Networking Configuration

Proper network configuration is critical for your FluxNode to communicate reliably with the Flux network. This section covers both Single‑Node and Multi‑Node setups.

💡 Note: For the purpose of this guide, we’ll walk through the process using a VPS server rental scenario while configuring a Cumulus FluxNode. If you’re running FluxNode from home, steps may differ slightly. In this example, we’ll be using PuTTY as our SSH client to connect to the server.

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Single-Node Configuration

Recommended: UPnP

1. Reserve a Static IP

   • In your router’s DHCP settings, assign a fixed local IP to your node’s MAC address.

2. Disable Any Existing Port Forwarding

   • Remove old rules to avoid conflicts.

3. Enable UPnP on Your Router

   • Consult your router’s documentation for enabling Universal Plug‑and‑Play.

   • Reboot the router after enabling.

4. Configure the Node via Multitoolbox

   • SSH into your node and run:

     bashCopyEditmultitoolbox

   • Select Option 14: UPnP Port Configuration.

   • Choose an API port (start at 16127, then increment if needed).

🛡️ FluxOS includes a built‑in UFW firewall that will automatically open the necessary ports once UPnP mapping is established.

Alternative: DMZ

If UPnP is unavailable, you may place your node’s IP in the router’s DMZ (demilitarized zone), exposing all inbound traffic to the node. FluxOS’s UFW will still manage and restrict ports appropriately.

❗ Note: As of FluxOS v4.0.0, port forwarding is no longer recommended. See Release Notes v4.0.0.

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Multi-Node Configuration

The Flux network supports up to 8 nodes per single external IP. For multi‑node setups, UPnP is required; DMZ and manual port‑forwarding are generally unreliable on consumer routers.

1. Assign Static IPs

   • Reserve a unique local IP for each node instance.

2. Enable UPnP

   • As per the single‑node steps above.

3. Configure Distinct API Ports

   • For each node, run Option 14: UPnP Port Configuration in multitoolbox.

   • Assign a different API port to each node (e.g., 16127, 16128, … 16134).

💡 Ensure each node’s API port is unique to avoid address conflicts in UPnP mappings.