Virtual Domains and qmail
If you have hundreds of users for a virtual domain, you can avoid the hundreds of .qmail-xxx files with a small script that calls qmail's forward command.
Instead of creating individual .qmail-xxx files in the virtual domain master user's home directory, create a single .qmail-default file containing the following line:
with /home/master/qmail_db modified to reflect the home directory of your virtual domain. You can then create (or adapt from your existing /etc/aliases) the file /home/master/qmail_db, consisting of lines with the virtual domain user, a colon and the forwarding address(es). The special user name “-” indicates where mail should be forwarded for any users not explicitly listed. If the “-” user name is not provided, mail for nonexistent users will be bounced. A sample qmail_db file might look like this:
-: email@example.com john.smith: firstname.lastname@example.org carl.jones: email@example.com karen.quincy: kquincy all: firstname.lastname@example.org email@example.com kquincyNote the forwarding addresses for the “-” user must be an actual address; otherwise, mail to nonexistent addresses in the virtual domain will be accepted, but not delivered to anyone.
A more substantial package for supporting /etc/aliases, qmsmac, is available with qmail. qmsmac supports arbitrarily deep-nested aliases and long aliases but, like sendmail, requires you to rebuild a database of aliases every time your /etc/aliases file is changed.
qmail appears to be a speedy and robust replacement for sendmail. We've had qmail running on our Linux Internet server for many months now without a single glitch. The additional features provided by qmail could be useful to those of you hosting several virtual domains from a single Linux box, and the simpler configuration is an added bonus.
Free DevOps eBooks, Videos, and more!
Regardless of where you are in your DevOps process, Linux Journal can help!
We offer here the DEFINITIVE DevOps for Dummies, a mobile Application Development Primer, and advice & help from the expert sources like:
- Linux Journal
- New Products
- Readers' Choice Awards 2014
- Handling the workloads of the Future
- Android Candy: Google Keep
- How Can We Get Business to Care about Freedom, Openness and Interoperability?
- diff -u: What's New in Kernel Development
- Days Between Dates?
- December 2014 Issue of Linux Journal: Readers' Choice
- Computing without a Computer