High Frequency Cron Triggering & Differing POST URL

I recommend MailPoet to many of my managed website hosting clients, and most people love it. But my most recent client noticed (in Traffic Reports) high traffic coming from our own web server. On investigation, I found that MailPoet was triggering the cron script every few seconds, even though Newsletter Task Scheduler is set to activate from “Visitors to your website (recommended)”

It’s a newly launched site with very little traffic. But when I check server access logs, I see this:

52.38.252.35 - [03/Aug/2020:15:21:03 -0600] "POST /?mailpoet_router&endpoint=cron_daemon&action=run&data=eyJ0b2tlbiI6IjF1YmNrIn0 HTTP/1.0" 200 - "https://mrgwateradvocates.org/?mailpoet_router&endpoint=cron_daemon&action=run&data=eyJ0b2tlbiI6IjF1YmNrIn0" "MailPoet Cron"
52.38.252.35 - [03/Aug/2020:15:21:22 -0600] "POST /?mailpoet_router&endpoint=cron_daemon&action=run&data=eyJ0b2tlbiI6IjE5NTMyIn0 HTTP/1.0" 200 - "https://mrgwateradvocates.org/?mailpoet_router&endpoint=cron_daemon&action=run&data=eyJ0b2tlbiI6IjE5NTMyIn0" "MailPoet Cron"
52.38.252.35 - [03/Aug/2020:15:21:42 -0600] "POST /?mailpoet_router&endpoint=cron_daemon&action=run&data=eyJ0b2tlbiI6IjEzdTdhIn0 HTTP/1.0" 200 - "https://mrgwateradvocates.org/?mailpoet_router&endpoint=cron_daemon&action=run&data=eyJ0b2tlbiI6IjEzdTdhIn0" "MailPoet Cron"
52.38.252.35 - [03/Aug/2020:15:22:01 -0600] "POST /?mailpoet_router&endpoint=cron_daemon&action=run&data=eyJ0b2tlbiI6IjFwZzJkIn0 HTTP/1.0" 200 - "https://mrgwateradvocates.org/?mailpoet_router&endpoint=cron_daemon&action=run&data=eyJ0b2tlbiI6IjFwZzJkIn0" "MailPoet Cron"

There’s four triggers all within one minute. When I compare this access with a couple other sites on the same server, using same “Visitor” trigger settings, I see much less frequent triggering (more consistent with actual traffic) and the POST URL trigger also looks different…

52.38.252.35 - [03/Aug/2020:15:07:22 -0600] "POST /wp-cron.php?doing_wp_cron=1596488842.8253159523010253906250 HTTP/1.0" 200 - "https://www.churchalumni.org/wp-cron.php?doing_wp_cron=1596488842.8253159523010253906250" "WordPress/5.4.2; https://www.churchalumni.org"
. . .
52.38.252.35 - [03/Aug/2020:15:21:35 -0600] "POST /wp-cron.php?doing_wp_cron=1596489695.1383481025695800781250 HTTP/1.0" 200 - "https://www.churchalumni.org/wp-cron.php?doing_wp_cron=1596489695.1383481025695800781250" "WordPress/5.4.2; https://www.churchalumni.org"
. . .
52.38.252.35 - [03/Aug/2020:15:27:22 -0600] "POST /wp-cron.php?doing_wp_cron=1596490042.9619801044464111328125 HTTP/1.0" 200 - "https://www.churchalumni.org/wp-cron.php?doing_wp_cron=1596490042.9619801044464111328125" "WordPress/5.4.2; https://www.churchalumni.org"

(This was edited to remove visitor access URLs in between MailPoet cron triggers.)

Here, the trigger only happens when a visitor accesses the site. So what’s going on with my first site? What is causing this constant triggering? And why the difference in trigger access URLs between the two?

~ Pete O, webmaster

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