Set up local bounce processing¶

If you're setting up CiviMail, you'll need a bounce processing account on a system that supports subaddressing. GMail/Google Apps works for this - Exchange and Office 365 do not. So it's often desirable to set up your own server for bounce processing - it takes very little overhead, so you can run it on the same VPS that runs CiviCRM.

Create a user account: useradd -s /dev/null -m civibounces. Also set the password with passwd.
Install Postfix: apt-get install postfix. Select all the standard options.
Make sure your DNS A and PTR records are set up properly! You should also have an MX record, though you can get away with not having it if the domain's A record points to the server.
Install Dovecot. In theory this is unnecessary - you can specify a mailbox on localhost - but I've had less trouble with this approach. In Debian/Ubuntu: apt-get install dovecot-imapd. You can skip SSL since it's all over localhost.
Create a user whose name will be the e-mail address. E.g. for civi-bounces@mysite.org, useradd -m civi-bounces -s /sbin/nologin. Add a password to the user account.
For Debian, drop this file into /etc/dovecot/conf.d/99-mysettings.conf to configure dovecot.
```
protocols = imap
disable_plaintext_auth=no
mail_location = mbox:~/mail:INBOX=/var/spool/mail/%u
mail_privileged_group = mail
```
- For CentOS this needs to be added to the mail /etc/dovecot/dovecot.conf file. And the permissions need to be changed per this.
(Pretty sure this is NOT required on Debian 8, but maybe on other versions/distros): chmod g+rw /var/spool/mail/*
Check /etc/postfix/main.cf to ensure that mydestination includes the domain you want to deliver mail to (e.g. "mysite.org").
Open port 25 in your incoming firewall.
- Linode has no firewall.
- Amazon EC2 can be configured in the AWS Console.
- Blackmesh managed servers have firewall that you need to submit a ticket to to open ports.
You should now be able to use this account for IMAP! Punch a temporary hole in your firewall at port 143 to access it from outside and connect Thunderbird to the account. Send a test message, of course.
Configure the Bounce Processing account in CiviCRM as you would any other IMAP-based account.