---
layout: post
author: Sam Hadow
tags: archlinux sysadmin
---

This blog post is a short guide to run and use [waydroid](https://github.com/waydroid/waydroid) on archlinux. 

# What is waydroid?

Waydroid is a container-based approach to boot a ful android system on a regular linux system with an x86 or ARM CPU, and so has less overhead than an android x86 virtual machine to run android apps on a linux system. Waydroid only works in a wayland session but it's still possible to use a nested session if you use X11, which will be covered in this guide.

# Installation guide

## Requirements

A kernel which comes with the `rust_binder` module is necessary to run waydroid, `linux-zen` kernel includes this module.

### Other kernels 

If you're using another kernel you can add it via DKMS (note that you can use another [aur helper](https://wiki.archlinux.org/title/AUR_helpers) than yay).

```bash
yay -S binder_linux-dkms
```

Then you can manually load it:

```bash
sudo modprobe binder-linux devices=binder,hwbinder,vndbinder
```

Or load it automatically at boot:

```bash
echo "binder_linux" > /etc/modules-load.d/binder_linux.conf
echo "options binder_linux devices=binder,hwbinder,vndbinder" > /etc/modprobe.d/binder_linux.conf
```

## Installing necessary packages:

```bash
sudo pacman -S waydroid
```

### [On X11]

If using X11, you'll need to run a nested wayland session, a simple solution is using cage. You could also use weston.

```bash
sudo pacman -S cage
```

## Initializing waydroid:

```bash
sudo waydroid init
```

Or with google apps support:

```bash
sudo waydroid init -s GAPPS
```

## Running waydroid

This command will automatically start the waydroid container and a session before showing the UI.

```bash
waydroid show-full-ui
```

Otherwise if you want a CLI, you have to start the container and then a session:

```bash
sudo systemctl start waydroid-container.service
waydroid session start
```

#### Useful commands

| Command                             | Purpose                        |
| :---------------------------------- | :----------------------------- |
| `waydroid session start`            | Starting a session             |
| `waydroid session stop`             | Stopping a session             |
| `waydroid status`                   | Checking Waydroid status       |
| `sudo waydroid upgrade`             | Upgrading the LineageOS image  |
| `waydroid app list`                 | Get the list of installed apps |
| `waydroid app install $path_to_apk` | Install an APK                 |
| `waydroid show-full-ui`             | Launch the GUI                 |
| `waydroid app launch $package_name` | Launch an app                  |
| `sudo waydroid shell`               | Launch a shell                 |
| `waydroid --help`                   | Display the help message       |
|

### [On X11]

On X11 waydroid container can be started but then all waydroid commands need to be run inside a nested wayland session.  
If you just need waydroid UI the simplest is with cage:

```bash
cage -- waydroid show-full-ui
```

If you need the command line then you need to have a console running inside a wayland session. For example with Konsole:

```bash
cage -- konsole
```

You can then type the commands the same as described above.

## Firewall rules and packet forwarding

You need some additional rules in your firewall if you want the network to work inside waydroid. For example with nftables you need these additional rules in your tables:

```
table inet filter {
        chain input {
                # -------------------------------- waydroid
                iifname "waydroid0" accept comment "Allow incoming network traffic from WayDroid"

        }

        chain forward {
                # -------------------------------- waydroid
                iifname "waydroid0" accept comment "Allow incomming network traffic from WayDroid"
                oifname "waydroid0" accept comment "Allow outgoing network traffic from WayDroid"
        }
        chain output {
        }
}

```

You also need to enable packet forwarding. To check if it's already enabled:

```bash
sysctl net.ipv4.ip_forward
sysctl net.ipv6.conf.all.forwarding
```

If it's not enabled you can permanently enable it in the file `/etc/sysctl.conf` by uncommenting the lines `net.ipv4.ip_forward=1` for IPv4 and `net.ipv6.conf.all.forwarding=1` for IPv6. Please note that in most cases you can for now just enable the IPv4 packet forwarding and ignore the IPv6 one.  
And to reload the configuration:  

```bash
sudo sysctl -p /etc/sysctl.conf
```

## Additional notes

#### 1) clipboard sharing

If you want to share the clipboard between a wayland session and waydroid UI you need to install the packages `python-pyclip` and `wl-clipboard`.  
It however won't work with X11 and nested wayland sessions.

#### 2) app stores

You might want to install [aurora store](https://gitlab.com/AuroraOSS/AuroraStore), an open source google play store client not requiring a google account. And an F-Droid client like [droidify](https://f-droid.org/en/packages/com.looker.droidify/).

#### 3) GPU

If you have an Intel or AMD GPU it should work out of the box. But if you have a NVIDIA GPU you'll need to enable software rendering. For that in `/var/lib/waydroid/waydroid.cfg` add the following:

```
[properties]
ro.hardware.gralloc=default
ro.hardware.egl=swiftshader
```

and then run:

```bash
sudo waydroid upgrade --offline
sudo systemctl restart waydroid-container.service
```

#### 4) Running ARM apps

ARM apps won't work at first if you have a x86 CPU, it'll say the app is incompatible for your device when trying to install it. To use arm apps you need to install a translation layer. It's recommanded to use `libndk` on AMD CPUs and `libhoudini` on Intel CPUs. To do that:

```bash
yay -S waydroid-script-git

sudo waydroid-extras install libndk 
# or
sudo waydroid-extras install libhoudini 

sudo systemctl restart waydroid-container.service
```

And if you're interested in learning more about Intel houdini you can have a look at [this presentation](https://media.defcon.org/DEF%20CON%2029/DEF%20CON%2029%20presentations/Brian%20Hong%20-%20Sleight%20of%20ARM%20-%20%20Demystifying%20Intel%20Houdini.pdf), and in [video](https://www.youtube.com/watch?v=kdd8dSifxvU)


#### 5) Disabling on screen keyboard

By default waydroid shows AOSP on screen keyboard, which is useless on a computer with a keyboard already, to disable it the setting is in `Settings > System > Languages & input > Physical keyboard > Use on-screen keyboard`

#### 6) SELinux

This module is necessary for waydroid to work:

```
module local-waydroid-nft 1.0;

require {
        type virtd_t;
        type iptables_t;
        class process { noatsecure rlimitinh siginh };
}

#============= virtd_t ==============
allow virtd_t iptables_t:process { noatsecure rlimitinh siginh };
```

You can compile it and load it with these commands (with the content above in a file `local-waydroid-nft.te`):

```bash
checkmodule -m -o local-waydroid-nft.mod local-waydroid-nft.te
semodule_package -o local-waydroid-nft.pp -m local-waydroid-nft.mod
semodule -i local-waydroid-nft.pp
```

And this script makes starting waydroid more convenient:

```bash
#!/bin/bash
sudo /usr/lib/waydroid/data/scripts/waydroid-net.sh start
cage -- waydroid show-full-ui
```

#### 7) Additional troubleshooting

Finally you might want to check the [archwiki](https://wiki.archlinux.org/title/Waydroid) directly if having issues with waydroid.  
And although it's quite old and contains some unecessary steps now, you can check [this guide](https://forum.garudalinux.org/t/ultimate-guide-to-install-waydroid-in-any-arch-based-distro-especially-garuda/15902) too.