Ok I'm having a weird problem. We have a large amount of subscription renewals processed on the same day every month. About 400-500 subscriptions which are processed using an external cron via First Data. Some are being processed and some aren't being attempted at all. It seems like anywhere from 220-290 manage to actually get processed, the rest don't. It's not that they do and fail or are denied, it just doesn't try to rebill for them. I can't seem to find the problem, the only thing I can surmise is that the cron script is timing out and some are getting processed and others aren't. Any other ideas?
Yes this seems to be because of cron job. As solution, you can split all processes that should be run daily into separate cron jobs. So for example rebilling will run in one time and emailing in another. This should help. Contact me in helpdesk if you need exact examples.