Recommended settings for a local SMTP forwarder

We recommend that you use the following settings for your SMTP forwarder:

  • Configure the dedicated IP address that Contactlab assigns to your stream as a smarthost

    Ensures that every message will be forwarded to that address.

  • Set the timeout on the SMTP connection to at least 300 seconds

  • Limit the number of simultaneous outbound SMTP connections to eight

    The limit is configurable. Please let us know your needs.

  • Set the number of messages sent in a single connection to a reasonable limit, for example, 100

    We do not limit the number of messages delivered in a single connection, unless you require a specific setting. However, by doing this on your SMTP forwarder, you will usually help it manage its own outbound queue more smoothly.


  • You do not need to configure SMTP-AUTH

    We use the IP address(es) that you provide to us to limit inbound traffic.

  • You do not need to setup DKIM signing

    We sign your messages when delivering them to their destination.

Next page:

Using SmartRelay

Also see: