Problem
The event log shows Milter (mailfilterd): timeout before data read, where=eom.
Solution
This may be caused by the following reason:
If an email message contains a shortened URI that redirects to another URI, the FortiMail unit is able to send a request to the shortened URI to get the redirected URI and scan it against the FortiGuard AntiSpam database. By default, this function is enabled. To use it, you need to open your HTTP port to allow the FortiMail unit to send requests for scanning the redirected URI.
This also means, if the upstreaming device (firewall, router, etc.) does not allow HTTP traffic from the FortiMail unit, FortiMail’s HTTP request to FortiGuard servers will get timeout.
To solve this problem
• Allow HTTP/HTTPS outbound traffic from the FortiMail unit on the upstreaming device.
or
• Run the following CLI commands on FortiMail to disable the feature:
config system fortiguard antispam
set uri-redirect-lookup disable
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