Using Zimbra shared folders to simulate "discussion forums"

[fcash]

We're looking for a way to create a "discussion forum" kind of setup in Zimbra, where people can post messages, read old messages, reply to messages, etc.

I've found a method that does just about everything we need ... with one very glaring issue. Here's the setup:

• zimbra account called "math-forum" created, logins disabled except via "View Mail" from admin console
• Inbox for math-forum is shared out to people with "viewer" role
• people can post messages via e-mail to "math-forum"
• people can view messages via the shared folder
• people can reply to these messages same as any other message
• only admin users can delete messages

The issue is that when people hit reply while reading messages in the shared folder, the message is addressed to the person who sent the message, and not to "math-forum". Which makes sense, as that is how e-mail works (you reply to the sender, not the recipient). And one can use reply-all to kind of work around that (except it puts the math-forum address into CC: instead of TO:, so people have to cut/paste, etc).

What I was wondering is if anyone knows of a way to:

• rewrite the "Reply-To" header on messages sent to "math-forum" to put the "math-forum" address in (making replies go back to the "math-forum", but keeping the From header intact), or
• force replies to messages in a shared folder to always go to a certain address, or
• create "discussion forums" within Zimbra

Unfortunately, the filters interface in Zimbra doesn't have a "re-write header X to Y" or "add header X" option. That would be the simplest solution, as we could then configure the account with a filter that added/re-wrote the Reply-To header to the address of the account.

The second option would probably take a lot of re-working the zimbra internals and be a pain to administer.

The third option would be best long-term solution, as it would require using up licenses for each forum.

If distribution lists were more like mailing lists where the Reply-To header was set to the address of the list, then this would be a moot point, and could be done via mailing lists and shared folders. [hint, hint]

Suggestions? Comments? Criticisms?

[fcash]

Originally Posted by fcash

What I was wondering is if anyone knows of a way to:

• rewrite the "Reply-To" header on messages sent to "math-forum" to put the "math-forum" address in (making replies go back to the "math-forum", but keeping the From header intact)

Unfortunately, the filters interface in Zimbra doesn't have a "re-write header X to Y" or "add header X" option. That would be the simplest solution, as we could then configure the account with a filter that added/re-wrote the Reply-To header to the address of the account.

Would this be possible to do via Postfix? Or perhaps via CLI access to the SIEVE engine?

[Rabid]

Originally Posted by fcash

Would this be possible to do via Postfix? Or perhaps via CLI access to the SIEVE engine?

I need this, too, and I voted for this feature in Bugzilla #15664. You should vote for it, too, that would make four of us.

Meanwhile, I'm trying to learn how to modify my Zimbra's Postfix configuration to rewrite the Reply-To header for inbound messages sent to specific addresses (Zimbra distribution lists). I've found no examples, but I'm starting with this information. Any help from Postfix gurus here would be appreciated.

[davidfsmith]

Originally Posted by Rabid

I need this, too, and I voted for this feature in Bugzilla #15664. You should vote for it, too, that would make four of us.

Meanwhile, I'm trying to learn how to modify my Zimbra's Postfix configuration to rewrite the Reply-To header for inbound messages sent to specific addresses (Zimbra distribution lists). I've found no examples, but I'm starting with this information. Any help from Postfix gurus here would be appreciated.

I'll vote for that one ;-)

[fcash]

I ended up using header_checks in postfix to add the Reply-To: header when it came across certain To: headers. Not perfect, but it's workable for now until real Mailing List management tools are added (or better Mailman integration is possible).

if /^To: math-forum/
/^To: math-forum/ PREPEND Reply-To: math-forum@domain
endif

[Rabid]

Originally Posted by fcash

I ended up using header_checks in postfix to add the Reply-To: header when it came across certain To: headers. Not perfect, but it's workable for now until real Mailing List management tools are added (or better Mailman integration is possible).

if /^To: math-forum/
/^To: math-forum/ PREPEND Reply-To: math-forum@domain
endif

Thanks, Freddie, I'm going to give your tip a try.

