Aha!  There it is, on both the old and new systems, so it probably 
is running.  The question remains, "Why isn't it posting to email?"

On 3/11/2020 7:50 AM, Brad Campbell wrote:

On 11/3/20 09:11, Leslie Rhorer wrote:

quoted

     Is there seriously no one here who knows how checkarray was 
launched in previous versions?

On 3/1/2020 3:03 PM, Leslie Rhorer wrote:

quoted

    I have upgraded 2 of my servers to Debian Buster, and now 
neither one seems to be running checkarray automatically.  In 
addition, when I run checkarray manually, it isn't sending update 
emails on the status of the job.  Actually, I have never been able 
to figure out how checkarray runs.  One my older servers, there 
doesn't seem to be anything in /etc/crontab, /etc/cron.monthly, 
/etc/init.d/, /etc/mdadm/mdadm.conf, or /lib/systemd/system/ that 
would run checkarray.

On mine it's in /etc/cron.d/mdadm

brad@srv:/etc/cron.d$ cat mdadm
#
# cron.d/mdadm -- schedules periodic redundancy checks of MD devices
#
# Copyright © martin f. krafft [off-list ref]
# distributed under the terms of the Artistic Licence 2.0
#

# By default, run at 00:57 on every Sunday, but do nothing unless the 
day of
# the month is less than or equal to 7. Thus, only run on the first 
Sunday of
# each month. crontab(5) sucks, unfortunately, in this regard; 
therefore this
# hack (see #380425).
57 0 * * 0 root if [ -x /usr/share/mdadm/checkarray ] && [ $(date 
+\%d) -le 7 ]; then /usr/share/mdadm/checkarray --cron --all --idle 
--quiet; fi

dpkg -L mdadm gave me a list of files and I just checked the cron 
entries.

I don't run anything that recent, but Debian is Debian.

Brad