CNM Mail Server
CNM Mail Server (hereinafter, the Soft) is the server that makes sure that all CNM apps can send and, when applicable, receive emails through it.
Development of the Soft occurs under the Mail for CNM Cloud project.
Functions
- The purpose of a mail server is to allow users to send and receive emails securely.
- The mail server can:
- store incoming mail for distribution to local users and sends out outgoing messages;
- collect and distributes emails to their intended destination;
- encrypt the transfer of emails.
Product specification
- The Product specifications are:
- We use the most popular combination of Postfix and Dovecot for mail setup.
- Postfix is the Mail Transfer Agent. Postfix is free software, featuring a clever modular architecture that allows you to create a reliable and fast mail system.
- Dovecot is a free IMAP and POP3 server that offers security, configuration flexibility, and performance. Dovecot features are:
- High-performance
- A large number of supported mechanisms for storing authentication information (including LDAP) and authentication itself (SSL is supported).
- Extensibility via plugins.
- Strict adherence to standards. Dovecot is one of the few servers to pass all IMAP standards tests.
- We use the combination because Postfix just concerns itself with sending off client emails and temporarily storing incoming emails without sorting them according to recipient email address. And Dovecote's principal task is sorting the emails received by the mail transfer agent (MTA), e.g. Postfix, and delivering them on demand by each recipient. It separates the mass of emails arriving at Postfix's single mailbox into individual mailboxes for each recipient address and simultaneously listens for requests for a new email from recipients' email client packages.
- The architecture of the mail server looks like this:
- The input is the MTA mail server which works on the SMTP protocol. The MTA is on the Internet and it gets and sends the mail. We have some sort of mail base and we also have a mail delivery agent called MDA which delivers mail to the user. This is a POP3 or IMAP protocol. The MDA takes from the email base and gives it to the client. In between is the LDA, which takes mail from the MDA via LMTP (Local Mail Transfer Protocol) and puts it in the database.
- Usually, you don't put extra software as an LDA. Today, both Postfix and Dovecot can act as an LDA. But Postfix does it in a very primitive way. If you use Dovecot, however, it is possible to connect Sieve (a scripting language for mail filtering) and much more.
- Нow to install Postfix and Dovecot:
- Also antispam was installed. How to install Spam Assassin:
- You need to configure DNS correctly for the mail server to work properly. How to configure DNS:
- Email message management was set up in Dovecot. How to set up Email message management in Dovecot:
- Traffic was encrypted in Postfix. How to encrypt traffic in Postfix:
