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:
-: firstname.lastname@example.org john.smith: email@example.com carl.jones: firstname.lastname@example.org karen.quincy: kquincy all: email@example.com firstname.lastname@example.org 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 Webinar: Hadoop
How to Build an Optimal Hadoop Cluster to Store and Maintain Unlimited Amounts of Data Using Microservers
Realizing the promise of Apache® Hadoop® requires the effective deployment of compute, memory, storage and networking to achieve optimal results. With its flexibility and multitude of options, it is easy to over or under provision the server infrastructure, resulting in poor performance and high TCO. Join us for an in depth, technical discussion with industry experts from leading Hadoop and server companies who will provide insights into the key considerations for designing and deploying an optimal Hadoop cluster.
Some of key questions to be discussed are:
- What is the “typical” Hadoop cluster and what should be installed on the different machine types?
- Why should you consider the typical workload patterns when making your hardware decisions?
- Are all microservers created equal for Hadoop deployments?
- How do I plan for expansion if I require more compute, memory, storage or networking?
|Speed Up Your Web Site with Varnish||Jun 19, 2013|
|Non-Linux FOSS: libnotify, OS X Style||Jun 18, 2013|
|Containers—Not Virtual Machines—Are the Future Cloud||Jun 17, 2013|
|Lock-Free Multi-Producer Multi-Consumer Queue on Ring Buffer||Jun 12, 2013|
|Weechat, Irssi's Little Brother||Jun 11, 2013|
|One Tail Just Isn't Enough||Jun 07, 2013|
- Speed Up Your Web Site with Varnish
- Containers—Not Virtual Machines—Are the Future Cloud
- Non-Linux FOSS: libnotify, OS X Style
- Lock-Free Multi-Producer Multi-Consumer Queue on Ring Buffer
- Linux Systems Administrator
- Senior Perl Developer
- Technical Support Rep
- UX Designer
- Android's Limits
- Reply to comment | Linux Journal
8 min 13 sec ago
- Yeah, user namespaces are
1 hour 24 min ago
- Cari Uang
4 hours 55 min ago
- user namespaces
7 hours 49 min ago
8 hours 15 min ago
- One advantage with VMs
10 hours 43 min ago
- about info
11 hours 16 min ago
11 hours 17 min ago
11 hours 18 min ago
11 hours 20 min ago