Issue Cannot access to server suddenly

[BenPT]

Cannot access to Pleask server over http or https suddenly while all sites hosted in it was working properly.

This server was working properly previously and is first time suddenly can't be reached without touch anything on the server before it happened.

In Chrome:
https://server1.domain.com refused to connect

In Firefox:
Unable to connect

In Edge:
Hmmm... cannot reach this page

In IE
Cannot reach this page

In Opera
This site can’t be reached

• Opera auto redirected this server from https://server1.domain.com to server1.domain.com

 

[IgorG]

What about port 8443? Correct URL for Plesk interface is https://domain.tls:8443
Additionally, make sure that hostname server1.domain.com is still resolvable to correct IP address.

 

[Bitpalast]

Most likely the firewall (iptables) have blocked your local IPv4 address. Verify that you are not using any false email login data. Most frequently users have email clients active that auto-login every n seconds. When such clients use wrong credentials, the fail2ban service will block the source IP (your local IP). Hence you can no longer access your own system. The quick solution to be able to access your server again is to restart your DSL router, normally this will give you a new DSL IP, but in the long run you must identify the root cause, which is normally wrong logins.

 

[hdelaisse]

I've got same problem
Home > Tools & Settings > IP Address Banning
look in the Banned IP Addresses
If you have a fixed IP where you work on your PLESK select you IP in the list and move to Trusted IPs