Backup MX (Secondary SMTP Backup Service)


  • What is Backup MX?

    Backup MX is a service provided by Prolateral which gives you the ability to add a secondary (backup) SMTP server to your domain and act as a failover if your primary server becomes unavailable.

  • What is an MX Record?

    An MX (Mail eXchange) record tells email servers how to delivery email to your domain.

    Typically when you register a new domain several records are created for you. One of these records is the MX record so emails can be delivered to your mail server.

  • Can I have more than one MX Record?


    MX records have two values associated with them.

    The first is a priority number. The lower the number the more important the server (also called the primary mail server). If that server is unavailable then mail will attempt delivery to the next server with the next higher number. So lower the number higher the priority of server.

    The second value is the server name. Please note the server name must be a fully qualified domain name, and that record must equate to an A record. CNAME records are not supported

    So with multiple MX records you provide a more fault tolerant solution for email delivery.

  • How do I sign up for Backup MX?

    You can sign up for Backup MX by clicking here and be up and running within minutes.

    Sign up now for Backup MX

  • How can I tell what my MX records are?

    Using command tools like NSLOOKUP or DIG you can retreive your current MX record settings


    nslookup -q=mx

    dig -t mx

  • Do I need to purchase a domain name with you?


    But you will need to have purchased a domain with someone.

  • Do I need to transfer my domain name to you?


    As long as you have a domain and access to the DNS (Domain Name Service) records so you can update the MX records you will not need to transfer your domain name, unless you want to.

  • Can I keep my current domain name provider?


    But you will need access to the domain name providers DNS manager so you can update the MX records.

  • How do I update my MX records?

    If your company has its own DNS servers, talk to your DNS administrator. Otherwise, contact your domain name provider.

  • Do I need a second MX record?

    If you want to use Backup MX then YES!

    By using Backup MX and adding the second MX record you have increased your fault tolerance on email delivery, because if your server goes does down the backup smtp server will accept your emails until the primary is restored.

  • Will I lose email after updating my MX record?


    As long as you enter the MX records correctly, you won't lose any MX records. While your MX records are changing over, some mail will be delivered using your old MX information, and some mail will be delivered using your new MX information, but all of it will be delivered.

  • What happens if I type the wrong information into the MX record?

    If you type the incorrect delivery information in the MX record, some mail will bounce. The sender will receive a notice that the mail wasn't delivered.

    If this happens, correct the MX records as soon as possible.

  • What is Greylisting?

    Greylisting is a simple method of defending users against spam email. It is a great way of blocking most spam without using content filters.

    Greylisting will “temporarily reject” (a SMTP 450 error code) any email from a sender it does not recognise. If the email is legitimate the originating server will try again within a few minutes, at which time the email will be accepted. If the mail is from a spammer, it will not be retried so the spam will not be relayed through our systems and on to your mail server.

  • What is RBL?

    RBL stands for Realtime Block List or Realtime Black List.

    RBL servers are used, run and hosted by spam filtering companies like Prolateral which contain a realtime list of IP Addresses of servers that are known to generate spam.