[Rabid]

Well, that worked OK for the first recipient's reply to the message sent to the list, but subsequent recipients' replies are addressed to the sender, and not the list, for whatever reason.

[Rabid]

OK, I think I figured this out, for my specific needs.
Recapping, I wanted to achieve just this one feature of "Discussion Forum/List" management, (which I used to have in majordomo on my old email server):
Recipients of messages to a distribution list click "Reply" in their email client, and their reply goes to the list, not just the original sender.
(Training the recipients to click "Reply-all" has proven futile. Human behavior and such, meh.)

The email clients I tested for this solution are Eudora 4.3.2, (older than dirt, I know), Outlook Express 6.00, MS Office Outlook 2003, and Zimbra UI 4.5.10.

To make it work, I started with the suggestion in this thread from Freddie (thanks very much!).
I had to add another test to look for angle-bracketed "To:" addresses so that replies to the first reply also go to the distribution list.
Apparently, the angle-brackets, < >, appear around the To: address only after the first recipient replies to the original message, I don't know why.

I added rules to header_checks in postfix as follows:
On my Zimbra 4.5.10 server, logged in as user zimbra, in the directory, /opt/zimbra/conf , I made the file, postfix_header_checks.in, writable by zimbra with:
# chmod u+w postfix_header_checks.in

I edited that file to append these lines:

if /^To: list1@mydomain.com/
/^To: list1@mydomain.com/ PREPEND Reply-To: list1@mydomain.com
endif
if /^To: <list1@mydomain.com>/
/^To: <list1@mydomain.com>/ PREPEND Reply-To: list1@mydomain.com
endif
if /^To: list2@mydomain.com/
/^To: list2@mydomain.com/ PREPEND Reply-To: list2@mydomain.com
endif
if /^To: <list2@mydomain.com>/
/^To: <list2@mydomain.com>/ PREPEND Reply-To: list2@mydomain.com
endif

The additional angle-bracket entries, above, allow the reply-to-list feature to continue to work after the first recipient's reply, such that subsequent replies also went to the list, (at least they did in my testing.)

Then I did a
# postfix reload
and ignored these warnings:

postmap: warning: /opt/zimbra/conf/postfix_header_checks, line 6: record is in "key: value" format; is this an alias file?
postmap: warning: /opt/zimbra/conf/postfix_header_checks, line 7: expected format: key whitespace value
postmap: warning: /opt/zimbra/conf/postfix_header_checks.db: duplicate entry: "if"

The warnings could probably be suppressed if I knew the right syntax to put into postfix_header_checks.in, but this solution works, for me, for now.
By editing the file, postfix_header_checks.in, my changes should survive a server reboot, but probably not a Zimbra upgrade.

If I get some feedback of interest, I'll post or append-to a pertinent Zimbra Wiki article.

[Rabid]

Originally Posted by Rabid

By editing the file, postfix_header_checks.in, my changes should survive a server reboot, but probably not a Zimbra upgrade.

As expected, after upgrading to Zimbra 5.0.5, my customizations described above were lost, but I was able to restore them by repeating the steps outlined, above.

[JeeZ]

Hi!

It worked for me too. And I also added the CC field :

if /^To: list@domain.com/
/^To: list@domain.com/ PREPEND Reply-To: list@domain.com
endif
if /^To: <list@domain.com>/
/^To: <list@domain.com>/ PREPEND Reply-To: list@domain.com
endif
if /^Cc: list@domain.com/
/^Cc: list@domain.com/ PREPEND Reply-To: list@domain.com
endif
if /^Cc: <list@domain.com>/
/^Cc: <list@domain.com>/ PREPEND Reply-To: list@domain.com
endif

But in my case, "postfix reload" didn't worked ... I had to
"zmcontrol stop; zmcontrl start" to make it work.

Please vote for Bug 15664 &ndash; Add reply-to option for distribution lists to make this feature built-in in the Administrative Console !

Have a nice day!
JeeZ