Arma Reforger Port Forwarding Guide: Open Ports for Server Hosting

Port forwarding is essential for hosting an Arma Reforger server that players can connect to from the internet. This comprehensive guide covers everything you need to know about opening ports, configuring your router, and troubleshooting connection issues.

Understanding Port Forwarding

Port forwarding (also called "port mapping") tells your router to forward incoming connections on specific ports to your server computer.

Why Port Forwarding is Necessary

Without port forwarding:

• Your server is hidden behind your router's firewall
• External players cannot connect
• Server doesn't appear in the server browser
• Only LAN players can join

With port forwarding:

• ✅ Server is accessible from the internet
• ✅ Appears in public server browser
• ✅ Players worldwide can connect
• ✅ Proper network communication

How Port Forwarding Works

Internet → Your Router → Your Server PC (Port 2001)
           ^^^^^^^^^^
           Port forwarding rule here

When a player tries to connect:

1. Connection request arrives at your router
2. Router checks port forwarding rules
3. If port 2001 is forwarded to your server PC
4. Request is sent to your server
5. Server responds and connection is established

Required Ports for Arma Reforger

Arma Reforger uses multiple ports for different purposes.

Essential Ports

CRITICAL: Port 2001 MUST be forwarded for your server to work!

Optional Ports

Note: A2S port improves server listing accuracy. RCON port only needed if using remote admin tools.

Custom Ports

You can change the default port 2001 to any other port in config.json:

{
  "bindPort": 2345,
  "publicPort": 2345
}

When to use custom ports:

• Port 2001 is blocked by your ISP
• Running multiple servers on same machine
• Avoiding port conflicts with other applications

Important: If you change ports, forward the NEW port instead of 2001!

Prerequisites

Before configuring port forwarding, gather this information:

1. Your Server's Local IP Address

Windows:

1. Open Command Prompt
2. Type: ipconfig
3. Find "IPv4 Address" (usually 192.168.x.x or 10.0.x.x)

ipconfig

Ethernet adapter:
   IPv4 Address. . . . . . : 192.168.1.100  ← This is your local IP
   Subnet Mask . . . . . . : 255.255.255.0
   Default Gateway . . . . : 192.168.1.1

Linux:

ip addr show

# Or
ifconfig

# Look for inet address like: 192.168.1.100

2. Your Router's IP Address (Gateway)

This is the "Default Gateway" from the ipconfig/ifconfig output above.

Common router IPs:

• 192.168.1.1 (most common)
• 192.168.0.1
• 10.0.0.1
• 192.168.1.254

3. Router Admin Credentials

You'll need:

• Router admin username (often "admin")
• Router admin password (check sticker on router, or ISP documentation)

Lost password? Most routers have a reset button on the back.

Accessing Your Router Settings

Step 1: Open Router Admin Panel

1. Open web browser
2. Enter router IP in address bar: http://192.168.1.1
3. Press Enter

Step 2: Login

Common default credentials:

• Username: admin | Password: admin
• Username: admin | Password: password
• Username: admin | Password: (blank)
• Username: (blank) | Password: admin

Check your router's label for specific credentials!

Step 3: Find Port Forwarding Section

Location varies by router, look for:

• "Port Forwarding"
• "Virtual Server"
• "NAT / Gaming"
• "Applications & Gaming"
• "Firewall → Port Forwarding"
• "Advanced → Port Forwarding"

Port Forwarding Configuration

Basic Port Forward Rule

Create a new port forwarding rule with these settings:

Rule Name: Arma Reforger Server

External Port: 2001 Internal Port: 2001 Internal IP: 192.168.1.100 (your server's local IP) Protocol: Both (TCP + UDP) or select UDP and TCP separately

Complete Configuration Example

Most routers have a form like this:

Service Name:        Arma Reforger Server
External Port Start: 2001
External Port End:   2001
Internal Port Start: 2001
Internal Port End:   2001
Protocol:            Both (TCP/UDP)
IP Address:          192.168.1.100
Enabled:             ✅ Yes

