Fortimail outgoing emails delay

[CL1]

Morning everyone,

I'm experiencing a delay with outgoing emails and would like to know if there are any additional troubleshooting steps I might have missed.

Thanks in advanced

Kind regards,

[AEK]

Hello CL1

Open the monitoring menu, and find the related outgoing e-mail in history, then clich on the entry in the session column (session id).

There in the session details you can find which step is taking much time.

[CL1]

Hey AEK,

Thank you for your response. I actually did that step yesterday, and interestingly everything seems to be functioning normally. There's only about 0.2 ms of inspection time. I'm currently troubleshooting on the SMTP server side, as I suspect the issue lies between the communication of FortiMail and exchange.

Kind regards,

[AEK]

Hi CL1

Also check the mail queue of both FML and mail server while you are noticing the delay.

[CL1]

Hello AEK,

Yes I’ve reviewed everything and identified the issue. It appears to be a networking related problem, the communication between the mail server and FortiMail. Specifically, the mail server is sending RST packets to FortiMail during the threeway handshake. What I dont understand is how emails are being forwarded (with a delay) even tho the mail server is sending those RST messages ? 

Any thoughts ?

Kind regards

[AEK]

Probably the mail server is "intermittently" sending RST. It means sometimes the connection is on and the mail is sent.

I'd check the mail server configuration and logs. Maybe the server is limiting the incoming connections from FML or something similar.

[CL1]

There was no change on the mail server configuration, I'll try to troubleshoot even more and see.

Thank you so much for your help

Kind regards,