One of the easiest ways to get a random Ubuntu (or any other server) to talk nicely with SMTP and actually reach your inbox is by using a third party mailing service such as Sendgrid. In general, we want to allow email alerts from the server when bad or important things happen, such as a parser breaking, or an IP gets banned .If these emails end up in the abyss, or worse, in your spam box – then we would be missing out on important events. For this reason, it’s important to verify that your mai server is running happily and sending all emails before continuing out setup. Sendgrid is easy to set up, and free for the mail volumes we will be using. Go ahead and sign up with them, and get your SendGrid API Key.