One of the things that Linux.com offers to the community is the opportunity to post on Linux.com community blogs. Because it's been a while since we promoted this feature, I wanted to post a reminder about how to post to your blog, and how they're approved. This weekend, let's look at how you can show off your Linux and open source expertise for the Linux.com audience.

Fri, 09 Sep 2011 19:17:42 +0000

WordPress is the leading open source blogging platform for good reasons, but what do you do when the written word no longer suffices? Sure, you can attach an audio or video file to a WordPress post, but if you are interested in managing a professional-caliber podcast from your server, you need more. Let's compare the alternatives.

Thu, 08 Sep 2011 19:57:09 +0000

Vim mastery is not something that you acquire all at once. In fact, it's more something that you slowly sneak up on. Bits at a time, you learn something new about Vim you didn't know it could do. Or you'll figure out an easier way to do something. Such is the case with using the system clipboard on Linux, at least for me.

Wed, 07 Sep 2011 18:48:48 +0000

Linux is a superior audio production platform, and one of its shining stars is the Hydrogen Drum Machine. Hydrogen is an advanced software drum synthesizer that is easy to learn, and yet packed full of great features.

Tue, 06 Sep 2011 17:49:30 +0000

Ever had a Web project in mind, but got stalled at the prospect of having to worry about the site design? If code, and not design, is your strong point you'll want to take a look at Twitter's Bootstrap. This weekend, you can prettify an existing Web site or start a Web project you've been putting off with a full design toolkit.

Fri, 02 Sep 2011 17:11:54 +0000

No matter how slick Linux on the desktop gets, there will probably always be a gulf between new users and veterans for whom the Linux environment has become second nature. Root accounts, the filesystem hierarchy, the dizzying array of distributions — they seem strange at first, but eventually new users learn that are nothing to be feared. So too with the "programmer's editors" Emacs and Vi/Vim: the first encounter can be intimidating because of the unfamiliarity of either editor. As an Emacs user, I'm interested in providing some advocacy, so if you've been wondering just what the point of an editor like Emacs is, or if you're not sure how to get started, read on for a gentle introduction.

Thu, 01 Sep 2011 15:47:18 +0000

Thought you'd be living in a Microsoft Office-free world by 2011? Unless you're in a Linux-only shop that does business only with other Linux-only shops, the chances are that dream remains a few years away, and you still have to drag out an office file converter periodically. The trouble is, each free software office suite has its own, and they vary in their capabilities. Enter DocVert, a worthy GPLv3-licensed utility to keep at the ready, thanks to its choice of CLI- and Web-based interface options, and its flexible output formatting.

Tue, 30 Aug 2011 21:22:56 +0000

This tutorial shows how you can install and run a WordPress blog on a Debian Squeeze or Ubuntu 11.04 system that has nginx installed instead of Apache (LEMP = Linux + nginx (promounced "engine x") + MySQL + PHP). In addition...

Tue, 30 Aug 2011 10:05:14 +0000

The Firefox 6 browser and Thunderbird 6 email app are both out now, and if it seems like just yesterday that you were reading about Firefox 5 — no, it's not your imagination. Both releases are part of Mozilla's new rapid release strategy, which means there are fewer new features in each version, but hopefully less breakage as well. In this case, Web developers get some new tools on the browser front, but Mozilla still has major problems to iron out of the new release approach.

Mon, 29 Aug 2011 18:04:56 +0000

As a writer of fiction, one of the tools I use to help promote my books is the podcast. I admit that my go-to tool for podcasting (along with a really good mic) is Audacity. But I am always in search of newer and possibly better tools for the trade. One application I have found for podcast recording is Traverso.

