Port 8443 — HTTPS alternate

Security guidance

Same advice as 8080 — identify the service and restrict access if it is administrative.

Test port 8443 yourself

From your own machine, against any host (swap in your domain):

macOS / Linux — netcat

nc -vz example.com 8443

Any OS — nmap

nmap -p 8443 example.com

Windows — PowerShell

Test-NetConnection example.com -Port 8443

open = a service answered on port 8443; closed = the host replied but nothing is listening; filtered = a firewall silently dropped the probe. These test from your network — our port checker tests from the outside, the view that matters for security.

Other common ports