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hdmi_force_hotplug=1
Audio
🔉 For some reason, the kiddo pi desktops sometimes lose the sound device. When this happens, raspi-config shows no sound systems or devices and pulseaudio seems to have disappeared. This has fixed it a couple times now.
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# reinstall pulseaudio, then reboot
sudo apt reinstall pulseaudio
sudo reboot
# make sure it's using HDMI 0 for audio and pulseaudio shows up as an audio system
sudo raspi-config
# what's another reboot?
sudo reboot
# huh, no noise still ... run this and mess with the physical volume buttons
speaker-test
While I’m not using Arch, their wiki page on pulseaudio has great examples. This blog post on pulseaudio under the hood is good for explaining how it puts it all together for audio on Linux.