Port 5353
mdns · TCP/UDP
| Range | Registered port (1024–49151) |
|---|---|
| Protocol | TCP/UDP |
| Service | mdns |
| Reference | RFC 6762 |
Frequently asked questions
What is port 5353 used for?
Port 5353 is registered with the IANA for mdns (TCP/UDP). Description: Multicast DNS.
Is port 5353 a well-known port?
No. Port 5353 is in the range 1024–49151 (registered or user ports). Ordinary programs may open it without root privileges.
How do I check whether port 5353 is open?
Locally on Linux with ss -tulpn | grep ':5353\b', on Windows with netstat -ano | findstr :5353. To test a remote host use Test-NetConnection <host> -Port 5353 in PowerShell or nc -zv <host> 5353 on Linux/macOS.
How do I open port 5353 in the firewall?
Ubuntu/Debian (ufw): sudo ufw allow 5353/tcp. Fedora/RHEL (firewalld): sudo firewall-cmd --add-port=5353/tcp --permanent, then firewall-cmd --reload. Windows (PowerShell as administrator): New-NetFirewallRule -DisplayName "Port 5353" -Direction Inbound -Protocol TCP -LocalPort 5353 -Action Allow.
IANA registry entries
| Protocol | Service | Description (IANA) |
|---|---|---|
| TCP | mdns | Multicast DNS |
| UDP | mdns | Multicast DNS |