Port 3399
csms · TCP/UDP
| Range | Registered port (1024–49151) |
|---|---|
| Protocol | TCP/UDP |
| Service | csms |
Frequently asked questions
What is port 3399 used for?
Port 3399 is registered with the IANA for csms (TCP/UDP). Description: CSMS.
Is port 3399 a well-known port?
No. Port 3399 is in the range 1024–49151 (registered or user ports). Ordinary programs may open it without root privileges.
How do I check whether port 3399 is open?
Locally on Linux with ss -tulpn | grep ':3399\b', on Windows with netstat -ano | findstr :3399. To test a remote host use Test-NetConnection <host> -Port 3399 in PowerShell or nc -zv <host> 3399 on Linux/macOS.
How do I open port 3399 in the firewall?
Ubuntu/Debian (ufw): sudo ufw allow 3399/tcp. Fedora/RHEL (firewalld): sudo firewall-cmd --add-port=3399/tcp --permanent, then firewall-cmd --reload. Windows (PowerShell as administrator): New-NetFirewallRule -DisplayName "Port 3399" -Direction Inbound -Protocol TCP -LocalPort 3399 -Action Allow.
IANA registry entries
| Protocol | Service | Description (IANA) |
|---|---|---|
| TCP | csms | CSMS |
| UDP | csms | CSMS |