Port 404
nced · TCP/UDP
| Range | System/well-known port (0–1023) |
|---|---|
| Protocol | TCP/UDP |
| Service | nced |
Frequently asked questions
What is port 404 used for?
Port 404 is registered with the IANA for nced (TCP/UDP). Description: nced.
Is port 404 a well-known port?
Yes. Port 404 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 404 is open?
Locally on Linux with ss -tulpn | grep ':404\b', on Windows with netstat -ano | findstr :404. To test a remote host use Test-NetConnection <host> -Port 404 in PowerShell or nc -zv <host> 404 on Linux/macOS.
How do I open port 404 in the firewall?
Ubuntu/Debian (ufw): sudo ufw allow 404/tcp. Fedora/RHEL (firewalld): sudo firewall-cmd --add-port=404/tcp --permanent, then firewall-cmd --reload. Windows (PowerShell as administrator): New-NetFirewallRule -DisplayName "Port 404" -Direction Inbound -Protocol TCP -LocalPort 404 -Action Allow.
IANA registry entries
| Protocol | Service | Description (IANA) |
|---|---|---|
| TCP | nced | nced |
| UDP | nced | nced |