Ubuntu Tutorials

Sponsored by the GNOME Foundation

We’ve been working hard on the list we’ve assigned ourselves in the GNOME Sysadmin Hackfest. So far we’ve made a large number of commits to our puppet configuration tree, as well as got two new servers installed. A large number of our web services are now migrated to a new RHEL6 based web server, which is running smoothly. This is a great step toward being able to migrate everything onto supported, high performance hardware.

While Olav Vitters wasn’t able to physically attend the Hackfest he has been making some impressive contributions to the project and the TODO list we’ve compiled. I want to put out a big thank you to him for all his contribution!

I’ve made a number of improvements to the Nagios monitoring solution, expanding it to include the new virtual machines and tweaking the sensitivity of some of the checks. In addition, I’ve written a new nfs client and nfs server puppet class, which should allow us to more easily configure our NFS shares, which we use quite a bit of.

We’ll have more to report as the conference continues. I think we’re going to have a very impressive overall report  by the time this is all over.

Sponsored by the GNOME Foundation

Today I’m at SCALE in Las Angeles. I’m here for a few reasons, including as a Speaker on Sunday morning, to help manage the GNOME Foundation exhibition booth, and to participate in the GNOME Sysadmin Hackfest.

As the staff GNOME Sysadmin I proposed and planned a Sysadmin Hackfest that would allow us to work on some of the core infrastructure improvements that would benefit from face-to-face collaboration.

A lot of the things that we’ll be working on are behind the scenes, but they’ll have a long-term positive effect for the Foundation and the development teams.

Unfortunately, a lot of the hardware that the GNOME Foundation has been working with is now outdated and out of warranty. This leaves us in a difficult situation in the event of an outage or hardware failure. This will be remedied during this hackfest! The GNOME Foundation has approved and ordered two new nice Dell servers. The new Dell R610 is now setup and ready to buildout. This machine will be the new NFS server as well as a container for new RHEL6 virtual machines. We’ll be able to migrate a large majority of the dated hardware into up to date virtual machines. We’re all very excited about this!

We’re also dedicating time to address a number of the long standing bugzilla issues. This includes a number of improvements to the user management system. We use this system to track and manage access controls, foundation membership, email and SSH key configuration and deployment and other related tasks.

I’ll post updates throughout the weekend on our progress and maybe, if you ask nice enough, we might just have a look at one of your bugs!

This morning I had a little bit of free time so I thought I’d (finally) check out the Firefox extension Firesheep. The main website mentions that it isn’t supported for Linux, but the source code is available and as it turns out very easy to compile. Below are instructions for downloading, compiling and installing the Firesheep security plugin for Firefox.

Get the Source

You’ll need to download the source code from github, which can be done using the following two commands:

git clone https://github.com/codebutler/firesheep.git
cd firesheep
git submodule update --init

These two commands will download the code required to compile Firesheep, putting the source into a new directory called “firesheep”.

Build Tools

To compile Firesheep on Ubuntu 10.04 or 10.10 you’ll need the following development packages installed. Simply copy-paste the following list of packages into your terminal:

sudo apt-get install autoconf libtool libpcap-dev libboost-all-dev libhal-dev xulrunner-1.9.2-dev

On my machine this installed quite a few packages, and while the main Firesheep website lists 10.10 specifically, I had no problems on my 10.04 installation.

Build Firesheep

You’re now ready to compile Firesheep. Run the following command and hopefully you’ll be able to build it without error:

./autogen.sh && make


Install the Plugin

If all is well you should find a new file called ‘firesheep.xpi’ in a subdirectory called build (ie; firesheep/build/). Simply drag-and-drop that file into your Addons dialog box, restart Firefox and you should be set.

I’ve been having some issues in actually capturing data on my Dell D630 with an Intel Pro/Wireless 3945ABG card. It looks like this tool is often hardware specific, so your mileage may vary. I’d be interested in anyone offering suggestions on getting it to capture properly on OS X 10.6 (macbook) or Ubuntu 10.04+.

