Zabbix triggers not sending email anymore

[moses.moore]

restarted zabbix server less than a day ago, and now it's not sending out email when triggers are fired off. I haven't changed the zabbix config, and it was able to send email.

How do I find out WHY Zabbix isn't sending email anymore? I looked in zabbix_server.log but no mention of failed attempts to send mail. I'm sure it didn't attempt to send mail, since I didn't find failed attempts in mail.log.

Screenshot where Zabbix says it didn't send email for a trigger: https://puu.sh/t6orZ/ce558eb665.png

[moses.moore]

resolved

Found it.

In zabbix_server.log :

1594:20170124:145252.958 cannot connect to SMTP server "localhost": cannot connect to [[localhost]:25]: [111] Connection refused
1594:20170124:145252.959 cannot connect to SMTP server "localhost": cannot connect to [[localhost]:25]: [111] Connection refused

But "telnet localhost 25" still works. The trouble is zabbix was using '::1' as the ipaddress for localhost -- IPv6. But telnet, /usr/lib/sendmail, /usr/bin/mail and everything else on the machine are using 127.0.0.1 -- IPv4.

Changed the local smtp daemon to listen on 127.0.0.1 and on ::1 and now it works.