When scheduling tasks that need to execute based on client timezones rather than server time, many developers encounter the same issue you're facing. The CRON_TZ variable is often misunderstood in its implementation.

The problem in your example stems from a common misconception about how CRON_TZ operates:

32 16 08 05 * /usr/bin/curl CRON_TZ=Africa/Algiers https://www.example.com/SendCron.php?CronID=382

The CRON_TZ variable must be set before the cron time specification, not as part of the command. The cron daemon reads this variable when parsing the schedule, not when executing the command.

Here are three proper ways to handle timezones in cron jobs:

Method 1: Environment Variable in Crontab

CRON_TZ=Africa/Algiers
32 16 08 05 * /usr/bin/curl https://www.example.com/SendCron.php?CronID=382

Method 2: Per-Job Specification

32 16 08 05 * export CRON_TZ=Africa/Algiers; /usr/bin/curl https://www.example.com/SendCron.php?CronID=382

Method 3: Timezone Conversion in Script

For more complex scenarios, handle timezone conversion within your PHP script:

date_default_timezone_set('Africa/Algiers');
// Your email sending logic here

Remember that:

• Not all cron implementations support CRON_TZ (check your version)
• CPanel might have additional restrictions or requirements
• The server's system time still affects process execution and logging

If you're using CPanel, consider these options:

1. Use CPanel's "Advanced Cron Style" with timezone selector
2. Configure server timezone to match your client requirements
3. Use a dedicated scheduling service like AWS CloudWatch Events

Always verify your cron jobs with a test script that outputs the current time:

#!/bin/bash
echo "Server time: $(date)"
echo "CRON_TZ time: $(TZ=$CRON_TZ date)"

---

Many developers face issues when trying to schedule cron jobs based on client timezones rather than server time. The common misconception is that simply setting CRON_TZ in the cron command will automatically handle timezone conversion - but it doesn't work that way.

In your example:

32 16 08 05 * /usr/bin/curl CRON_TZ=Africa/Algiers https://www.example.com/SendCron.php?CronID=382

The CRON_TZ variable isn't being properly interpreted because:

• It's placed after the command rather than before
• cPanel's cron implementation may not support this syntax
• The timezone setting needs to be evaluated by cron itself, not passed to the command

Solution 1: Modify the PHP Script

The most reliable approach is to handle timezone conversion in your script:

<?php
// SendCron.php
date_default_timezone_set('Africa/Algiers');
$currentHour = date('H');
$currentDay = date('d');
$currentMonth = date('m');

if ($currentHour == 16 && $currentDay == 08 && $currentMonth == 05) {
    // Execute your email sending logic
    sendClientEmails();
}
?>

Solution 2: Server-Level Timezone Configuration

For systems using Vixie cron (common on Linux):

# In crontab file
CRON_TZ=Africa/Algiers
32 16 08 05 * /usr/bin/curl https://www.example.com/SendCron.php?CronID=382

Solution 3: Using UTC and Converting

Best practice is to always schedule in UTC and convert:

# Calculate Algiers time (UTC+1) by scheduling an hour earlier
32 15 08 05 * /usr/bin/curl https://www.example.com/SendCron.php?CronID=382

Always verify with:

# Check system time
date
# Check timezone
timedatectl
# Test cron syntax
crontab -l

For complex scheduling needs, consider libraries like:

• Python: APScheduler
• PHP: Cron Expression
• Node.js: node-cron

Example using PHP Cron Expression:

$expression = new Cron\CronExpression('32 16 08 05 *');
if ($expression->isDue(null, 'Africa/Algiers')) {
    // Run your task
}