Port 451
sfs-smp-net · TCP/UDP
| Range | System/well-known port (0–1023) |
|---|---|
| Protocol | TCP/UDP |
| Service | sfs-smp-net |
Frequently asked questions
What is port 451 used for?
Port 451 is registered with the IANA for sfs-smp-net (TCP/UDP). Description: Cray Network Semaphore server.
Is port 451 a well-known port?
Yes. Port 451 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 451 is open?
Locally on Linux with ss -tulpn | grep ':451\b', on Windows with netstat -ano | findstr :451. To test a remote host use Test-NetConnection <host> -Port 451 in PowerShell or nc -zv <host> 451 on Linux/macOS.
How do I open port 451 in the firewall?
Ubuntu/Debian (ufw): sudo ufw allow 451/tcp. Fedora/RHEL (firewalld): sudo firewall-cmd --add-port=451/tcp --permanent, then firewall-cmd --reload. Windows (PowerShell as administrator): New-NetFirewallRule -DisplayName "Port 451" -Direction Inbound -Protocol TCP -LocalPort 451 -Action Allow.
IANA registry entries
| Protocol | Service | Description (IANA) |
|---|---|---|
| TCP | sfs-smp-net | Cray Network Semaphore server |
| UDP | sfs-smp-net | Cray Network Semaphore server |