Guides

MUD Hosting with open-source tools

Transitioning a MUD from local development to a production server requires a focus on persistence, security, and automated recovery. This guide outlines the deployment of a C-based MUD (like ROM, Circle, or Merc) to a modern Linux VPS, ensuring the process remains active after SSH sessions close and survives system reboots.

45-60 minutes5 steps
MUD Hosting with open-source tools hero illustration
1

Initial Server Hardening and Firewall Configuration

Before deploying the game, secure the server to prevent unauthorized access. Disable password authentication for SSH and configure the Uncomplicated Firewall (UFW) to only allow the SSH port and the specific MUD port.

security_setup.sh
sudo ufw default deny incoming
sudo ufw default allow outgoing
sudo ufw allow ssh
sudo ufw allow 4000/tcp
sudo ufw enable

⚠ Common Pitfalls

  • •Ensure you have SSH keys configured before disabling password auth or you will be locked out.
  • •Check if your hosting provider has an external hardware firewall that also needs the MUD port opened.
2

Install Build Dependencies and Toolchains

Legacy MUD codebases often require specific headers and build tools. Install the standard build-essential package along with zlib and crypt libraries commonly used for player file compression and password hashing.

install_deps.sh
sudo apt update
sudo apt install -y build-essential git zlib1g-dev libcrypt-dev telnet

⚠ Common Pitfalls

  • •Older codebases may require 32-bit compatibility libraries (gcc-multilib) if they use 32-bit pointers.
  • •Missing zlib1g-dev is the most common cause of compilation failure in ROM/Circle derivatives.
3

Automate Persistence with systemd

Do not run your MUD in a screen or tmux session for production. Use a systemd service unit to ensure the game starts automatically on boot and restarts immediately if the binary crashes.

/etc/systemd/system/mud.service
[Unit]
Description=MUD Game Engine
After=network.target

[Service]
Type=simple
User=muduser
WorkingDirectory=/home/muduser/mud/area
ExecStart=/home/muduser/mud/src/rom 4000
Restart=always
RestartSec=5
StandardOutput=append:/home/muduser/mud/log/system.log
StandardError=append:/home/muduser/mud/log/error.log

[Install]
WantedBy=multi-user.target

⚠ Common Pitfalls

  • •The WorkingDirectory must be the folder where the engine expects to find its 'area' or 'lib' files.
  • •Failure to set the 'User' field will result in the game running as root, which is a major security risk.
4

Configure Automated Backups

MUD player files (pfiles) are modified constantly. Implement a cron job that creates a timestamped archive of the player and area directories, then moves them to a separate directory or remote storage.

backup.sh
#!/bin/bash
BACKUP_DIR="/home/muduser/backups"
TIMESTAMP=$(date +%Y%m%d_%H%M%S)
cd /home/muduser/mud
tar -czf $BACKUP_DIR/mud_backup_$TIMESTAMP.tar.gz area/ pfiles/
find $BACKUP_DIR -type f -mtime +7 -delete

⚠ Common Pitfalls

  • •Storing backups on the same disk as the live game offers no protection against drive failure.
  • •Verify that the 'find' command doesn't delete your only valid backup if the script fails to run.
5

Log Rotation and Monitoring

MUDs generate massive text logs that can exhaust disk space. Configure logrotate to compress and prune old logs, and use a simple netcat check to verify the port is responding.

/etc/logrotate.d/mud
/home/muduser/mud/log/*.log {
    daily
    missingok
    rotate 14
    compress
    delaycompress
    notifempty
    create 0640 muduser muduser
}

⚠ Common Pitfalls

  • •If the MUD binary keeps log files open, logrotate may require the 'copytruncate' option to avoid breaking the file descriptor.
  • •Ensure the 'muduser' has write permissions to the log directory.

What you built

Your MUD is now configured as a resilient system service with automated recovery and basic security hardening. To complete the setup, point a domain or subdomain A record to your VPS IP address and perform a test crash to verify that systemd restarts the process as expected.