Advanced Cron Troubleshooting - Intermittent Issues
You may find that the cron job is not completing intermittently but does complete all of its tasks when you run it via the command line using these steps.
This type of issue may have many causes. You must perform additional investigation before you can determine next steps.
In order to investigate this issue, we recommend logging the output of the cron.php script to a file and then examining its contents.
If you use cPanel & WHM, this includes steps within WHMCS and in cPanel.
For more information for other control panels, see your server's documentation.
To investigate this issue on a cPanel & WHM server:
1. In the WHMCS Admin Area, go to the Other tab at Configuration > System Settings > General Settings or, prior to WHMCS 8.0, Setup > General Settings.
2. Select Display Errors.
3. Click Save Changes.
4. In cPanel, go to Advanced >> Cron Jobs.
5. Click Edit for the cron job command that references the
6. For Command, append the following code to the end of the line:
-vvv >> crondebug.txt
7. Click Edit Line.
8. Wait until the Time of Day window has passed. For example, if the Time of Day setting is 1pm, wait until 2pm.
9. Open the
crondebug.txt file in your account's
root directory. This file contains entries from each invocation of the
10. Review the file contents to locate the daily automation tasks. To find this, look for 24 or more tasks that queued for execution.
These will resemble the following examples:
- An error during execution:
WHMCS Automation Task Utility: all ================================== Queuing Tasks ------------- Applying "in progress" and "is due" state filters Task queues ready Executing Application Queue --------------------------- Currency Exchange Rates Product Pricing Updates Tenant Usage Metrics [ERROR] WHMCS\Exception\Module\NotServicable: Connection Error: Could not resolve host: fakeservertest(6) in /home/v80whmcssupport/public_html/whmcs/modules/servers/cpanel/cpanel.php:0
- A successful execution:
WHMCS Automation Task Utility: all ================================== Daily Cron Automation Mode Queuing Tasks ------------- Applying "in progress" and "is due" state filters Task queues ready Executing Application Queue --------------------------- Currency Exchange Rates Product Pricing Updates Invoices Late Fees Credit Card Charges Invoice & Overdue Reminders Domain Renewal Notices Cancellation Requests Overdue Suspensions Overdue Terminations Fixed Term Terminations Inactive Tickets Delayed Affiliate Commissions Email Marketer Rules SSL Sync Server Usage Stats Client Status Update Domain Expiry Ticket Escalation Rules Data Retention Pruning WHMCS Updates Run Jobs Queue Sending Daily Cron Digest email Executing System Queue ---------------------- [OK] Completed
11. Use the explanations of common errors in our documentation to continue resolving the issue.
WHMCS Technical Support can help you with these errors. When you open your support ticket, make sure to include the full output in your