I am happy to announce that GNOME 2.32 has now officially been released! This release is a bit smaller than what you’ve come to expect, but that is simply because most of the focus is on the upcoming GNOME 3.x series! I want to congratulate the entire GNOME team for all of their hard work and for yet another improved and polished release.

Be sure to check out the GNOME 2.32 Release Notes for more details.

I mentioned a week or so ago that I would be having another article published in the near future. I’m happy to announce that the article is now available. I hope you’ll take a few minutes and head over to have a read. If you have any comments, or suggestions on accuracy or improvements please do let me know and I’ll update where necessary.

Ubuntu Server and WordPress in 15 Minutes Flat

This evening I got to thinking about web browsers and privacy. Privacy is, of course, a regular concern for many of us and there are many different “solutions” out there. Recently web browsers have been adding privacy modes, which allow us to browse the web without storing a lot of cookies, history, etc. Google Chrome (or Chromium) provide the “Incognito” mode, which allows for private browsing. This mode can be launched using the key combination “shift-ctrl-n” or selecting “New Incognito Window” from the menu. The only missing piece is until recently there hasn’t been a way to launch this mode by default.

In this article I will outline how to update your system to launch Google Chrome’s Incognito mode by default. This includes launching it from the Applications menu as well as making it the default when opening new links.

Step 1:

Edit your Application menu entry for Google Chrome (or Chromium) using the ‘alacarte’ application. You can launch this command directly or right-click on the Applications menu and “Edit Menu”. Navigate to “Internet” section and select the Google Chrome (or Chromium) entry.

Once selected, simply double-click the item to open its properties and update the command, description or title.

As you can see from the screenshot above, the addition you’ll want to make is the “--incognito” between the existing chromium and %U. This will update the Applications menu, essentially setting Incognito mode as the default when launching this application new.

Step 2:

In addition, if you want links to be opened in Incognito mode you’ll also need to update your Preferred Applications configuration. This is done in the Preferences > Preferred Applications. This is assuming that Google Chrome (or Chromium) is set as your default. In the screenshot below, you’ll see that we’ll essentially make the same change as we did above.

Conclusion

These two simple steps will configure your browser to perpetual private mode. From my searching, I couldn’t find any documentation specific to Linux, so here it is. I hope you find it helpful!

I took some time today to check out Ubuntu 10.10 Beta. So far I’m impressed with some of the improvements, and I’ll blog about those later, but in the meantime I thought I’d share a workaround I came across in getting Guest Additions working when running Ubuntu 10.10 inside VirtualBox.

My first attempt at getting Guest Additions installed was by mounting the CD and running the command:

sudo ./VBoxLinuxAdditions-x86.run

While this attempted to compile the drivers necessary for Guest Additions, it never seemed to work. After repeated reboots and rebuilds, I could never get a better resolution. After a little searching I came across a solution that seems to take care of the problem.

To install Guest Additions in Ubuntu 10.10 Beta, you’ll need to install a pre-packaged version available through the repositories. You can run the command below, or click on the URL:

sudo apt-get install virtualbox-ose-guest-x11

After a quick reboot you should be set.

I hope you enjoy Ubuntu 10.10 Beta (and forward). It’s the little things like this that make testing it in a virtual machine worthwhile.

I know I haven’t been blogging much lately. I’ve been occupied with other responsibilities. Besides work and school I’ve been dedicating a lot of time volunteering on the GNOME Sysadmin team, trying to make sure that it remains a well-oiled development machine! I had a few minutes this evening however and I thought I would give you a heads up on an article I’m waiting to have published.

As some of you know, I have been writing off and on for Packt Publishing‘s online Article Network. I’ve covered a number of Ubuntu related topics such as: “What’s New in Ubuntu 9.10“, “Network Based Ubuntu Installations“, “Ubuntu 9.10: How to Upgrade“, “Creating Local Ubuntu Repositories“, “Five Years of Ubuntu“, “Ubuntu User Interface Tweaks“, “Install GNOME-Shell on Ubuntu 9.10“, “Securely Encrypting Removable Media“, and “Folding @ Home on Ubuntu“.

