De-duping attachments

[Joseph Brennan]

Outside the cyrus box:  The Mimedefang milter has a built-in function
(optional of course) to remove an attachment, write it to a file, and
replace the attachment part with a text part giving a web link to the
file.  The files could be on a slower type of disk drive than you need
for email storage.  You could write code choosing which attachments to
do this to, say by size or file extension.  A mechanism to remove the
files is not provided, but it's suggested that recipients would need
to download the attachment to their own computer and that therefore
the files could be deleted by a cron job based on age.

I mention this only as another way to do it.  Note that this could be
implemented for outgoing mail too.  We have not implemented it here
so I can't say more than that it is possible.

Joseph Brennan
Columbia University Information Technology