Unable to access the GUI - HTTP ERROR 500

[moxpearl]

Hey Team

Bit of a odd one here, everything has been running fine, until either a OS update or Reboot (CentoS and Zabbix 4.4)

However now I am unable to access the GUI as I am getting HTTP ERROR 500 (Have tried Multiple Browsers, and all the same)

Now the odd thing is, the server itself seems to be running fine.. still sending out alerts as far as I can tell (Eg when I tried to reboot the server I got the alert that the Zabbix server was rebooted)

I cant see anything abnormal in the zabbix_agentd.log or zabbix_server.log files.. (Debug Level 3) so a little out of ideas.

If anyone has any ideas then that would be great

Cheers

EDIT: - Looks like something was using the port of apache (nginx).. stopped the service and started apache fine. Now getting a ERR_CONNECTION_REFUSED
EDIT2: Rebooted and back to the original error.. hmmm

[tim.mooney]

The web interface is separate from zabbix-server, so the server can start and run even when there are problems with the web interface.

Web problems generally wouldn't be logged to zabbix_server.log and definitely not to zabbix_agentd.log. They would instead be in your web server's log files. Probably /var/log/httpd/error_log or such.

If it was from an update, you probably need to look in /etc/httpd/conf.d and (if the CentOS version is recent enough) /etc/httpd/conf.modules.d/ , at least for Apache httpd. If packages were updated, they may have dropped stock copies of config files into place if you had previously completely removed a stock config file.

If you're running PHP as a separate process via PHP-FPM, you may also need to verify that it's starting up and not logging any errors.

[moxpearl]

Just an Update.. fixed this.

Did a complete uninstall and reinstall of Apache... from what I could see it was *something* with Apache Config following an update.