Mordhau Server Port Forwarding
Open all required UDP ports for a Mordhau dedicated server: 7777 (game), 27015 (Steam query), 15000 (beacon/discovery), and 7778 (RCON). All four are needed for full server browser visibility.
Mordhau Server Port Forwarding
Mordhau requires four UDP ports for full functionality. Missing any of them can prevent the server from appearing in the browser or from accepting player connections.
Required Ports
| Port | Protocol | Purpose |
|---|---|---|
| 7777 | UDP | Game traffic — primary player connections |
| 27015 | UDP | Steam server browser query |
| 15000 | UDP | Beacon / server discovery heartbeat |
| 7778 | UDP | RCON (remote console) |
All four ports are UDP. Mordhau does not require any TCP ports to be forwarded for normal operation (RCON also runs over UDP in Mordhau's implementation).
Opening Ports with UFW (Ubuntu/Debian)
sudo ufw allow 7777/udp
sudo ufw allow 27015/udp
sudo ufw allow 15000/udp
sudo ufw allow 7778/udp
sudo ufw reload
Verify all four are open:
sudo ufw status
Opening Ports with firewalld (CentOS/RHEL/Fedora)
sudo firewall-cmd --permanent --add-port=7777/udp
sudo firewall-cmd --permanent --add-port=27015/udp
sudo firewall-cmd --permanent --add-port=15000/udp
sudo firewall-cmd --permanent --add-port=7778/udp
sudo firewall-cmd --reload
Opening Ports with iptables
iptables -A INPUT -p udp --dport 7777 -j ACCEPT
iptables -A INPUT -p udp --dport 27015 -j ACCEPT
iptables -A INPUT -p udp --dport 15000 -j ACCEPT
iptables -A INPUT -p udp --dport 7778 -j ACCEPT
Persist with iptables-save > /etc/iptables/rules.v4.
Running Multiple Servers on One Machine
Each instance needs its own port set. Increment by 1 per instance:
| Instance | Game Port | Query Port | Beacon Port | RCON Port |
|---|---|---|---|---|
| Server 1 | 7777 | 27015 | 15000 | 7778 |
| Server 2 | 7778 | 27016 | 15001 | 7779 |
| Server 3 | 7779 | 27017 | 15002 | 7780 |
Set each via launch parameters: -Port=7778 -QueryPort=27016 -BeaconPort=15001
And in Game.ini: RconPort=7779
Cloud Provider Firewalls
If you're on AWS, DigitalOcean, Hetzner, Vultr, or similar providers, there is typically a cloud-level firewall (security groups or cloud firewall) that is separate from the OS firewall. Both layers must allow all four UDP ports. Check your provider's control panel if ports appear open at the OS level but are still unreachable.
Verify Ports Are Open
From an external machine:
nmap -sU -p 7777,27015,15000,7778 YOUR_SERVER_IP
All four should show as open or open|filtered. If any show closed, re-check your firewall rules.