Fri, 26 Aug 2011 18:15:31 +0000

Google Chrome is not only the fastest loading and rendering browser available, it's also grabbing market share the fastest. And like all good browsers, Chrome offers thousands upon thousands of extensions that can be added to expand the functionality and fun of the browsing experience. Problem is, with so many extensions available, it's hard to know which ones are of the most interest to certain user groups. So, I took the time to dig through the piles to find what I thought to be the best collection of available Chrome extensions for Linux users. So, without further ado, let's get on with the list.

Wed, 24 Aug 2011 19:16:01 +0000

Poseidon Linux is designed for the international scientific community, bundling a big batch of science-oriented software into a single live DVD, plus a batch of desktop productivity and multimedia applications. Poseidon 4.0 was just released with significant changes, so let's take it for a test drive.

Tue, 23 Aug 2011 18:38:09 +0000

Where is the Linux desktop going, and where should it go? This is a hot topic, and an important one. Unfortunately the discussion usually starts from the wrong premise, that the Linux desktop has only recently achieved parity with its Mac OS X and Windows cousins. Not so! The Linux desktop has been superior since its early days, and would have to go backwards to achieve parity.

Mon, 15 Aug 2011 06:54:45 +0000

Installing Nginx With PHP5 (And PHP-FPM) And MySQL Support On CentOS 6.0 Nginx (pronounced "engine x") is a free, open-source, high-performance HTTP server. Nginx is known for its stability, rich feature set, simple configuration, and low resource consumption. This tutorial shows how you can install Nginx on a CentOS 6.0...

Mon, 15 Aug 2011 06:00:00 +0000

Mozilla Thunderbird has earned its place as an email app on Linux desktops, and its cross-platform nature makes it a popular choice for Windows and OS X machines as well — particularly when you include the calendaring and task management power of the Lightning add-on. But uptake in corporate environments has never been its strong suit, largely because it does not include groupware features such as event invitations and shared address books. The SOGo Connector extension adds those features and more, turning Thunderbird into a proper groupware client suitable for business use.

Fri, 12 Aug 2011 18:53:47 +0000

The open source raw photo editor RawTherapee released version 3.0 at the end of July, with a revamped interface and a new palette of photo tools. RawTherapee is noteworthy for several reasons, including the fact that builds are available for Mac OS X and Windows, in addition to Linux. But this release also marks the first major update to the program since it was made free software. Let's take a look.

Thu, 11 Aug 2011 18:56:12 +0000

As Linux continues to re-define its role in the mobile and cloud sectors, there is still demand for using the operating system on "traditional" platforms like the personal desktop, the enterprise server, and even laptop devices. With so many Linux distributions available, which one is the best for each of these varied platforms?

Wed, 10 Aug 2011 19:14:18 +0000

GNU grep is one of my go-to tools on any Linux box. But grep isn't the only tool in town. If you want to try something a bit different, check out glark a grep alternative that might might be better in some situations.

Tue, 09 Aug 2011 17:25:01 +0000

One question we get a lot: What are the best community server distributions? That question isn't as simple as it sounds. What makes a distro "the best"? Why community distributions, specifically? It's not a simple question — but read on and we'll point you to six distros that will help you reach a satisfying answer.

Mon, 08 Aug 2011 16:21:37 +0000

One of the keys to using GNU sed successfully is knowing how to use its regular expressions. If you look over sed scripts without knowing regular expressions, the effect can be pretty disconcerting. Don't worry — it's not as confusing as it looks. This weekend, spend some time with GNU sed's regular expressions and put some real power into your text processing.

Fri, 05 Aug 2011 14:52:38 +0000

Running a open source CMS like WordPress on your own LAMP server is supposed to give you the freedom to develop a better system than you would get from pre-packaged blogging services. Yet a lot of WordPress users effectively outsource their site's discussions by installing closed commenting systems like Disqus or IntenseDebate. In addition to handing someone else the keys to your community interaction, these third-party services can also be slow to load and respond to updates. Let's look at the open source alternatives.

