Port 8443: HTTPS alternate
TCP 8443 is the port for Alternate HTTPS (admin panels, Tomcat, UniFi, Plesk). Restrict admin panels to known IPs.
| Service | Alternate HTTPS (admin panels, Tomcat, UniFi, Plesk) |
|---|---|
| Protocol | TCP |
| Exposure risk | Medium: expose with care |
| Range | Registered (1024–49151) |
What port 8443 does
The alternate HTTPS port used by Tomcat, UniFi Network controllers, Plesk and many appliance admin interfaces.
Should port 8443 be open?
Restrict admin panels to known IPs.
Find what's listening on port 8443
- Linux:
sudo ss -tulpn | grep :8443 - macOS:
sudo lsof -nP -i :8443 - Windows:
netstat -ano | findstr :8443, then look up the PID in Task Manager.
Open or block it in a firewall
- ufw:
sudo ufw allow 8443/tcp(ordeny) - firewalld:
sudo firewall-cmd --add-port=8443/tcp --permanent && sudo firewall-cmd --reload - Windows:
New-NetFirewallRule -DisplayName "Port 8443" -Direction Inbound -Protocol TCP -LocalPort 8443 -Action Allow
Port assignment per the IANA Service Name and Transport Protocol Port Number Registry. Test several ports at once with the port scanner, or any port with the open port checker.
Questions about port 8443
What is port 8443 used for?
Alternate HTTPS (admin panels, Tomcat, UniFi, Plesk). The alternate HTTPS port used by Tomcat, UniFi Network controllers, Plesk and many appliance admin interfaces.
Is port 8443 TCP or UDP?
TCP. HTTPS alternate uses TCP port 8443.
Is it safe to open port 8443?
Medium: expose with care. Restrict admin panels to known IPs.
How do I check if port 8443 is open?
Use the checker on this page: it connects to your host on TCP 8443 from the internet. Locally, run
nc -vz host 8443 (macOS/Linux) or Test-NetConnection host -Port 8443 (PowerShell). To see what is listening on your own machine, run ss -tulpn | grep :8443 (Linux) or netstat -ano | findstr :8443 (Windows).