Set Up a LAN for Field Operations

Build a reliable local network for your Field Day site so every station can reach FD Commander.

How-To Guides › LAN Setup

What You Need

FD Commander runs on your local network. Every device that needs to log contacts, view scores, or sign the guestbook connects to the same LAN. No internet required.

  • A Wi-Fi router. A cheap home router works fine.
  • The server running FD Commander (a Raspberry Pi, laptop, or any Linux box).
  • Client devices with a web browser (laptops, tablets, phones).
  • An ethernet cable to connect the server to the router.

Setting It Up

1 Power on the router. Leave the WAN/internet port empty. You don't need upstream connectivity.

2 Plug the FD Commander server into a LAN port on the router with an ethernet cable.

3 Connect client devices to the router's Wi-Fi network.

4 Open a browser on any client and go to the server's IP address.

That's the whole setup. The router handles DHCP (assigning IP addresses) and Wi-Fi. The server runs FD Commander. Clients open a browser and connect.

Tip

If your router has an "AP mode" or "bridge mode," use it. Some routers get confused when their WAN port has no link and will periodically stall trying to reach an upstream gateway.

Give the Server a Static IP

Your router hands out IP addresses automatically, but the server's address could change if it reboots. Give it a fixed address so every browser tab pointed at it keeps working.

The easiest way is a DHCP reservation. Log into your router's admin page and assign a fixed IP to the server's MAC address. The server still gets its address from the router, but the router always gives it the same one. Most routers support this under a "DHCP reservation" or "address reservation" setting.

If your router doesn't support reservations, you can set a static IP on the server itself. On a Raspberry Pi or Ubuntu system:

# Find your interface name (usually eth0) ip link show # Set a static IP sudo nmcli con mod "Wired connection 1" \ ipv4.addresses 192.168.1.50/24 \ ipv4.gateway 192.168.1.1 \ ipv4.method manual # Apply the change sudo nmcli con up "Wired connection 1"

Pick an address outside your router's DHCP range so it won't conflict with automatically assigned addresses. Check your router's admin page to see what range it uses.

Accessing FD Commander

Once the server has a static IP, clients just type it into a browser: http://192.168.1.50 (or whatever address you chose). That's it.

If you're running FD Commander on a Raspberry Pi, mDNS may already be working, which means devices can reach it at http://raspberrypi.local without knowing the IP. If you want a custom name, change the Pi's hostname.

Tip

Write the server's address on a piece of paper and tape it to the table at each station. Simple works.

Wi-Fi Tips

Wi-Fi at a Field Day site is fighting against HF transmitters, generators, and whatever else is producing RF. A few things help:

  • Use 5 GHz if you can. Less congested and less susceptible to interference than 2.4 GHz.
  • Keep the router central and elevated. Don't bury it behind a generator or under a table.
  • Use a simple SSID and password. You'll be telling people what they are all day. Something like FieldDay with a short password works.
  • Bring a spare ethernet cable. If Wi-Fi gets flaky, plugging a laptop directly into the router keeps that station running.

Test It First

Set everything up at home before Field Day and make sure it works:

1 Power on the router and server. Wait for FD Commander to start.

2 Connect a phone or laptop to the Wi-Fi.

3 Open a browser and go to the server's address. You should see the login page.

4 Try a second device. Log a test contact from each and make sure they both see it.

Watch out

If you're using a Raspberry Pi, make sure it has a reliable power supply. A Pi that brown-outs under load will corrupt its SD card and take your server down mid-event.

Quick Reference

Fill this in before you leave the house and bring it to the site:

Router SSID: _______________

Wi-Fi Password: _______________

Server IP: _______________

Router Admin: _______________