Thu, 04 Aug 2011 19:33:44 +0000

The GNU Image Manipulation Program (GIMP) is one of the most powerful image editing tools available. It is, effectively, the Photoshop of the open source world; and with that kind of title comes a level of power most never take advantage of. One feature that should be a must-use for all digital artists is the layer. Using layers not only makes work easier, it gives digital art more depth and more flexibility.

Wed, 03 Aug 2011 19:21:19 +0000

There is a new Linux on the block and its name is Jeoss. What's Jeoss? It's a compact, install-everywhere Ubuntu-based server distribution. Does the world need yet another Ubuntu derivative? Sure, why not? Let's install Jeoss and kick its tires.

Tue, 02 Aug 2011 16:26:25 +0000

It was big news when the 3.0 kernel was released at the end of July, but as luck would have it, another fundamental piece of your average distribution is about to bump its own version number up to 3.0 as well: the filesystem hierarchy standard (FHS). If you're not sure exactly what that means or why you should care, don't worry. It's the distros that implement the FHS — when it goes well, all you know is that your system runs smoothly. But that doesn't mean there's nothing important hidden away in this new release.

Mon, 01 Aug 2011 13:39:42 +0000

If you've ever needed to edit one or more files to make quick changes, you've no doubt found that doing it using a text editor can be a slow slogging process. Linux, thankfully, has a number of tools that make it easy to do this non-interactively. One of the best is sed, a "stream editor" that can help you make quick work of filtering and transforming text. This weekend, take a few minutes to introduce yourself to sed.

Fri, 29 Jul 2011 14:26:48 +0000

There are three superior Linux/FOSS stargazing applications: KStars, Celestia, and Stellarium. Each one is crammed full of pretty eye candy and scientific goodness, and each one is distinctly different. You don't have to pick just one, so I recommend trying all three.

Thu, 28 Jul 2011 18:32:10 +0000

Mozilla launched its BrowserID project in June as an alternative to the now commonplace practice of relying on third-party commercial Web services as "identity brokers." If you want to offer users a non-intrusive way to establish an identity, without the overhead and security worries of an awkward off-site authorization process, it is worth taking a look.

Wed, 27 Jul 2011 19:31:30 +0000

Looking for Linux games? On a tight budget? Want to support "indie" developers? Then you should take a look at the Humble Indie Bundle #3 that's on sale for two more weeks. Did we mention that Linux users are putting up twice as much money on average than Mac users, or three times the average for Mac users?

Tue, 26 Jul 2011 20:12:28 +0000

This may not be the year of the Linux desktop, but don't tell that to ZaReason. The folks at ZaReason have, once again, outdone themselves with a high-quality and powerful 15" laptop that will satisfy power users and Linux gamers. Let's take a look at the Verix 2 with Ubuntu 11.04 and see what it has to offer.

Mon, 25 Jul 2011 15:29:18 +0000

For the security conscious, there is always room for another weapon against attackers. Firewalls, intrusion detection systems, packet sniffers — all are important pieces of the puzzle. So too is Honeyd, the "honeypot daemon." Honeyd simulates the existence of an array of server and client machines on your network, including typical traffic between them. The phantom machines can be configured to mimic the signature and behavior of real operating systems, which will trick intruders into poking at them — and revealing themselves to your security staff.

Fri, 22 Jul 2011 18:13:12 +0000

Oracle released VirtualBox 4.1 on July 19 with a slew of improvements ranging from usability improvements to rasing the ceiling for RAM to 1TB for 64-bit hosts. With 4.1, we decided to take VirtualBox out for a spin and see how it handles.

Thu, 21 Jul 2011 19:01:13 +0000

Where was that page you were just looking at a few days ago? If you're a Firefox user, answering that question just got a lot simpler. Yes, the browser offers simple bookmarking and niceties like bookmark folders and multi-browser sync — and yes, there are hundreds of add-ons to help you categorize, tag, export, import, and file your links in every conceivable way. But all too often, re-finding that page you just took a casual look at is still easier to do with a Web search engine — and that's the premise behind RecallMonkey, which gives you a search-engine-like interface to your own browsing history.

