root@skipper:/home/askold# tail -f /var/log/zabbix/zabbix_server.log | grep mail
29169:20210612:215822.395 trapper got '{"request":"alert.send","sid":"326d0d8e97e4b88d9d4ab96d0b0e307e","data":{"sendto":"MAIL_BOX@gmail.com","subject":"Test subject","message":"This is the test message from Zabbix","mediatypeid":"11"}}'
29169:20210612:215822.396 query [txnlev:0] [select type,smtp_server,smtp_helo,smtp_email,exec_path,gsm_modem,username,passwd,smtp_port,smtp_security,smtp_verify_peer,smtp_verify_host,smtp_authentication,exec_params,maxsessions,maxattempts,attempt_interval,content_type,script,timeout from media_type where mediatypeid=11]
29192:20210612:215822.397 In send_email() smtp_server:'
smtp.gmail.com' smtp_port:465 smtp_security:2 smtp_authentication:1
29192:20210612:215828.738 End of send_email():SUCCEED