Linux Mail Servers - Friday, July 18, 2008 16:51 - 0 Comments

Linux mail servers

Overview of Linux mail servers

Mail servers are used to send mail and receive mail from servers all over the world.  Many different servers are used for this purpose, this article will overview the Linux mail servers SendMail, Postfix, Exim and Qmail. SendMail has gone through many revisions to help combat today’s ever growing needs and is currently available in version 8.14.3. Sendmail.org recommends the installation of DKIM with all Internet-facing SendMail and Postfix MTAs. This extra application is supposed to help deter phishing, fraud and spam. BSD Unix is the recommended platform fro SendMail to run on, however other another OS can be used if it is not feasible to have a different platform than the rest of the network. Support for SendMail can be found at www.sendmail.org.

Another Linux mail server is Postfix; Postfix is an alternative to SendMail and comes from IBM research. Postfix claims to be fast, easy to work with, and secure. It has the feel of SendMail but the inner workings are completely different. The platforms that support Postfix are AIX, BSD, HP-UX, IRIX, LINUX, MacOS X, Solaris, Tru64 UNIX, and other UNIX systems. Postfix has certain requirements for running the first requirement is that the file system has the capability to rename a file to another close directory without the files inode number changing. Another requirement is that a file is able to be hard linked between different directories. Lastly, that mail is safely stored after the fsync ( ) of that returns with success. Some Postfix features are junk mail control, database support, mailbox support, protocol support and address manipulation.

Exim is yet another one of Linux’s offering in the mail server category. Exim was created at the University of Cambridge for use on Unix systems connected to the Internet. Its interface is similar to Smail 3; however its features are more simplified. The current version available is 4.69 and is open source and free to download from www.exim.org. Exim does not support POP or IMAP protocols; however Exim can deliver mail to other mail servers that do have this feature. Exim also does not have a GUI; it is a very basic mail server for sending and receiving mail in the simplest fashion.

Qmail is the answer to SendMail is trying to be the universal SendMail replacement.  Qmail has commercial support, user contributed documentation, and is currently releasing version 1.06. Major Websites use Qmail as their primary mail server, such as Yahoo, Pay Pal, and Net Zero.  If there is anything that Qmail lacks, it is likely that there is an enhancement file to download to make Qmail act they way you want. Qmail support, files, and comprehensive information can be found at
www.gmail.org.

Article written by MyComputerAid.com