Adding Multiple Ports (Game + A2S + RCON)

If you want all ports forwarded:

Rule 1: Game Port

Name:     Arma Reforger Game
External: 2001
Internal: 2001
IP:       192.168.1.100
Protocol: Both

Rule 2: A2S Query

Name:     Arma Reforger A2S
External: 17777
Internal: 17777
IP:       192.168.1.100
Protocol: UDP

Rule 3: RCON

Name:     Arma Reforger RCON
External: 19999
Internal: 19999
IP:       192.168.1.100
Protocol: TCP

Save and Apply

1. Click "Save" or "Apply"
2. Router may restart (wait 30-60 seconds)
3. Verify settings were saved

Router-Specific Guides

TP-Link Routers

1. Go to http://192.168.1.1
2. Login (default: admin/admin)
3. Navigate to Advanced → NAT Forwarding → Virtual Servers
4. Click Add
5. Fill in port forwarding details
6. Click Save

Netgear Routers

1. Go to http://192.168.1.1
2. Login (default: admin/password)
3. Navigate to Advanced → Advanced Setup → Port Forwarding/Port Triggering
4. Select Port Forwarding
5. Click Add Custom Service
6. Fill in details
7. Click Apply

Linksys Routers

1. Go to http://192.168.1.1
2. Login (default: admin/admin)
3. Navigate to Applications & Gaming → Port Range Forward
4. Fill in first available row
5. Click Save Settings

ASUS Routers

1. Go to http://192.168.1.1
2. Login
3. Navigate to WAN → Virtual Server / Port Forwarding
4. Click Add Profile
5. Fill in details
6. Click Apply

Google Wi-Fi / Nest Wi-Fi

1. Open Google Home app on phone
2. Tap Wi-Fi → Settings → Advanced Networking
3. Tap Port management
4. Tap Create port forwarding rule
5. Fill in details
6. Save

ISP-Provided Routers (Xfinity, AT&T, etc.)

Xfinity xFi Gateway:

1. Visit https://xfinity.com/myrouter
2. Login with Xfinity account
3. Go to Advanced Settings → Port Forwarding
4. Add rule

AT&T Gateway:

1. Go to http://192.168.1.254
2. Login
3. Navigate to Firewall → NAT/Gaming → Custom Services
4. Add service

Setting Static IP (Recommended)

Port forwarding rules break if your server's local IP changes. Prevent this with a static IP.

Method 1: Router DHCP Reservation (Preferred)

Most reliable method - assigns same IP every time:

1. Find your server's MAC address:

   • Windows: ipconfig /all → "Physical Address"
   • Linux: ip link show → "link/ether"

2. In router settings, find:

   • "DHCP Reservation"
   • "Address Reservation"
   • "Reserved IP Addresses"

3. Add reservation:

   MAC Address: AA:BB:CC:DD:EE:FF
   IP Address:  192.168.1.100
   Description: Arma Reforger Server
   

4. Save and restart router

Method 2: Static IP on Server (Windows)

1. Open Network Connections
2. Right-click network adapter → Properties
3. Select Internet Protocol Version 4 (TCP/IPv4)
4. Click Properties
5. Select Use the following IP address:
   • IP address: 192.168.1.100
   • Subnet mask: 255.255.255.0
   • Default gateway: 192.168.1.1 (your router IP)
   • Preferred DNS: 8.8.8.8
   • Alternate DNS: 8.8.4.4
6. Click OK

Method 3: Static IP on Server (Linux)

Edit netplan configuration (Ubuntu/Debian):

sudo nano /etc/netplan/01-netcfg.yaml

Add:

network:
  version: 2
  ethernets:
    eth0:  # Or your interface name
      addresses:
        - 192.168.1.100/24
      gateway4: 192.168.1.1
      nameservers:
        addresses: [8.8.8.8, 8.8.4.4]

