Port 69: TFTP
UDP 69 is the port for Trivial File Transfer Protocol. Never on the internet; anyone could read or overwrite files.
| Service | Trivial File Transfer Protocol |
|---|---|
| Protocol | UDP |
| Exposure risk | High: do not expose to the internet |
| Range | Well-known (0–1023): binding needs root/admin on Unix |
Port 69 is UDP-only. UDP has no handshake, so no online checker can reliably tell open from filtered; test with the service's own client.
What port 69 does
TFTP is a minimal file transfer protocol with no authentication, used for PXE network booting, and for pushing firmware and configs to switches, phones and routers.
Should port 69 be open?
Never on the internet; anyone could read or overwrite files.
Find what's listening on port 69
- Linux:
sudo ss -tulpn | grep :69 - macOS:
sudo lsof -nP -i :69 - Windows:
netstat -ano | findstr :69, then look up the PID in Task Manager.
Open or block it in a firewall
- ufw:
sudo ufw allow 69/udp(ordeny) - firewalld:
sudo firewall-cmd --add-port=69/udp --permanent && sudo firewall-cmd --reload - Windows:
New-NetFirewallRule -DisplayName "Port 69" -Direction Inbound -Protocol UDP -LocalPort 69 -Action Allow
Port assignment per the IANA Service Name and Transport Protocol Port Number Registry. Test several ports at once with the port scanner, or any port with the open port checker.
Questions about port 69
What is port 69 used for?
Trivial File Transfer Protocol. TFTP is a minimal file transfer protocol with no authentication, used for PXE network booting, and for pushing firmware and configs to switches, phones and routers.
Is port 69 TCP or UDP?
UDP. TFTP uses UDP port 69.
Is it safe to open port 69?
High: do not expose to the internet. Never on the internet; anyone could read or overwrite files.
How do I check if port 69 is open?
Port 69 is UDP-only, which has no handshake, so an online TCP checker can't confirm it. Use the service's own client to test, and check what is listening locally with
ss -ulpn | grep :69 (Linux) or netstat -ano | findstr :69 (Windows).