pikvm/pages/flashing_os.md

Flashing the OS image

Download the appropriate memory card image from https://pikvm.org/download.html. Select it based on the board, platform, and the video capture device you are using. For example: choose v2-hdmi-rpi4.img.bz2 for Raspberry Pi 4 with HDMI-to-CSI capture bridge.

Note: right now, pre-compiled images are only available for the Raspberry Pi 4. In all other cases, you will need to build the operating system yourself. But don't worry, it's very simple.

Using Linux CLI

Decompress and flash image and follow to the final steps. Be careful when choosing your device path:

# bzip2 -d v2-hdmi-rpi4.img.bz2
# dd if=v2-hdmi-rpi4.img of=/dev/mmcblkX

Using balenaEtcher (Linux, MacOS and Windows)

1. Download and install balenaEtcher.

2. Even on modern computers it might be faster to first extract the compressed image first. A bug in a balenaEtcher prior to version 1.5.108 caused it to use large amounts of RAM and a tediously slow flashing process. Extract the image using your favorite archive software. If you don't have one that supports .bz2 images (on Windows for example) - 7-Zip is a great (free) choice.
   
   Flashing the compressed image directly: ~12 minutes; extracting first (~1 minute on an SSD) and flashing afterwards only takes ~3 minutes.

3. Run Balena Etcher:

   

4. Press Flash from file and select the image:

   

5. Insert the memory card into the card reader. Press Select target and choose your memory card:

   

6. Press Flash! button.

   

7. Wait for the process to finish. Get yourself a coffee or do some stretching. 😉 If an error occurs during flashing, repeat the process:

   

The final steps

1. When the process is complete, pull out the memory card and insert it into the Raspberry Pi. Connect the Raspberry Pi to the power supply. Your device will obtain the IP address via DHCP automatically.
   ❗Windows users: balenaEtcher will automatically safely remove the memory card. If you are using a Windows version prior to Windows 10 1809 and a different flashing software, you should do the safe remove manually.

2. After power-up, Pi-KVM OS generates unique SSH keys and certificates. Do not turn off the Raspberry Pi until it's fully booted.

3. Congratulations! Your Pi-KVM will be available via SSH (ssh root@<ip-address> with the password root by default) and HTTPS. In most networks you should be able to reach Pi-KVM via any browser with the URL https://pikvm/. If that doesn't work you'll need to find the IP address manually in your router and try it via https://<ip-address>. The default login username is admin with admin as the password). For HTTPS a self-signed certificate is used by default. Your browser will give you a warning about an invalid SSL certificate which you can safely ignore.

4. To change the root password use command passwd via SSH or webterm. To change Pi-KVM web password use kvmd-htpasswd set admin. As indicated on the login screen, you need to use rw to make the root filesystem writable before issuing these commands. After making changes, make sure to run the command ro to switch the filesystem back to read-only.

5. After installation, we recommend you to update your operating system:

   # rw
   # pacman -Syu
   # reboot
   

6. Pacman saves all installed packages in a compressed format so that you can roll back to the old version if something goes wrong. After you've updated and made sure everything works, it makes sense to clear the package cache so that it doesn't take up space on the SD card:

   # rw
   # pacman -Sc
   # ro
   

7. Important note for HDMI-USB dongle users only. Because of this, many video capture devices tell the server's video card that the HDMI cable is supposedly disconnected. This may lead to the fact that if you boot the server without an active stream, the server will not detect your capture card. This is easy to fix:

   • Switch filesystem to RW-mode:

     # rw
     

   • Edit file /etc/kvmd/override.yaml and add these lines:

     kvmd:
         streamer:
             forever: true
             cmd_append: [--slowdown]
     

   • Finish:

     # ro
     # systemctl restart kvmd
     

8. 27.08.2020 note about systemd: the latest version of Arch Linux has a slightly broken systemd. The problem is that SSH to the Pi-KVM host may not work the first time, but the second or third. The Pi-KVM build environment contains a workaround for this problem: in the file /etc/pam.d/system-login line -session optional pam_systemd.so is commented. This does not have any negative impact on the PI-KVM functionality, but if you want to, after fixing the systemd (in a couple of months with the next update), you can uncomment this line.

If you have any problems or questions, contact us using Discord: https://discord.gg/bpmXfz5

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