In this scenario, alertemail is already configured but nothihing is received.
In case it is not configured, it is possible to follow this document and configure automation stritch as per requirement:
Flow of alertemail.
Initially alertmail will be triggered, firewall will try to send email to destination mail server as per the configuration made under System -> Settings.
1) As soon as automation stritch is triggered, go to Log & report -> Events -> System Events (saying that automation stritch is triggered).
2) Verify the configuration of email server, made under System -> Settings.
- If port 25 is used, SMTP security must set to none
- If port 587 or port 465 is used, SMTP security must set to SMTPS or STARTTLS.
Once the changes have been made, if is still not possible to send email:
- Try to take sniffer with that specific port:
# diag sniffer packet any 'port 587 or port 25' 4 0 a
Observe the traffic flow, if it is going only out side and there is no IN packets, it means you need to check at the next hop level.
Final step, is there are some mail servers when the mail is coming from 'no reply' they will filter the emails.
It is possible to configure email from field using this article under (automation system action):