Wed, 20 Jul 2011 18:49:22 +0000


Are you still taking screenshots? That is sooo last decade. Today if you want to showcase your application, your gaming skills, or even your astonishing new desktop wallpaper collection, you need a screen recorder (or screencasting tool) to capture full-motion video and audio of your desktop. You'll find several solid options, but which one works best for you depends a lot on the type of content you need to capture, and what you intend to do with it.

Mon, 18 Jul 2011 17:35:29 +0000

Tired of automated attacks on your systems? Want to beef up security a bit by denying would-be attackers a third or fourth chance? Then you need Fail2ban. Fail2ban watches logs and then bans IP addresses, based on too many password failures, by updating the firewall rules. Specific rules can be defined by the user and multiple log files can be monitored. This weekend, let's get started on improving security with Fail2ban.

Fri, 15 Jul 2011 19:21:00 +0000

Though netbooks have waned a bit in favor of tablet devices, there's still a lot of demand for netbooks and netbook-friendly Linux distros in certain circles. Whether you're looking for a brand-new netbook or to keep an older device current, there's plenty of options for the Linux crowd. Let's take a look at the top five netbook Linux distros.

Thu, 14 Jul 2011 17:31:14 +0000

Fluxbox is a fast, lightweight, very customizable window manager for X. Fluxbox is a great choice for Linux users who favor speed and efficiency, and setting up their working environment just the way they like. Today we'll look at some super-saver speed tricks such as grouping applications with tabs, tear-off menus, sticky buttons, the infamous slit, and more.

Tue, 12 Jul 2011 15:22:37 +0000

In the quest to find the perfect Linux distribution, we often hit an obstacle that makes the grass look greener on another distro's lawn. When we reach that point, the first instinct is to turn to another distribution and hope that something fresh will also be something better. This time around, I decided to see if PCLinuxOS was indeed greener.

Mon, 11 Jul 2011 16:35:16 +0000

Thunderbird got a big boost recently with the news that Ubuntu will be using it as the default mail client in Ubuntu 11.10. If you're getting ready to switch to Thunderbird, or just want to spruce it up a bit, here's a few extensions that will make Thunderbird 5 even more useful.

Fri, 08 Jul 2011 17:36:30 +0000

While many of us were barbecuing and blowing things up, the WordPress folks were putting the finishing touches on WordPress 3.2. On July 4, the "faster and lighter," WordPress 3.2 was released with some features well worth checking out.

Thu, 07 Jul 2011 19:36:46 +0000

PiTiVi is a GStreamer-based non-linear video editor (NLE) developed by members of the GStreamer project itself. That means it is often the first project to showcase new features, and last month's new release is no exception. The major new feature is support for audio and video filter "effects" but there are usability and speed improvements worth examining, too.

Wed, 06 Jul 2011 17:20:57 +0000

Apache is very flexible, and it's easy to configure Apache to handle several domains even when your Web server only has one IP address to share between them. You can use this to host multiple sites, or just to provide a sandbox for development rather than making changes on your live site. This weekend, we'll learn how to create virtual hosts with Apache.

Fri, 01 Jul 2011 16:32:27 +0000

The FreeNAS distribution is tailor-made for installation in a small office environment. It is an extremely low-resource network storage system that you can administer through a Web browser, but it supports high-end features like automatic backups, replication, LDAP or Active Directory authentication, and seamless file-sharing over NFS, CIFS, AFP, and even FTP and TFTP. The latest release — version 8.0 — is just a few weeks old, and it is the perfect time to take a look.

Thu, 30 Jun 2011 06:00:00 +0000

What do you get when you combine Firefox and Pidgin? No, it's not the setup to a geeky joke (yet) — it's Instantbird, an instant messaging client based on Firefox with Pidgin's libraries providing the protocol support for IM networks. With the 1.0 release just out the door, let's take a look at Instantbird and how it measures up.

