Port 8443 — HTTPS-Alt (TCP)
What is Port 8443?
Port web selamat alternatif.
This is a registered port (1024–49151) often assigned to vendor or application services like HTTPS-Alt. · No dedicated RFC; follows HTTPS (RFC 9110, RFC 8446)
When do you need Port 8443 open?
Open when an HTTPS service runs on a non-standard port — for example Tomcat with TLS or Jenkins HTTPS. Often used in development environments or when port 443 is already occupied by another service.
Common uses and software
- Apache Tomcat HTTPS
- Jenkins HTTPS
- Plesk control panel
- cPanel/WHM
- Kubernetes API (alternate)
- VMware vSphere
Security
Apply the same TLS security standards as port 443: valid certificate, TLS 1.2 minimum, strong cipher suites, and HSTS headers. Services on port 8443 are often admin interfaces — restrict access to known management IPs. Keep the underlying server software updated and apply security patches promptly.
Is Port 8443 safe?
An open port increases your attack surface. Safety depends on how HTTPS-Alt is configured.
Low risk, but confirm that HTTPS-Alt on this port is intentionally running and required by your application before leaving it open.
Test connectivity for Port 8443 on any host.
How to Open Port 8443
To allow incoming connections to Port 8443 (HTTPS-Alt) from outside your network, configure your firewall and add a port forwarding rule on your router pointing to your device's local IP address.
Open Windows Defender Firewall → Advanced Settings → Inbound Rules → New Rule → Port → TCP → Specific local ports: 8443 → Allow the connection → Name and save the rule.
netsh advfirewall firewall add rule name="Open Port 8443" dir=in action=allow protocol=tcp localport=8443sudo ufw allow 8443/tcpsudo iptables -A INPUT -p tcp --dport 8443 -j ACCEPTLog into your router (192.168.1.1 or 192.168.0.1) → Port Forwarding → Add a new rule: Protocol TCP, External port 8443, Internal IP: your device's local IP, Internal port 8443 → Save.
How to close Port 8443
If you do not need HTTPS-Alt, block this port in your firewall or router.
To block port 8443 on Windows, run the following command in PowerShell or Command Prompt (as Administrator):
netsh advfirewall firewall add rule name="Block Port 8443" dir=in action=block protocol=tcp localport=8443sudo ufw deny 8443/tcpsudo iptables -A INPUT -p tcp --dport 8443 -j DROPRemove or disable any port forwarding rule for Port 8443.
Frequently Asked Questions
What is Port 8443 used for?▾
Port 8443 is the default TCP port for HTTPS-Alt. It is used by servers and applications that need to accept incoming connections for this service. Whether you need it open depends on whether you are actively running a HTTPS-Alt server — if not, it should remain closed to reduce your attack surface.
Is Port 8443 safe to keep open?▾
An open Port 8443 increases your attack surface. If you are not actively running HTTPS-Alt, close this port in your firewall and remove any port forwarding rules. If HTTPS-Alt must be accessible, restrict access to known IP ranges, keep the service software updated with security patches, and use strong authentication.