cat /var/log/syslog | grep cron
Setting up cron.log file
First off go to /etc/rsyslog.d/50-default.conf file and search for
this line #cron.* /var/log/cron.log
 cat /etc/rsyslog.d/50-default.conf | grep cron
Output
#cron.*                         /var/log/cron.log
#       cron,daemon.none;\
Using your favorite text editor, open the file and uncomment the line as shown in line 10