After ZBXNEXT-8698(subissue #30) implementation there might be confusing situation about real status of Active node (server). We should treat Frontend TLS configure same way as TCP connection with incorrect PORT or IP.

Precondition:

• Setup two HA nodes. Example => https://confluence.zabbix.lan/pages/viewpage.action?spaceKey=QA&title=High+availability+node+configuration
• Setup TLS for FE and both Servers
• FE is located with main node
• Add two parameters in ui/conf/zabbix.conf.php. Use IP and Port of remote node. E.g.

  $ZBX_SERVER            = '{your_IP}';
  $ZBX_SERVER_PORT        = '10075';
  

Steps to reproduce:

• Start server for remote node
• Start server with main node
• Check system information (Looks good at this step)
  
  Case 1
• Change port in ui/conf/zabbix.conf.php => $ZBX_SERVER_PORT='0';
• Check system information page
  Case 2
• Change port in ui conf => $ZBX_SERVER_PORT= '10075'; Add invalid TLS key or certificate in ui/conf/zabbix.conf.php so there will be TLS connection error.
• Check system information page

Result:
Case 1 => Frontend is trying to connect with incorrect Port at the same time we see that HA node is in Active state, server is running. Warning message "Zabbix server is not running: the information displayed may not be current." appears.

Case 2
Frontend is trying to connect with incorrect TLS key/cert file at the same time we see that HA node changed status to Unavailable (implemented in subissue #30), server is running. Warning message "Unable to connect to the Zabbix server due to TLS settings. Some functions are unavailable." appears.

Expected: We shouldn't change HA node status from Active to Unavailable. HA node Active status could be reused for "Zabbix server is not running" value.

Suggestion: For case 1 would be nice to change warning message e.g. "Unable to connect to the Zabbix server" or "Connection to Zabbix server refused" and use "Zabbix server is not running" => "Yes" value.

For case 2 use "Zabbix server is not running" => "Yes" value and Node status => Active. Warning message should stay unchanged => "Unable to connect to the Zabbix server due to TLS settings. Some functions are unavailable."