Troubleshooting the System Cron

If you encounter errors or issues involving the system cron or its daily automation tasks, see the sections below to start troubleshooting and resolve the issue.

You can troubleshoot cron-related issues using the steps in Check the Cron Job Status and Cron Failures.

For more information, see System Cron.

Cron Errors

You may encounter the following common issues:

Error or IssueExplanationNext Steps
During the daily automation cron run, the script takes a long time to complete, especially during the Executing System Queue step.The PHP process to generate and zip the database backup can take a long time to process on resource-restricted servers.Cron System Queue Timeout
The cron successfully finishes all of its tasks when you run it manually, but some cron job runs still do not succeed.This type of issue may have many causes. You must perform additional investigation before you can determine next steps.Intermittent Cron Failures
The daily cron run is failing due to timeouts while polling your servers for usage statistics.There is a connection issue between WHMCS and your hosting servers.Cron Metrics Polling Timeout
The system is attempting to invoke the system cron correctly, but the cron job is not completing the run.Cron tasks can fail for many reasons. Check the exact error to determine the cause.Cron Failures
You see a warning about the hour at Configuration () > System Settings > Automation Settings or receive a WHMCS Daily System Cron Attention Needed email.There is a problem with the system cron configuration.Cron Time of Day Issues
You see a warning message stating that the system cron has not run within the past two hours.There is a problem with the system cron configuration or a timezone mismatch.Cron Frequency Warnings
Could not connect to databaseThis error indicates that the system cron cannot connect to your database.Could Not Connect Errors
Could not open input file: /path/to/crons/cron.phpThe cron.php file is not present in the specified directory path.Cron Input File Errors
Error: Call to undefined function curl_init()The cURL extension is not installed or the curl_init function is disabled.Undefined curl_init() Function Errors
Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 20480 bytes)
or
The cron run does not finish.
The cron job exceeded your memory_limit value.Fatal Memory Size Errors
No input file specifiedThe path to the cron.php file in your server’s cron job configuration is invalid.No Input File Specified Errors
Unable to communicate with the WHMCS installationThis error occurs when the cron.php file cannot communicate with the WHMCS installation.Unable to Communicate Errors

Last modified: May 31, 2024