pikvm/docs/vnc.md

# VNC

As an alternative to the web interface, you can use VNC with various desktop clients. The main advantage of VNC over the browser is the ability to expand the image to the full screen, as well as complete interception of all keyboard keys. In some cases, VNC will be more responsive than the browser, especially on weak computers.

!!! warning
    Don't use VNC without X.509 or TLS encryption on untrusted networks! Otherwise your password will be transmitted over the network in plain text. Unfortunately, this is the reality of the VNC protocol.
    
??? note "VNC and its varients/TeamViewer/RDP to a system uses the target systems framebuffer IE local display, VNC usage for PiKVM accesses the stream, there will still be a 100-200MS latency and cannot be compared with the other software solutions.


## Enabling VNC on the PiKVM side

1. Switch PiKVM filesystem to read-write mode using command `rw`.

2. *Optional:* Change client's keyboard layout if you're using an non-US keyboard. To do this edit file `/etc/kvmd/override.yaml`:

    ```yaml
    vnc:
        keymap: /usr/share/kvmd/keymaps/ru
    ```

    All available keymaps are located in `/usr/share/kvmd/keymaps`:

    <img src="keymaps.png" />

3. *Optional:* This step is not nessessory if using TigerVNC. Some VNC clients (for example TightVNC) can't use user/password authentication. In this case you can enable passphrases mode in `/etc/kvmd/override.yaml`:

    ```yaml
    vnc:
        auth:
            vncauth:
                enabled: true
    ```

    To set passphrases edit file `/etc/kvmd/vncpasswd`.

4. Enable `kvmd-vnc` daemon. VNC will be available on the port 5900: `systemctl enable --now kvmd-vnc`.

5. Switch filesystem back to read-only: `ro`.


## Configuring the client

We recommend [TigerVNC](https://tigervnc.org) for a better experience on desktop.

Here are our recommended settings for TigerVNC:

* **Compression** tab:
    * Choose **Tight** encoding as preferred and color-level **Full**.
    * Disable automatic quality adjust settings **Auto Select**.
    * Enable **Allow JPEG compression**.
* **Security** tab:
    * Enable **None**, **X.509 TLS** and **Anonymous TLS** encryption (or choose one preferred mode).
    * Enable **Username and password** authentication.

For iOS and Android the recommended application is bVNC:

* [Google Play](https://play.google.com/store/apps/details?id=com.iiordanov.bVNC)
* [App Store](https://apps.apple.com/us/app/bvnc-pro/id1506461202)


## Unsupported clients

* **RealVNC** - Does not support most widely used open VNC protocol extensions.
* **Guacamole** - Incorrectly implements vencrypt, no JPEG compression.
* **Vinagre** - Incorrectly implements vencrypt.