HTTP error 500 - This page isn't working at the moment

[gwangjong]

Hi Guys,

I've encountered this kind of error, what seems to be the problem? thank youuuuu guys.

[MRedbourne]

We're going to need a little bit more information. A generic screenshot of a 500 internal server error isn't very helpful, aside from telling us it's likely some kind of http issue.

Questions
What OS Distro, major, minor version are you using? (Eg: Red Hat Enterprise Linux, 9.2)
What version of Zabbix are you running?
What Web Front End are you running? (Apache, Nginx, etc)
Any error messages in locations like /var/log/nginx, /usr/local/apache/logs (or other locations you may log too)?
Are you using app armour, SE Linux, or similar? If so, is there anything in those logs? (SE Linux: ausearch -m avc -ts recent)
Have you checked your file permissions to make sure Zabbix/www-data can access the web file locations?

Edit:
Also, what shows in /var/log/zabbix/*.log? Can you post your logs for us to look at?

[gwangjong]

Hello Sir,

I've been using Cent OS 7,version of zabbix is 5.0TLS, for the web front end is Apache.

I can't seem to find the location of /usr/local/apache/logs


Apologies, I'm not sure on how to check the file permissions regarding Zabbix/www-data.

For the /var/log/zabbix/*.log

what should I select from those items?

Thank you..

[MRedbourne]

OK, just some quick notes:

Zabbix 5.0 LTS is no longer fully supported (EOFS: May 31, 2023, EOLS: May 31, 2025). CentOS 7 (I'm assuming 7.9) is EOL in 2024. You may want to consider patching the environment and upgrading your server. Was this installation previously running? If so, when did you notice a change in the behaviour? Did anything precede that change in behaviour (eg: yum -y update, changed the config files)?

Apache logs to /var/log/httpd/* for RHEL/CentOS. There should be a file in there called error_log (and possibly error_log-<date>). This is what one of my nodes looks like (RHEL 9.2, Apache, Zabbix 6.0 LTS). I'm specifically interesting in the error logs as they may indicate why the httpd service is returning a generic internal error.



Regarding the file permissions, that was mostly aimed at ensuring the web server files have the correct owner(s).

If you run these commands and post the results

ls -la /etc/zabbix/web
ls -la /etc/httpd
ls -la /etc/httpd/conf
systemctl status httpd
systemctl status zabbix-server
ausearch -m avc -ts recent

If you post /var/log/zabbix/zabbix_server.log, make sure to sanitize any sensitive data from it first (like hostnames).

[gwangjong]

Hello Sir, Good day!

Actually, I'm new to this kind of environment, and I recently started this project a week ago. Currently the only available OS I have is CentOs 7, would it be much better to start with the Zabbix 6.4, CentOS 9 Stream? :O

Here's the screenshots

ausearch -m avc -ts recent - it says <no matches>





Thank you for your prompt response.

[MRedbourne]

Re: available OS and Zabbix Software. If you're just starting this project (Eg: It's not a pre-existing tool already in use), I'd highly recommend using the latest LTS version of Zabbix (6.0 LTS) or simply the latest version of Zabbix (6.4). Which one you decide is up to you. At the minute, my infrastructure is on 6.0.22, though we'll be upgrading to 6.4.8 to take advantage of some new features we need. You can use CentOS 9 Stream if you wish. We stay away from CentOS Stream (devel branch of Red Hat with no official support), but that's a decision for you to make.

For what it's worth, Dmitry Lambert, a former (Senior) Support Engineer, Solution Architect, and now Head of Customer Support at Zabbix has a detailed guide on installing Zabbix 6.0 LTS on YouTube: How To Install Zabbix 6.0 LTS - YouTube. It's a very comprehensive guide that I would highly recommend watching.

Regardless: Concerning the problem at hand.

I would recommend removing zabbix.conf.ph: "rm /etc/zabbix/web/zabbix.conf.ph". It shouldn't impact anything (it's an empty file), but it shouldn't be there. Your file permission look OK. The return result of the ausearch command is good as well. Can you post your error logs? They should be here: /var/log/httpd/error_log*.

When you connect to the web page, how do you connect to it?

- https://10.105.0.43
- https://10.105.0.43/zabbix/
- http://10.105.0.43
- http://10.105.0.43/zabbix/

Or something else?

[gwangjong]

Hello Sir, Good day again!

Thank you for the recommendation, I'll explore also the latest version of Zabbix. I'll definitely watch the comprehensive guide.

This came from the error_log



When connecting to the webpage, I'm using https://10.105.0.43/zabbix/

thank you for usual support!

[MRedbourne]

Hey mate,

OK. Let's fix the time zone in Apache. As it indicates, "Philippines" is not a valid time zone on RHEL/CentOS systems. You share a time zone with Western AU, China, Taiwan, and a few others. I'd suggest you set your time zone to "Asia/Shanghai" or similar UTC+8 locations. Interesting though that there isn't anything in the last day or two.

Can you S/FTP these files off your server and upload them here? Obfuscate your DBs, Server, Usernames, Passwords, etc:

/etc/zabbix/web/*
/etc/httpd/conf/httpd.conf
/etc/httpd/conf.d/*.conf
/var/log/httpd/error_*
/var/log/httpd/ssl_error*
/var/log/php-fpm/*

Which version of PHP are you running? (Run: rpm -qa | grep -i "php")

[gwangjong]

Hello Sir,

Good day!
I changed the timezone from Asia/Philippines to Asia/Manila

Finally, I was able to Login.


Thank you for your usual support!

[MRedbourne]

G'Day Mate,

Excellent news. Glad I could be of assistance. If you run into any other issues I'd advise opening a new thread describing your issue and environment information. Please follow this guide for any subsequent issues. It can help volunteers (or Zabbix staff) expedite resolving your issues.