Apply:

sudo netplan apply

Testing Port Forwarding

Test 1: Online Port Checker

Before starting server:

1. Visit https://www.yougetsignal.com/tools/open-ports/
2. Enter your public IP (find at https://whatismyip.com)
3. Enter port: 2001
4. Click "Check"
5. Should show "closed" (server not running yet)

After starting server:

1. Start Arma Reforger server
2. Repeat port check
3. Should now show "open" ✅

Test 2: Server Browser

1. Start server with visible: true in config
2. Wait 5 minutes for registration
3. Search for your server name in game's server browser
4. If it appears, port forwarding works!

Test 3: Direct Connection

1. Start server
2. Find your public IP: https://whatismyip.com
3. In Arma Reforger client: Play → Direct Connect
4. Enter: YOUR_PUBLIC_IP:2001
5. If connection succeeds, ports are open!

Test 4: A2S Query (Optional)

If you forwarded port 17777:

1. Visit https://gameserverstatus.com
2. Select "Arma Reforger"
3. Enter your public IP and port 17777
4. Should show server info if A2S is working

Troubleshooting

Port Shows "Closed" Despite Forwarding

Check 1: Server Running

• Port only shows open when server is actively running
• Start server, then test again

Check 2: Correct Internal IP

• Verify server's local IP hasn't changed
• Run ipconfig / ip addr again
• Update port forwarding rule if changed

Check 3: Protocol

• Ensure protocol is set to "Both" or both "UDP" AND "TCP"
• Some routers require separate rules for UDP and TCP

Check 4: Router Reboot

• Some routers don't apply settings until reboot
• Restart router and test again

Check 5: Firewall

• Windows Firewall may block despite port forwarding
• See Firewall Configuration section below

Server Not in Browser

Possible causes:

1. Backend registration failed

   • Check server logs for errors
   • Verify visible: true in config.json

2. Ports not forwarded correctly

   • Double-check port forwarding rules
   • Test with online port checker

3. ISP blocks hosting

   • Some ISPs block hosting servers
   • Try different port (not 2001)
   • Contact ISP support

4. Waiting period

   • New servers take 5-10 minutes to appear
   • Be patient!

Players Can't Connect

Scenario 1: Not in browser, can't direct connect

• Port forwarding incomplete
• Firewall blocking
• Server not running

Scenario 2: In browser, but can't connect

• Check BattlEye settings
• Verify mod compatibility
• Check server logs for errors

Scenario 3: Some players can connect, others can't

• Their firewall/antivirus blocking
• Their ISP issues
• Not a server problem

Firewall Configuration

Even with port forwarding, firewalls can block connections.

Windows Firewall

Method 1: Allow App

1. Open Windows Defender Firewall
2. Click Allow an app through firewall
3. Click Change settings
4. Click Allow another app
5. Browse to ArmaReforgerServer.exe
6. Check both Private and Public
7. Click Add

Method 2: Manual Rules (more control)

# Run as Administrator

# UDP Rule
netsh advfirewall firewall add rule name="Arma Reforger Server UDP" dir=in action=allow protocol=UDP localport=2001

# TCP Rule
netsh advfirewall firewall add rule name="Arma Reforger Server TCP" dir=in action=allow protocol=TCP localport=2001

# A2S (optional)
netsh advfirewall firewall add rule name="Arma Reforger A2S" dir=in action=allow protocol=UDP localport=17777

# RCON (optional)
netsh advfirewall firewall add rule name="Arma Reforger RCON" dir=in action=allow protocol=TCP localport=19999

Linux Firewall (UFW)

# Allow game port
sudo ufw allow 2001/udp
sudo ufw allow 2001/tcp

# Allow A2S (optional)
sudo ufw allow 17777/udp

# Allow RCON (optional)
sudo ufw allow 19999/tcp

# Reload firewall
sudo ufw reload

Linux Firewall (iptables)

# UDP game port
sudo iptables -A INPUT -p udp --dport 2001 -j ACCEPT

# TCP game port
sudo iptables -A INPUT -p tcp --dport 2001 -j ACCEPT

# Save rules
sudo iptables-save > /etc/iptables/rules.v4

Alternative Solutions

UPnP (Automatic Port Forwarding)

Some routers support UPnP (Universal Plug and Play) for automatic port forwarding.

