postfix etwas verschärfen?

[joximu]

Wie wärs damit?
http://www.postfix.org/postconf.5.html#s...strictions

Quote:reject_unknown_client_hostname (with Postfix < 2.3: reject_unknown_client)
Reject the request when 1) the client IP address->name mapping fails, 2) the name->address mapping fails, or 3) the name->address mapping does not match the client IP address.
This is a stronger restriction than the reject_unknown_reverse_client_hostname feature, which triggers only under condition 1) above.
The unknown_client_reject_code parameter specifies the response code for rejected requests (default: 450). The reply is always 450 in case the address->name or name->address lookup failed due to a temporary problem.