Wed, 29 Jun 2011 16:48:38 +0000

Getting a screen shot should be easy, shouldn't it? On Android, not so much. While it's trivial to get screenshots on the Linux desktop and on some other mobile platforms, Android is a different story. If you need or want to get Android shots, without rooting your device, you can — using the Android SDK. Here's how, in as few steps as possible.

Mon, 27 Jun 2011 17:48:36 +0000

DNS Service Discovery (DNS-SD) is a component of Zeroconf networking, which allows servers and clients on an IP network to exchange their location and access details around the LAN without requiring any central configuration. Most Linux distributions supply the Avahi library for Zeroconf support, but not nearly as many users take advantage of it. Let's look at an easy-to-set-up use for DNS-SD: providing automatic bookmarks to services. All it takes is an Apache module and a Firefox extension.

Fri, 24 Jun 2011 19:32:04 +0000

In the never-ending quest for task-management software, most Linux users gravitate towards fancy GUIs, multi-faceted import/export, and endless customization. Sadly, all that achieves is a cornucopia of incompatible GUI to-do managers, and when one goes dormant, the others are no help. But if you take the "less is more" approach instead, you'll find todo.txt a worthy alternative. Todo.txt stores its data in a flat text file that any application can read, but it gives you full access from the command line as well as from Android and other mobile devices.

Thu, 23 Jun 2011 16:40:51 +0000

Picking a Linux distribution isn't always easy. It's one of the most common hurdles for new and aspiring Linux users, deciding which distribution is going to be right for them. With so many to choose from, how do you pick the right one? Let's start with an overview of the major Linux distros, and you'll be ready to jump in right away.

Wed, 22 Jun 2011 18:33:35 +0000

If it seems like Mozilla just released a new version of Firefox, that's because they just did. Just back in March, as a matter of fact. If you're used to the long waits between Firefox releases — and inevitable schedule slips — those days are behind you. The Mozilla folks are now focusing on faster Firefox releases, with fewer features per release but a more steady cadence of updates.

Tue, 21 Jun 2011 18:16:02 +0000

If you've set up an OpenVPN server to provide secure access to remote workers, you've got half the battle won. The next step is to get your users' (or your) systems ready to connect back to the mothership. Don't worry, it's easy to get Linux set up to connect to an OpenVPN server, it just takes a few steps.

Although not as easy as a point and click GUI, the OpenVPN Client is not all that challenging to configure and start up. That will be the primary focus of this article; but, for good measure, we'll add mention of a few good GUI tools that can also handle the task. For information on how to set up the OpenVPN server, check out the previous installment, "Install and Configure OpenVPN Server on Linux."

Installation

It is necessary to install OpenVPN on the client. The package to be installed is, as expected, openvpn. To install on Ubuntu, follow these easy steps:

  1. Open up a terminal window.
  2. Run sudo apt-get install openvpn.
  3. Type the sudo password and hit Enter.
  4. Accept any dependencies necessary and allow the install to complete.

Believe it or not, that's it for the installation of OpenVPN.

Configuration of the Client

As discussed in the previous article, there will have been certificates created (on the server) specifically for the client machine. The files that need to be securely copied to the client's /etc/openvpn directory are:

  • /etc/openvpn/ca.crt
  • /etc/openvpn/ta.key
  • /etc/openvpn/easy-rsa/keys/hostname.crt (Where hostname is the hostname of the client).
  • /etc/openvpn/easy-rsa/keys/hostname.key (Where hostname is the hostname of the client).

Copy those files over using a tool like scp from the server to the client. If the server doesn't have direct access to the client, just put them on a flash drive and copy from there.

