A VPN is an effective way to keep remote workers and branch offices as secure as those in HQ. A VPN server plays a major role in this architecture. We continue our look at how to set up a VPN server, from stepping though how to enable the OpenVPN server and copy in SSL certificates, to configuring clients and testing.

Google tools are useful. If you're an Ubuntu or Debian user, you can now get even more out of them with GoogleCL.

Most admins know WebDAV, but davfs2 isn't as well known. With this open source software tool, you can connect to WebDAV server as a regular filesystem, thus allowing applications that don't support WebDAV to access shared resources via WebDAV.

A VPN enables users to remotely access file or connect remote offices together via secure tunnels over the Internet. If you're building a VPN for more than two-dozen VPN users, setting up a VPN server is a viable option. Find out how to do so using DD-WRTDD-WRT router firmware.

Life may not come with an undo button, but fortunately open source software does. With the open source software, Git, it's all too easy to unintentionally commit a file. Fortunately, it's also easy to turn back time.

With Sudo, a sys admin can allow certain users to run commands as root or another user while providing an audit trail of the commands and their arguments. Unfortunately, increased privileges usually apply only to the first command typed. Here's how to extend them to any input or output redirection.

Commandlinefu is a simple repository for storing and sharing shell commands with the rest of the world. Here are three new command-line one liners that stand out.

Tip of the Trade: Type 'history' at the Bash command prompt, and you'll get a list of your previous commands. Sure, you can scroll up and down to find the ones you're looking for, but did you know there are faster ways to find what you need as well as handy shortcuts to making use of them.

Tip of the Trade: There are three major ways of invoking bash, all of which behave differently when reading in settings files. The one to pick depends on the scope and implementation of the settings being changed.

By now, it's practically canon that bad passwords can have catastrophic consequences. What can a security admin do to ensure users are doing their part for server security? Enter Medusa, an open source software password auditing tool for Linux that will put all of your organization's passwords to the test.

Tip of the Trade: If you find yourself using the same commands over and over between Vim session, it's time to consider permanently saving your macros.

Tip of the Trade: With GoodReader, iPad meets open source, and files can be shared between the popular tablet and a computer.

Tip of the Trade: The Expect package found in Debian and Ubuntu is a powerful utility that can script interactive operations.

Tip of the Trade: Uuencode is a command-line oneliner that saves you time by piping attachments directly into the mail command.

We've looked at the basic principles behind Windows Server 2008 Directory Services and explained its categorization, which divides preferences into Windows Settings and Control Panel Settings. Now it's time to check out the common options that provide additional functionality and impact settings in both categories.

Tip of the Trade: The value of an opposable thumb is more keenly felt when it can't be used. Fortunately, for programmers who can't leave their keyboards, there are tools to mitigate the problem. Here are two websites to check out should you find yourself in this predicament.

Tip of the Trade: A reader weighs in on the backspace/delete terminal problem. Although the solution doesn't solve the problem at hand, it does lead to some interesting open source software troubleshooting.

Tip of the Trade: VirtualBox makes it easy to set up and run virtual machines on your own desktop. It is not perfect, however, and by default, the guest VM is invisible to the host or any other machines on the network. Here's an easy way to relay instructions to it.

If you've ever had to stop and check the manpage to get the crontab syntax correct for your Unix or Linux server, here's a Web site that will save you lots of time.

If you run a Windows shop, you may think Apache, FreeRADIUS and FreeNAS are off limits. Think again. With a few simple choices, any of these popular open source servers can be deployed in a snap.

Tip of the Trade: With spring in the air outside, why not add some color to your Linux OS powered terminals? Bashish offers a fun and simple way to add themes to your terminal.

Tip of the Trade: Backspace and delete may seem the same, but often they are not. This is particularly problematic when using Screen on OSX Terminal. Here are three easy fixes.

Tip of the Trade: Want to use Grep without including some directories? Here's a simple, yet efficient way, for the open-source software to find what you're looking for.

Tip of the Trade: If you've ever felt the need to scribble notes on your PDFs without bringing dead trees into the equation, consider the open-source software, Okular, a KDE document reader that can read multiple document formats and allows the user to annotate files as she reads.

Tip of the Trade: Bash redirection is tricky. Here's a handy cheat sheet for this open-source software utility.