mirror of
https://github.com/pikvm/pikvm
synced 2024-11-05 00:00:28 +00:00
48 lines
2.5 KiB
Markdown
48 lines
2.5 KiB
Markdown
|
# WebRTC
|
||
|
|
This is a new alternative video transfer mode available for Raspberry Pi 4 users with an HDMI-CSI bridge.
|
||
|
|
It uses H.264 encoding instead of MJPEG and provides significantly less traffic consumption.
|
||
|
|
|
||
|
|
# How to use
|
||
|
|
If you use an OS image built after 2021.06.10, this mode will be available to you by default.
|
||
|
|
If you are upgrading to an older version of the OS, you will need to manually enable the WebRTC gateway:
|
||
|
|
```
|
||
|
|
# systemctl enable --now kvmd-janus
|
||
|
|
```
|
||
|
|
Then restart the Web UI and then in the System menu you will see the video mode switch.
|
||
|
|
|
||
|
|
# Subtleties
|
||
|
|
The MJPEG video stream uses the same HTTP connection that you use to download the web interface.
|
||
|
|
This means that for remote access, you just need to forward ports 80 and 443 on your router.
|
||
|
|
|
||
|
|
In contrast, WebRTC is a completely different way of transmitting video.
|
||
|
|
It uses a P2P connection and UDP. This reduces network load, but makes it difficult to configure
|
||
|
|
- the server needs to know your network configuration in order to use it correctly.
|
||
|
|
|
||
|
|
To implement this, the Pi-KVM checks which of the network interfaces is used for the default gateway,
|
||
|
|
and also tries to find out your external address using the Google [STUN](https://en.wikipedia.org/wiki/STUN) server.
|
||
|
|
This is necessary when using [Tailscale](tailscale.md) or so that you can connect to your Pi-KVM from the external Internet,
|
||
|
|
since simply forwarding ports 80 and 443 for WebRTC is not enough - it requires a direct connection.
|
||
|
|
|
||
|
|
If you don't like using Google (it was chosen as the default for reliability reasons) for this purpose,
|
||
|
|
you can choose [any other STUN server](https://www.voip-info.org/stun/) at your discretion, or start your own.
|
||
|
|
Use `/etc/kvmd/override.yaml` to this:
|
||
|
|
```yaml
|
||
|
|
janus:
|
||
|
|
stun:
|
||
|
|
host: stun.stunprotocol.org
|
||
|
|
port: 3478
|
||
|
|
```
|
||
|
|
And restart `systemctl restart kvmd-janus`.
|
||
|
|
|
||
|
|
# KVMD-Janus vs. KVMD-Janus-Static
|
||
|
|
[Janus](https://janus.conf.meetecho.com) is a WebRTC gateway that is used to transmit the [uStreamer](https://github.com/pikvm/ustreamer) video.
|
||
|
|
KVMD-Janus is a wrapper around it, configuring and monitoring changes in the network configuration. This is suitable for most users.
|
||
|
|
However, if your Pi-KVM is not connected to the Internet and/or you want to use a custom Janus configuration,
|
||
|
|
then you should use the `kvmd-janus-static` service instead. You should first change the Janus configuration yourself.
|
||
|
|
You can find it in `/etc/kvmd/janus/janus.jcfg`.
|
||
|
|
```
|
||
|
|
# systemctl disable --now kvmd-janus
|
||
|
|
...
|
||
|
|
# systemctl enable --now kvmd-janus-static
|
||
|
|
```
|