Port 903
ideafarm-panic · TCP/UDP
| Range | System/well-known port (0–1023) |
|---|---|
| Protocol | TCP/UDP |
| Service | ideafarm-panic |
Frequently asked questions
What is port 903 used for?
Port 903 is registered with the IANA for ideafarm-panic (TCP/UDP). Description: self documenting Telnet Panic Door; self documenting Panic Door: send 0x00 for info.
Is port 903 a well-known port?
Yes. Port 903 is in the range 0–1023 (system or well-known ports). On Linux and macOS only privileged processes may bind to these ports.
How do I check whether port 903 is open?
Locally on Linux with ss -tulpn | grep ':903\b', on Windows with netstat -ano | findstr :903. To test a remote host use Test-NetConnection <host> -Port 903 in PowerShell or nc -zv <host> 903 on Linux/macOS.
How do I open port 903 in the firewall?
Ubuntu/Debian (ufw): sudo ufw allow 903/tcp. Fedora/RHEL (firewalld): sudo firewall-cmd --add-port=903/tcp --permanent, then firewall-cmd --reload. Windows (PowerShell as administrator): New-NetFirewallRule -DisplayName "Port 903" -Direction Inbound -Protocol TCP -LocalPort 903 -Action Allow.
IANA registry entries
| Protocol | Service | Description (IANA) |
|---|---|---|
| TCP | ideafarm-panic | self documenting Telnet Panic Door |
| UDP | ideafarm-panic | self documenting Panic Door: send 0x00 for info |