The first step in the configuration of the client is to copy the sample client configuration file to the proper directory with the command sudo cp /usr/share/doc/openvpn/examples/sample-config-files/client.conf /etc/openvpn. With that file in place, it's time to make a few edits. Open up /etc/openvpn/client.conf with a text editor (such as Nano or vi) and take a look at the following section:


dev tap
remote vpn.example.com 1194
cert hostname.crt
key hostname.key
tls-auth ta.key 1

Make the changes where:

  • vpn.example.com is the address to the OpenVPN server.
  • 1194 is the port configured on the OpenVPN server.
  • hostname.* is the actual name of the certificate and keyfile names.

Believe it or not, that's it. The only step that is remaining is to restart OpenVPN with the command sudo /etc/init.d/openvpn restart. Once this service has restarted, the remote LAN should be accessible. Test to make sure by pinging a known address on the LAN behind the VPN.

GUI Tools for Connecting to OpenVPN

Both KDE and GNOME offer plugins for their network manager applets that allow VPN connection to an OpenVPN server. The necessary plugins are:

  • KDE: network-manager-openvpn-kde
  • GNOME: network-manager-openvpn-gnome

More than likely, those plugins will not be installed on the distribution by default. A quick search using the Add/Remove Software utility will allow for the installation of either plugin. Once installed, the use of the network manager applets is quite simple, just follow these steps (I will demonstrate using the KDE network manager applet):

  1. Open up the network manager applet by clicking on the network icon in the notification area (aka System Tray.)
  2. Click on the Manage Connections button.
  3. Select the VPN tab.
  4. Click the Add button to open up the VPN type drop-down.
  5. Select OpenVPN from the list.
  6. Fill out the necessary information on the OpenVPN tab (Connection Name, Gateway, Connection Type, certificate file locations) See Figure 1 for an illustration of this tab.
  7. If a static IP address is necessary then set that by selecting Manual from the Method drop-down (in the IP Address tab).
  8. Click OK to save the settings and dismiss the Connection Settings window.

Figure 1If this client is to always be connected, the Connect Automatically check box can be checked.

Now, to connect to the OpenVPN server, using the KDE network manager applet, do the following:

  1. Click on the network manager applet.
  2. Click on the Virtual Private Networking button from the popup menu.
  3. Select the newly created OpenVPN connection.
  4. Allow the connection to negotiate authentication.

Once the authentication has been negotiated, the VPN connection will be listed as Connected in the network management applet. The VPN LAN should now be accessible.

Gadmin OpenVPN Client

If an alternative desktop is in use, or either KDE or GNOME's network manager tool doesn't fit the bill, there is another tool that does a great job of connecting to an OpenVPN server. That tool is Gadmin OpenVPN Client. This tool can easily be installed from within Synaptic, Ubuntu Software Center, PackageKit, and more. Once installed it's just a matter of firing up the tool (if it can not be found within the menu structure of your desktop, Gadmin OpenVPN Client can be started with the command sudo gadmin-openvpn-client.)

When the tool opens the first thing that needs to be done is the information for the connection must be filled in (see Figure 2).

Figure 2Don't hit the Add button first!

Make sure to scroll down and fill in all of the necessary information, which includes:

  • Connection name: Human readable name for the connection.
  • Server address: Address of OpenVPN server.
  • Server port: The port configured on the server.
  • CA cert/Cert/Key/DH Key/TA key: Location of the certificates generated on the server and then placed on the client. This configuration is all the way at the bottom of the config screen.

After all of this is configured, click the Add button and the connection will then be added. To bring up the connection, select the VPN connection to use and then click the Activate button, which will start the process of certificate negotiation. After the negotiation process is complete, the VPN Network should be available.

As expected, there are plenty of ways to connect to an OpenVPN server. And although not nearly an exhaustive resource (there are more GUI tools to be found in your Add/Remove Software tool), with the above tutorial helping out, a connection can be made from both from the command line and from a GUI. Note that if you've got users on Windows and Mac, the OpenVPN folks also have clients for them.

Mon, 20 Jun 2011 18:39:30 +0000

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