Viktor, >>This rather severely limits the usability of your MSA. It cannot support >>ordinary email sent to multiple recipients or Bcc'ed. Also you say this is >>an MSA, and >>yet claim the mail is sent by external senders outside OSU. >>How are these two statements compatible? Is this an MSA processing outbound >>mail generated >>internally at OSU, or simply an outbound relay, forwarding >>mail whose recipients are external to your email systems (possibly your users >>hosted outside). >>Explain your system more clearly.
Main email system is Microsoft exchange system. The Exchange Hub servers deliver the all outbound mails (internal users send emails to external users or external users send emails to internal users BUT whose email addresses are forwarding to his/her external mailboxes) to Postfix servers. The postfix servers receive all emails which the recipient addresses are external email addresses. So I think it simply an outbound relay, forwarding mail whose recipients are external to your email systems. >>Mail you've accepted (whether inbound or outbound) that is then forwarded to >>Microsoft for a hosted mailbox SHOULD NOT be spam filtered by Microsoft. >>>>That resposibility falls on your systems as the original systems that >>receive the mail from the external sender. Currently the situation is all outbound emails are sent to MICROSOFT antispam system - EOP for scanning before they are delivered to destination external mailboxes. Sometimes internal users' mailboxes are possibly compromised to be abused to send a lot of outbound junks. >>The systems you use to forward mail to Microsoft for your own hosted users, >>MUST be whitelisted by Microsoft for delivery to the hosted users in >>question, >>with NO spam filters applied by them. The fact is the systems we currently use are not whitelisted by Microsoft for delivery to the hosted users in question with NO spam filters applied by them. As I say above - Sometimes internal users' mailboxes are possibly compromised to be abused to send a lot of outbound junks. >>If Microsoft cannot do this for you, find a better email hosting provider. >>You're wasting time attacking the wrong problem. The decision will be made by higher level of managements, not me. Sometimes the effort used to attack the wrong problem is not fairly wasting time. Thanks, Carl -----Original Message----- From: owner-postfix-us...@postfix.org [mailto:owner-postfix-us...@postfix.org] On Behalf Of Viktor Dukhovni Sent: Tuesday, August 05, 2014 5:46 PM To: postfix-users@postfix.org Subject: Re: How to fetch From address from header via Postfix head_check? On Tue, Aug 05, 2014 at 09:28:24PM +0000, Xie, Wei wrote: > > What you're proposing is not viable, and seems to serve no purpose. > > You should explain the problem you're trying to solve by adding > > these, rather than the problems you're having doing so. > > When the message hits our outbound Postfix servers, on an MSA the "To:" > address only list one recipient. We do not need consider multiple > recipients. This rather severely limits the usability of your MSA. It cannot support ordinary email sent to multiple recipients or Bcc'ed. Also you say this is an MSA, and yet claim the mail is sent by external senders outside OSU. How are these two statements compatible? Is this an MSA processing outbound mail generated internally at OSU, or simply an outbound relay, forwarding mail whose recipients are external to your email systems (possibly your users hosted outside). Explain your system more clearly. > The problem is the nexthop - Microsoft antispam system due to their > bugs is eating some outbound emails from non-osu.edu or > non-ohio-state.edu senders to forwarding accounts. But their system > does not eat the emails which are "Resent-From" from mailbox users > ("Resent-From:" is appropriate when a user takes a message delivered > to his mailbox (possibly long after initial delivery) and resends it > to another user (typically not an original recipient). Our exchange engineers > ask whether Postfix can add "Resent-From: > <original to address>" for emails to forwarding accounts like mailbox > accounts resent the emails to bypass Microsoft antispam system (this > is one of all kinds attempts). Mail you've accepted (whether inbound or outbound) that is then forwarded to Microsoft for a hosted mailbox SHOULD NOT be spam filtered by Microsoft. That resposibility falls on your systems as the original systems that receive the mail from the external sender. The systems you use to forward mail to Microsoft for your own hosted users, MUST be whitelisted by Microsoft for delivery to the hosted users in question, with NO spam filters applied by them. If Microsoft cannot do this for you, find a better email hosting provider. You're wasting time attacking the wrong problem. -- Viktor.
