Book Summary:
Life with qmail is aimed at everyone interested in running
qmail, from the rank amateur (newbie) who just installed Linux on a spare PC all the way up to the experienced system administrator or mail administrator.
qmail is an Internet
Mail Transfer Agent (MTA) for UNIX-like operating systems. It's a drop-in replacement for the
Sendmail system provided with UNIX operating systems. qmail uses the
Simple Mail Transfer Protocol (SMTP) to exchange messages with MTA's on other systems. Learn about SMTP and how companies utilize these mail servers like
Jango SMTP Server users do.
There's a wealth of information available on qmail from a variety of sources. Some is targeted to newbies, some assumes that the reader is more experienced.
Life with qmail is an attempt to "glue" this information into a single source, filling in some of the cracks and assuming only that the reader has basic skills such as:
- Manipulating files/directories under UNIX
- Operating a web browser or FTP client
- Following directions
Why use qmail:
Your operating system included an MTA, probably Sendmail, so if you're reading this document you're probably looking for something better. Some of the advantages of qmail over vendor-provided MTA's include:
- Security
qmail was designed for high security. Sendmail has a long history of serious security problems. When Sendmail was written, the Net was a much friendlier place. Everyone knew everyone else, and there was little need to design and code for high security. Today's Internet is a much more hostile environment for network servers. Sendmail's author,
Eric Allman, and the current maintainer,
Claus Assman, have done a good job of tightening up the program, but nothing short of a redesign can achieve true security.
- Performance
qmail parallelizes mail delivery, performing up to 20 deliveries simultaneously, by default.
- Reliability
Once qmail accepts a message, it guarantees that it won't be lost. qmail also supports a new mailbox format that works reliably even over NFS without locking.
- Simplicity
qmail is smaller than any other equivalently-featured MTA.