Port 3333
dec-notes · TCP/UDP
| Range | Registered port (1024–49151) |
|---|---|
| Protocol | TCP/UDP |
| Service | dec-notes |
Frequently asked questions
What is port 3333 used for?
Port 3333 is registered with the IANA for dec-notes (TCP/UDP). Description: DEC Notes.
Is port 3333 a well-known port?
No. Port 3333 is in the range 1024–49151 (registered or user ports). Ordinary programs may open it without root privileges.
How do I check whether port 3333 is open?
Locally on Linux with ss -tulpn | grep ':3333\b', on Windows with netstat -ano | findstr :3333. To test a remote host use Test-NetConnection <host> -Port 3333 in PowerShell or nc -zv <host> 3333 on Linux/macOS.
How do I open port 3333 in the firewall?
Ubuntu/Debian (ufw): sudo ufw allow 3333/tcp. Fedora/RHEL (firewalld): sudo firewall-cmd --add-port=3333/tcp --permanent, then firewall-cmd --reload. Windows (PowerShell as administrator): New-NetFirewallRule -DisplayName "Port 3333" -Direction Inbound -Protocol TCP -LocalPort 3333 -Action Allow.
IANA registry entries
| Protocol | Service | Description (IANA) |
|---|---|---|
| TCP | dec-notes | DEC Notes |
| UDP | dec-notes | DEC Notes |