Port 174
mailq · TCP/UDP
| Range | System/well-known port (0–1023) |
|---|---|
| Protocol | TCP/UDP |
| Service | mailq |
Frequently asked questions
What is port 174 used for?
Port 174 is registered with the IANA for mailq (TCP/UDP). Description: MAILQ.
Is port 174 a well-known port?
Yes. Port 174 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 174 is open?
Locally on Linux with ss -tulpn | grep ':174\b', on Windows with netstat -ano | findstr :174. To test a remote host use Test-NetConnection <host> -Port 174 in PowerShell or nc -zv <host> 174 on Linux/macOS.
How do I open port 174 in the firewall?
Ubuntu/Debian (ufw): sudo ufw allow 174/tcp. Fedora/RHEL (firewalld): sudo firewall-cmd --add-port=174/tcp --permanent, then firewall-cmd --reload. Windows (PowerShell as administrator): New-NetFirewallRule -DisplayName "Port 174" -Direction Inbound -Protocol TCP -LocalPort 174 -Action Allow.
IANA registry entries
| Protocol | Service | Description (IANA) |
|---|---|---|
| TCP | mailq | MAILQ |
| UDP | mailq | MAILQ |