Error undefined function mysqli_connect on Cron Job

General
1

I have a problem executing a Cronjob with Virtualmin and Nginx. I have to execute a php script. When I execute it with cronjob I have this error:

PHP Fatal error:  Uncaught Error: Call to undefined function mysqli_connect() in /home/ivirgin/public_html/check.php:36
Stack trace:
#0 {main}
  thrown in /home/ivirgin/public_html/check.php on line 36

Fatal error: Uncaught Error: Call to undefined function mysqli_connect() in /home/ivirgin/public_html/check.php:36
Stack trace:
#0 {main}
  thrown in /home/ivirgin/public_html/check.php on line 36

While, if I execute the script without cronjob but writing address on browser, I have not errors.

This is the command that I inserted in Cronjob:

php -f /home/ivirgin/public_html/check.php

Can anyone help me to solve it? Thanks!

2

The issue you’re facing is due to the PHP CLI (Command Line Interface) not having the mysqli extension enabled, even though the web server’s PHP (likely FPM or mod-php with Nginx) does.

Why it works in the browser but not in Cron

  • Browser: Uses the PHP version configured with the web server, which likely has mysqli enabled.
  • Cron: Uses the system PHP CLI version, which may not have mysqli compiled or enabled.

Solution

Step 1: Check which PHP version is used in cron

In the cron job, run this first to see which PHP CLI is being used:

which php

Or inside your script, temporarily add:

<?php
echo shell_exec('which php');
?>

This might show something like /usr/bin/php, which might not be the same PHP version used by Nginx.

Step 2: Verify if mysqli is available in that version

Run:

php -m | grep mysqli

If nothing shows up, the CLI PHP does not have mysqli enabled.

Step 3: Fix options

Here are a few ways to solve this:

Option 1: Use full path to the correct PHP binary

If your web server uses a different PHP version (e.g., /opt/rh/php81/root/usr/bin/php), use that explicitly:

/opt/rh/php81/root/usr/bin/php -f /home/ivirgin/public_html/check.php

You can find it with:

whereis php

Or check what PHP binary is used by Virtualmin for that domain under: Virtualmin → Server Configuration → PHP Versions

Option 2: Switch cron’s PHP version (optional)

If you’re on a system with multiple PHP versions (e.g., with update-alternatives), you can configure which PHP is used globally by CLI:

sudo update-alternatives --config php

Then pick the one with mysqli enabled.

Option 3: Use a wrapper script with environment variables (if needed)

If you’re using PHP with custom environment settings (e.g., with SCL on CentOS or Ubuntu modules), you might need a wrapper script like:

#!/bin/bash
source /opt/rh/php81/enable
php -f /home/ivirgin/public_html/check.php

Save it as /home/ivirgin/run_check.sh, make it executable:

chmod +x /home/ivirgin/run_check.sh

Then put this in your cron job:

/home/ivirgin/run_check.sh