Mandrill on cPanel/WHM

Mandrill is a transactional email service run by MailChimp, comparable to SendGrid.  It comes stock with a powerful API for fast implementation into applications for sending email reliably over SMTP, but it can also be used as a smart host for all of your server’s outgoing email.

The below instructions cover how to do this via command line.  If you prefer WHM, simply go to WHM -> Exim Configuration Manager -> Advanced Editor and alter the sections indicated.

First, open up your /etc/exim.conf.local file in an editor and look for the @AUTH@ section.  Modify it to look like this:

@AUTH@
auth_login:
driver = plaintext
public_name = LOGIN
hide client_send = : your@email : api_key

Note:  If exim.conf.local doesn’t exist, create it.  There’s a template here.

The value of api_key is not your Mandrill account password – it’s your API key.  You can find it in your account settings under “SMTP & API Credentials”

Also, replace your@email with your Mandrill account email address.  If you already have something in the AUTH section, simply add this block of text below it.

Now look for the @PREROUTERS@ section, and modify it to look like this:

@PREROUTERS@
smart_route:
driver = manualroute
domains = ! +local_domains
ignore_target_hosts = 127.0.0.0/8
transport = auth_relay
route_list = * smtp.mandrillapp.com
no_more

The last modification should be to the @TRANSPORTSTART@ section:

@TRANSPORTSTART@
auth_relay:
driver = smtp
port = 587
hosts_require_auth = $host_address
hosts_require_tls = $host_address

Save this file.  Now open /etc/exim.conf.localopts and add this line (or modify it and append the hostname to the existing line)

smarthost_routelist=*: smtp.mandrillapp.com

If you’re using WHM, this is under Basic Editor -> Mail -> Smarthost support.

Save the file, and apply the changes:

/scripts/buildeximconf

service exim restart

To test whether things are working, send an email out from your server, and look for it in /var/log/exim_mainlog. You should see something like this in your log entry:

2014-03-11 21:59:50 1WNbGg-0006ud-2d => to@email R=smart_route T=auth_relay H=smtp.us-east-1.mandrillapp.com [x.x.x.x] X=UNKNOWN:ECDHE-RSA-AES256-GCM-SHA384:256 A=auth_login C="250 2.0.0 Ok: queued as 3529E193E178"

If you have SPF records, you’ll need to add the hostname of the SMTP server to the record itself to allow the third-party mail server to send email on behalf of your domain.  Mandrill will provide the hostname you should use underSettings -> Sending Domains, when you do an SPF test.

By thecpaneladmin.com