Sendmail: email from root every 20 minutes?

Question

linux

every 20 minutes I get an email in /var/mail/root
This is from sendmail, right? If so, how to disable it correctly so as not to break anything else?
[email protected]:~/# service sendmail status
MSP: is run via cron (20m)
MTA: 1588 /usr/sbin/sendmail-mta -Am -L sm-mta -bd -q10m
UID PID PPID C STIME TTY TIME CMD
root 1588 10 2019 ? 00:00:43 sendmail: MTA: accepting connections
Daemon Status: (process 20503) Console socket child
Current number of children: 0
QueueDir free disk space (in blocks): 148971532
Load average: 0
Child Process 1588 Status: accepting connections
QUE: Same as MTA

Answer 1

Hey, where's the letter???
To begin with, I advise you to look into the cron configs - perhaps something there instructs you to run something that sends a letter every 20 minutes. Or some daemon itself does it without cron.

Answer 2

If the job cron outputs something in the process of work, then the result is sent to the root by mail. To avoid this, in the crontab to the job you need to add>/dev/null 2>&1