Port 4991
vrt · TCP/UDP
| Range | Registered port (1024–49151) |
|---|---|
| Protocol | TCP/UDP |
| Service | vrt |
| Registered | 2009-01-08 |
Frequently asked questions
What is port 4991 used for?
Port 4991 is registered with the IANA for vrt (TCP/UDP). Description: VITA Radio Transport.
Is port 4991 a well-known port?
No. Port 4991 is in the range 1024–49151 (registered or user ports). Ordinary programs may open it without root privileges.
How do I check whether port 4991 is open?
Locally on Linux with ss -tulpn | grep ':4991\b', on Windows with netstat -ano | findstr :4991. To test a remote host use Test-NetConnection <host> -Port 4991 in PowerShell or nc -zv <host> 4991 on Linux/macOS.
How do I open port 4991 in the firewall?
Ubuntu/Debian (ufw): sudo ufw allow 4991/tcp. Fedora/RHEL (firewalld): sudo firewall-cmd --add-port=4991/tcp --permanent, then firewall-cmd --reload. Windows (PowerShell as administrator): New-NetFirewallRule -DisplayName "Port 4991" -Direction Inbound -Protocol TCP -LocalPort 4991 -Action Allow.
IANA registry entries
| Protocol | Service | Description (IANA) |
|---|---|---|
| TCP | vrt | VITA Radio Transport |
| UDP | vrt | VITA Radio Transport |