monit-5.0.2-alt1 вылетает, если указана проверка файлов,
например после копирования syslogd из templates:

check file syslogd_bin with path /sbin/syslogd
<------>group syslogd
<------>include /etc/monitrc.d/templates/rootbin

check file syslog_file with path /var/log/syslog/messages
<------>group syslogd
<------>if timestamp > 65 minutes then alert        # Have you seen "-- MARK --"?
<------>if failed permission 640  then unmonitor
<------>if failed uid root        then unmonitor
<------>if failed gid adm         then unmonitor

Вылетает так:
[root@server monit.d]# [root@server monit.d]# monit -Iv        
...
'syslog_file' uid check succeeded [current uid=0]                              
'syslog_file' gid test failed for /var/log/syslog/messages -- current gid is 502
GID failed notification is sent to root@office.etersoft.ru                      
Monitoring disabled -- service syslogd                                          
Monitoring disabled -- service syslog_file                                      
monit: gc.c:167: gc_event: Assertion `pthread_mutex_destroy(&(*e)->mutex) == 0' failed.
Aborted