How to secure Plesk hostname on port 8443 with SSL certificate
Today in this document I will show you how to protect plesk panel from unauthorized access. Here we use SSL certificate on plesk hostname on port 8443 at panel login.
Now we discuss the steps for protect the plesk panel for unauthorized access:
Step 1. Enable Let’s encrypt extension installed
Step 2. Tools & Settings > SSL/TLS Certificates & Open SSL/TLS certificate

step 3. After selecting or installing Let’s encrypt extension

Step 4. Now we are ready to select SSL/TLS certificate go to Tools & Settings > SSL/TLS Certificates

step 5. Then choose Let’s encrypt certificate for further
step 6. After this type your domain name and email address

Conclusion:
All steps are done you can check by type https://domain_name:8443