Message Boards - post replys from your email client

My goal here will be to explain influence of pop.server.subdomain setting to setup external email server and enable Liferay 6.1 Message Boards to process email replies and post them to correct MessageBoards thread. For me, this feature is extremly handy because I can post to MessageBoards from my smart phone without need to sign in to portal.

Basic configuration requires just an dedicated email account for Liferay Portal. More advanced configuration requires:

have command line access to your email server
have available domain
access to domain register tools to create MX record and new domain aliases.

STEP 1 - Set your company data

First you will need to set your company host and mx record. You do next:

Go to Control Panel, Portal Settings - Set company domain to mydomain.com
Set email domain to mail.mydomain.com
Set liferay user email (eg. liferay@mydomain.com)
Go to server administration and click Email tab
According to this article (Step 2) set Incoming and Outgoing email server data

STEP 2 - Change portal-ext

This settings in portal-ext will allow us notifications and will discard email subdomain settings:

pop.server.notifications.enabled=true

pop.server.notifications.interval=1

pop.server.subdomain=

In this point you have basic configuration setup. Liferay will process replys and according to message subject your replys will be posted to right thread.

If you leave default subdomain setting:

pop.server.subdomain=event

or override it with some your value:
pop.server.subdomain=mboards

You will need to setup your email server to correctly process (forward) replys to liferay email account.

pop.server.subdomain=events will cause that liferay builds Message Boards email notifications to have reply-to attribute like mb_message.NNNNN.NNNNN@ events.mydomain.com. If your email server is not setup to handle emails to events.mydomain.com domain, replys will be rejected from destination email server with an error: The error that the other server returned was: 550 550 5.1.1 <mb_message.12204.12405@events.mydomain.com>: Recipient address rejected: User unknown in virtual mailbox table (state 14). If you set pop.server.subdomain property to empty string, portal would turnoff this feature. In that case reply-to email attribute would be set to email address set in your portal preferencies settings.

STEP 4 - Setup Email Subdomains

To make use of subdomains funcionality we will configure our email server to use virtual email inbox. That is needed bacause Liferay Portal will compose email notification messages such way that you will be replying your emails to generic unexisting users that will be later decoded to correct message boards threads. To achive that our users will be virtual and configured with regular expressions.

Use your domain admin tools to define mx record for mydomain.com and its aliases. In my case I have:

mail.mydomain.com as main mx record and
events.mail.mydomain.com as alias

Following postfix server setup example is done with dedicated postfix email server installed at Ubuntu OS with dovecot as POP3 server. Note that you might tune dovecot also.

At your email server host create user we will use to handle virtual inbox:

adduser --uid 500 --disabled-password --disabled-login vmail

Now change postfix main.cf to use virtual domains:

Line with mydestination setting must be commented out and we are adding new lines:

# mydestinations = mydomain.com

myhostname= mail.mydomain.com

mydomain = mydomain.com

# Virtual mailbox settings

virtual_mailbox_domains = events.mail.mydomain.com, mydomain.com

virtual_mailbox_base = /var/mail

virtual_mailbox_maps = pcre:/etc/postfix/vmailbox

virtual_minimum_uid = 100

virtual_uid_maps = pcre:/etc/postfix/virtual_uids

virtual_gid_maps = pcre:/etc/postfix/virtual_gids

virtual_alias_maps = hash:/etc/postfix/virtual_alias

virtual_mailbox_limit = 0

virtual_transport = virtual

local_transport = local

local_recipient_maps = $alias_maps $virtual_mailbox_maps unix:passwd.byname

Create files we will use to configure virtual domains and users. We already refer to those files in main.cf so without them postfix won't be able to startup:

/etc/postfix# cat vdomains