• Official Site: http://www.pwnadventure.com/

YouTube Series
This setup is part of a video series covering the different hacks and challenges in this game.

• Let's Play/Hack - Pwn Adventure 3: Pwnie Island - part 1
• Setup Private Server with Docker - Pwn Adventure 3: part 2
• Information Gathering / Recon - Pwn Adventure 3: part 3
• Recover Game Classes with gdb - Pwn Adventure 3: part 4
• Hooking on Linux with LD_PRELOAD - Pwn Adventure 3: part 5
• Flying and our first Flag! (Cow King) - Pwn Adventure 3: part 6
• Teleporting and Hovering (Unbearable Revenge) - Pwn Adventure 3: part 7

Install Server

Requirements
From the official README:

• At least 2GB of RAM, more RAM will allow more instances to be run on a single machine
  
• The Game Server does not need any graphics hardware and runs purely on console. It is known to run well on Amazon AWS and Digital Ocean VPS instances.
  
• The Game Server requires a lot of RAM to run, but uses fork and copy-on-write memory to allow many instances to run on a single host.
  
• For a server with 2GB of RAM, it is not recommended to run more than 5 instances, but a server with 8GB of RAM can typically run as many as the CPU can handle.
  
• It is recommended to use 2-3 instances per CPU core if you have sufficient RAM. You may be able to run 4-5 instances per core, but doing so may introduce slight lag.
  
• The files for the client and server are over 2GB as well, so several GB of free disk space are required.
  

There are several ways to build and deploy your own server.

Option 1 - Original
One option is to download and follow the instructions included in the README of the official files. The download can be found on the official website here http://www.pwnadventure.com/#server.

Option 2 - Guide
@Beaujeant created an excellent, and easy to follow step-by-step guide. It was also the basis for building the docker image from Option 3. The guide can be found here: https://github.com/beaujeant/PwnAdventure3/blob/master/INSTALL-server.md.

Option 3 - Docker
This option is super easy, as long as docker and docker-compose are installed on a host. It makes it easy to run and tear down a server, without making changes to the actual host system.
First, gather all necessary files:
In order to run the server, docker and docker-compose have to be installed. Docker is moving fast, so it's a good idea to follow the current official steps for installation (which could also include to remove an older system version of docker):

• Docker CE Ubuntu: https://docs.docker.com/install/linux/docker-ce/ubuntu/.
• docker-compose: https://docs.docker.com/compose/install/
• make sure the current user is part of the docker group with: sudo usermod -a -G docker $USER. restart or re-login and verify with id that the user is part of the docker group.

Then simply build the image and launch the master and game server:
docker-compose up can also run in detached/background mode with -d.

Install Client
First download the client from the official website here: http://www.pwnadventure.com/#downloads
To get a client connected to the new server, the server.ini for the client has to be modified. The server launched with docker expects that hostnames master.pwn3 and game.pwn3 are being used (These could theoretically be changed in the docker/setup files).
The server.ini for the client has to look something like this:

[MasterServer]
 Hostname=master.pwn3
 Port=3333
 
 [GameServer]
 Hostname=game.pwn3
 Port=3000
 Username=
 Password=
 Instances=

Make sure that the client can reach these hosts, for example by adding them to the /etc/hosts file. In this example the server is running on 192.168.178.57 and the entry for them would be:

192.168.178.57  master.pwn3
 192.168.178.57  game.pwn3

Warning: Using an IP as Hostname in the server.ini does not work! I spent 2 hours trying to figure out what was wrong.
To stop the server, simply type docker-compose down.
Warning: The database file is not persistent - taking down the container resets everything. So backup first.

Troubleshooting

Error: docker-compose build
A: Get more disk space.
A: Your user is probably not part of the docker group or docker service not running. sudo usermod -a -G docker pwn3, verify with id. Or service docker restart.

File Integrity
Check if the archive is corrupted

PwnAdventure3 Client Errors
Connection Error: Unable to connect to master server
This probably means that the MasterServer is not reachable.

• Client issues:
  • Check the [MasterServer] entry in the client's server.ini
  • Can you ping master.pwn3 from the host from your system?
  • Is the IP correct in the /etc/hosts file?
• Server issues:
  • Is the server not running and listening on port 3333?
  • Check with sudo netstat -tulpn
    • Is the master server listening: tcp6 0 0 :::3333 :::* LISTEN 31913/docker-proxy
  • Check docker ps if the two containers are up
    • master server running? 880f93374070 pwn3server "/opt/pwn3/setup/mas…" 0.0.0.0:3333->3333/tcp, 5432/tcp pwnadventure3_master_1

Waiting in connection queue...
This means the MasterServer is reachable and is waiting now for a free GameServer that can be given to the client. This probably means that no GameServer is running, or was not able to connect to the MasterServer.

• Server issues:
  • Is a game server running and listening on port 3000-3005?
  • Check listening processes with sudo netstat -tulpn
  • tcp6 0 0 :::3000 :::* LISTEN 32160/docker-proxy
  • Is pwnadventure3_game_1 container running? Check with docker ps -a
    • 84343f81034f pwn3server "/opt/pwn3/setup/gam…" 0.0.0.0:3000-3010->3000-3010/tcp, 5432/tcp pwnadventure3_game_1
  • do you see the following line in the log from docker-compose up: line 1: 7 Killed ./PwnAdventure3Server; pwnadventure3_game_1 exited with code 137
    • GET MORE RAM!

Docker versions
These versions were used during testing as a host:

Screenshots