Enable UPnP on Router:

1. Access router settings
2. Find "UPnP" setting (often under Advanced/Network)
3. Enable it
4. Save

Arma Reforger Server may automatically open ports via UPnP.

Pros:

• ✅ Automatic, no manual configuration
• ✅ Works across router changes

Cons:

• ❌ Security risk (malware can open ports)
• ❌ Not all routers support it
• ❌ Less reliable than manual forwarding

Recommendation: Use manual port forwarding for production servers.

DMZ (Not Recommended)

DMZ (Demilitarized Zone) exposes ALL ports to the internet.

How it works:

1. Router settings → DMZ
2. Enter server's local IP
3. All ports open to that IP

Pros:

• ✅ Guaranteed to work
• ✅ No port configuration needed

Cons:

• ❌ Major security risk - all ports exposed
• ❌ Server vulnerable to attacks
• ❌ Not recommended for shared PCs

Only use DMZ if:

• Server is dedicated machine (not personal PC)
• You understand security implications
• All other methods failed

VPN Tunneling (Advanced)

Services like Hamachi or ZeroTier create virtual networks.

Pros:

• ✅ No port forwarding needed
• ✅ Works with restrictive ISPs

Cons:

• ❌ Players must install VPN client
• ❌ Added latency
• ❌ Complex setup

Not recommended for public servers.

Reverse Proxy / Tunnel Services

Services like ngrok, Cloudflare Tunnel, or playit.gg can expose your server.

Pros:

• ✅ No router configuration
• ✅ Works behind CGNAT

Cons:

• ❌ May add latency
• ❌ Some services charge fees
• ❌ Less control

ISP Considerations

CGNAT (Carrier-Grade NAT)

Some ISPs use CGNAT, which prevents port forwarding.

How to check if you have CGNAT:

1. Find your public IP: https://whatismyip.com
2. Compare to your router's WAN IP (in router settings)
3. If they DON'T match, you have CGNAT

Solutions for CGNAT:

• Contact ISP for "public IP address" upgrade (may cost extra)
• Use VPS hosting instead of home hosting
• Use tunnel services (playit.gg, etc.)

Port Blocking

Some ISPs block common hosting ports (including 2001).

Test:

• Try forwarding different port (e.g., 27015)
• Update config.json to use new port
• If works, your ISP blocks port 2001

Solution:

• Use non-standard port in config.json
• Contact ISP to unblock port

Best Practices

1. Use DHCP reservation instead of static IP on PC
2. Document your settings - screenshot router config
3. Test after any router firmware update - settings may reset
4. Use strong router password - don't leave as "admin"
5. Keep router firmware updated - security patches
6. Monitor logs - watch for unauthorized access attempts
7. Disable UPnP if using manual forwarding (security)

Quick Troubleshooting Checklist

• ✅ Server is running
• ✅ Port forwarding rule exists in router
• ✅ Internal IP is correct and hasn't changed
• ✅ Protocol set to "Both" or both UDP+TCP
• ✅ Router settings saved and applied
• ✅ Router rebooted after changes
• ✅ Windows/Linux firewall allows ports
• ✅ Server shows "open" on port checker
• ✅ Config.json has correct bindPort/publicPort
• ✅ Server logs show no binding errors

Helpful Resources

• Server Setup Guide
• Config Troubleshooting
• Config Generator
• Port Checker Tool
• What Is My IP?

Last Updated: November 2025

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