Connecting your phone to 9t

First make the server address load in the phone's browser. Then configure the Android app with the same reachable address. This separates server/network problems from pairing and background-receiver problems.

Examples use port 3265. Replace it everywhere if you selected another port.

Choose the address

localhost and 127.0.0.1 refer to the device opening the address. On your phone, they mean the phone. 0.0.0.0 is a server listener setting, not a destination.

For a normal LAN installation, .env.production should contain:

NINE_T_HOST=0.0.0.0
PORT=3265
NINE_T_HTTPS=false

Restart 9t after changes. Do not start a second copy on the same port.

Windows with Ubuntu in WSL 2

WSL 2 normally uses a virtual network. Reaching its address from Windows does not establish that a phone can reach it. Forward the Windows port into Ubuntu, then connect the phone to Windows' LAN address.

1. Check that 9t is running in Ubuntu

curl -fsS http://127.0.0.1:3265/api/status
ss -ltnp 'sport = :3265'
hostname -I

A completed installation returns {"initialized":true}. The listener should show 0.0.0.0:3265.

2. Forward the port in Windows

Open Windows PowerShell as Administrator:

$distro = "Ubuntu"
$port = 3265
wsl -d $distro hostname -I

Copy Ubuntu's IPv4 address into $wslIp below, then add the rule:

$wslIp = "172.22.200.10" # Replace with YOUR Ubuntu IPv4 address
netsh interface portproxy add v4tov4 listenaddress=0.0.0.0 listenport=$port connectaddress=$wslIp connectport=$port
netsh interface portproxy show all

3. Allow the local connection through Windows Firewall

Still in Administrator PowerShell, once per selected port:

New-NetFirewallRule -Name "9t-LAN-$port" -DisplayName "9t LAN TCP $port" -Direction Inbound -Action Allow -Protocol TCP -LocalPort $port -RemoteAddress LocalSubnet -Profile Any

Do not disable Windows Firewall to troubleshoot.

4. Find the address for the phone

In Windows PowerShell, run ipconfig:

• Laptop joined the phone's hotspot: use the Windows Wi-Fi adapter IPv4 address.
• Phone joined the laptop's hotspot: use the Windows adapter serving that hotspot (often Local Area Connection*).
• Both joined a router: use the laptop's active Wi-Fi or Ethernet IPv4 address.

Then open http://<that-ip>:3265 on the phone and sign in.

After restarting or changing networks

Recheck Ubuntu's address after a WSL restart. If it changed, update only the existing forwarding rule:

netsh interface portproxy set v4tov4 listenaddress=0.0.0.0 listenport=$port connectaddress=$wslIp connectport=$port

If Windows' Wi-Fi/hotspot IP changed, update the app's LAN URL too.

Pair the Android app

1. Open the reachable server in a browser and sign in.
2. Open Settings → Android devices & pairing (/devices) and create a phone pairing code.
3. Enter the code in the app. Under Connect, enter the reachable server address as its LAN URL.
4. Choose LAN-only for an isolated local test, or Automatic for LAN-first with public fallback.
5. Send a small file and a new snippet to check receiving.

Troubleshoot in order