[nagios server]/nagvis/frontend/nagvis-js/index.php drop error 500 after login

[MartonT888]

Hello All,

I installed the NagVis for our Nagios Core server. All the prerequisites has been installed and when I try to log in on the given Nagvis site.
I got an error 500. So the authentication with admin/admin works fine and after the things go wrong.
Do you have any hint or idea for this problem?

PHP Version 5.4.16
Nagios® Core™ 4.4.7
Red Hat Enterprise Linux Server 7.6 (Maipo)
Apache/2.4.6 (Red Hat Enterprise Linux)

Same behavior with all browser .

Httpd logs:
[Thu Feb 02 10:29:37.975026 2023] [:error] [pid 68612] [client 10.75.131.228:49658] PHP Fatal error: Class 'PDO' not found in /usr/local/nagvis/share/server/core/classes/CorePDOHandler.php on line 273
[Thu Feb 02 10:29:41.240288 2023] [autoindex:error] [pid 68611] [client 10.75.131.228:49657] AH01276: Cannot serve directory /var/www/html/: No matching DirectoryIndex (index.html,index.php) found, and server-generated directory index fo
rbidden by Options directive
[Thu Feb 02 10:29:52.086505 2023] [:error] [pid 68614] [client 10.75.131.228:49690] PHP Fatal error: Class 'PDO' not found in /usr/local/nagvis/share/server/core/classes/CorePDOHandler.php on line 273
[Thu Feb 02 10:36:06.084358 2023] [autoindex:error] [pid 68829] [client 10.75.131.228:50049] AH01276: Cannot serve directory /var/www/html/: No matching DirectoryIndex (index.html,index.php) found, and server-generated directory index fo
rbidden by Options directive
[Thu Feb 02 10:36:15.609444 2023] [:error] [pid 68612] [client 10.75.131.228:50050] PHP Fatal error: Class 'PDO' not found in /usr/local/nagvis/share/server/core/classes/CorePDOHandler.php on line 273
[Thu Feb 02 10:36:17.862383 2023] [:error] [pid 68874] [client 10.75.131.228:50068] PHP Fatal error: Class 'PDO' not found in /usr/local/nagvis/share/server/core/classes/CorePDOHandler.php on line 273
[Thu Feb 02 10:36:18.450382 2023] [:error] [pid 68611] [client 10.75.131.228:50067] PHP Fatal error: Class 'PDO' not found in /usr/local/nagvis/share/server/core/classes/CorePDOHandler.php on line 273

[miken32]

The error PHP Fatal error: Class 'PDO' not found is quite clear. Install PDO support on your server.