Set up a Mail Relay

Because the system dynamically assigns IP addresses in Cloud Servers, the IP space is unfit for email use. This means that major blacklist providers declare that mail systems should not accept email coming from cloud servers. For this reason, email from cloud servers might not reliably get through to your intended recipients.

To send email reliably from your server, we recommend you sign up for a Rackspace Email account, or use any email account that allows you to send email through secure SMTP authentication. You can then configure your server to send email through that account. This way, you can still send mail from the server and avoid these issues.

This article helps with that setup, showing you how to set up a relay with Rackspace Email by using a smarthost. The same basic steps work for most email providers. This solution targets system-generated emails, like sign-up scripts, password confirmation pages, and so on that you cannot otherwise easily route through an outside mail provider. Depending on your email needs, you might need to configure an account with a third-party like Mailgun®, Mailchimp®, or SendGrid®.

Managed Support customers can contact support and ask us to do this for you. Provide the email server and the username and password for the account that you want to send mail. Other Cloud Servers customers can set up the relay by following the steps in this article.

Set up a relay

Perform the folloinwg dteps to set up an email relay:

1. Install postfix and SASL tools.

   For Red Hat® Enterprise Linux® or CentOS®:

    yum install postfix cyrus-sasl-plain cyrus-sasl-md5
   

   For Ubuntu® operating systems:

    aptitude update
    apt-get install postfix libsasl2-modules
   

2. Configure postfix.

   a. Add the following lines to /etc/postfix/main.cf:

    relayhost = secure.emailsrvr.com
    smtp_sasl_auth_enable=yes
    smtp_sasl_password_maps=hash:/etc/postfix/sasl_passwd
    smtp_sasl_mechanism_filter = AUTH LOGIN
    smtp_sasl_security_options =
   

   b. Add the Rackspace Email username and password to /etc/postfix/sasl_passwd by running these commands:

    echo 'secure.emailsrvr.com username@domain.com:secretpassword' > /etc/postfix/sasl_passwd
    chmod 600 /etc/postfix/sasl_passwd
    postmap /etc/postfix/sasl_passwd
   

   c. Restart Postfix and check the mail logs. You should see something like the following output:

    Nov 23 10:46:05 web2 postfix/qmgr\[24259\]: 5497F3708AA:
    from=<orders@myawesomeecommercesite.com>, size=1762, nrcpt=1 (queue active)
    Nov 23 10:46:05 web2 postfix/smtp\[1343\]:497F3708AA:to=<customer@someisp.com>,
    relay=secure.emailsrvr.com\[98.129.185.2\]:25, delay=0.31, delays=0.02/0.01/0.19/0.1,
    dsn=2.0.0, status=sent (250 2.0.0 Ok: queued as B5E3D2D0476)
   

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