Mail Delivery over the Internet
Understanding the basic principles of mail delivery over the Internet will help you correctly set your mailserver. This chapter gives a brief overview of the most important information on this topic. Experienced network administrators can skip this chapter.
The domain's primary mailserver does not always need to be the server where user mailboxes are stored. If the company to which the domain is registered connects to the Internet via a dial-up line, it can have a Domain Mailbox at its ISP. A domain mailbox is an account where mail for the entire domain is stored. The company's mailserver can retrieve mail from this mailbox (in certain time intervals) and sort the email into individual user mailboxes. The ISP's SMTP server where the domain mailbox is stored is listed as the primary mailserver for the company's domain in the MX records.
