On Fri, May 08, 2015 at 12:52:40AM +0500, Kashif Ali Bukhari wrote:
> I have u...@example.com created onpostfix. (MX entry is
> mail.example.com and the old mx entry was
> example-com.mail.eo.outlook.com).
OK.
> All email successfully delivered to u...@example.com's local mailbox.
OK.
> Now I want email for u...@example.com should be delivered to local
> mailbox and a copy sent u...@example.com via
> example-com.mail.eo.outlook.com , (remember MX recored
> example-com.mail.eo.outlook.com is removed from example.com) so that
> if user login to microsoft365 he wont miss email.
Can you arrange for Microsoft to disable SPF checks on mail you
want to forward to the user's Office365 hosted mailbox?
If you can't negotiate that with them there's no point considering
how to implement the Postfix side unless you want to jump through
hoops with SRS (too complicated for mortals I think).
If you can negotiate that, then we'd need to change the local
delivery address for each user, and route the original address
to example-com.mail.eo.outlook.com.
virtual:
# Replace user@localhost with whatever alternative mailbox
# name works for local delivery.
#
u...@example.com u...@example.com, user@localhost
transport:
example.com smtp:[example-com.mail.eo.outlook.com]
There are other ways of doing this, but they're more complex.
Nothing is workable if Microsoft will apply SPF anti-spam
filters to mail you forward.
--
Viktor.