My latest article, which should be published this week sometime, is a quick-install guide to Ubuntu Server 10.04 toward the goal of a “LAMP” web-server. The article includes screenshots for installing Ubuntu Server, installing the Apache, MySQL and PHP components, and installing a WordPress installation, managed by subversion. It probably sounds like there is quite a bit to it, doesn’t it?

The best part of the article is that you can go from zero to WordPress in fifteen minutes! I’ve timed it. Twice. I setup a virtual machine and by following these instructions I can go from no operating system to a working WordPress installation in under fifteen minutes. It’s really quite amazing! Ubuntu Server is so user friendly, and they’ve put in enough attention to the little details, that really anyone can set up a web server and start publishing content in no time!

I have a follow-up article in the works (still a few weeks out, at least) which outlines expanding your web server to include SSL, virtual hosts (multiple sites), managing and upgrading your WordPress engine using subversion, and more.

I’ll post links when both of these publish. Until then…

Christer

The topic of installing Adobe products in Ubuntu has both been loved and hated by reader since the first time I outlined it. Some very much appreciate the clear steps outlining installation of the PDF reader application. Others despise the idea of proprietary software intermingling with their otherwise open source desktop. However you feel about Adobe Reader, love it or hate it, it is a popular application and in many cases required by users for work or otherwise. With each new Ubuntu release I outline how to install and update your Adobe Reader installation.

Repository Requirements (Optional)

Canonical, the parent company behind Ubuntu, has provided a repository to distribute Adobe Reader and similar applications. The method of installing Ubuntu by way of a repository is more automated than a direct download from the Adobe website. I’ll outline either version, but keep in mind that I prefer (and suggest!) the first. Configuring the partner repository is a requirement for the first option.

Canonical Partner Repository – Option 1

Installation of Adobe Reader 9 requires the activation of the Canonical Partner repository. You can add the Partner repository by following the steps outlined below.

1. Navigate to System > Administration > Software Sources
2. Select “Third Party” or “Other Software”
3. Select “Add” and enter: deb http://archive.canonical.com/ lucid partner

You should now be able to install the latest version of Adobe Reader on Ubuntu 10.04 LTS by using the following command, or clicking the embedded link:

sudo aptitude install acroread

Direct Download: Adobe.com – Option 2

The alternate installation solution is to download Adobe Reader directly from the Adobe website. As a disclaimer, I should warn you that this method will not receive automatic updates and it is left to the user to download and install any future releases of this application.

If you understand these requirements, continue to install Adobe Reader using the following steps:

1. Visit this page: http://get.adobe.com/reader/otherversions/
2. Select “Linux – x86 (.deb)” from the drop-down menu
3. Select your preferred language
4. Download the package

Depending on your browser you may be prompted to open the package with the package installer, or it will simply save it to disk. If it saves to disk, you’ll simply need to double-click the archive for the installation to begin.

Conclusion

Most of my dealings with PDF files is managed by Evince, the default GNOME pdf reader. Occasionally however I need the Adobe-specific application. As with many of the readers here, I prefer the free software solution where possible, but sometimes it just isn’t possible. Love it or hate it, Adobe Reader is sometimes part of our lives.

Again, I would suggest the first solution toward installing Adobe Reader as it will automatically manage security updates for you. The packages are provided directly from Canonical, Ubuntu’s parent company, and managed by Ubuntu staff. I trust these packages just as much (if not more) than the direct-from-adobe packages available in the secondary solution.

I recently wrote an article outlining how to remove the login screen user list in the KDE login screen. This article outlines the same steps, but specific to the GNOME login screen. The instructions here have been tested on Ubuntu 10.04 LTS as well as Ubuntu 9.10. If you would prefer to remove the user list from your login screen and require the username be entered in combination with the password, these instructions will achieve just that.

GDM Changes

I believe it was with Ubuntu 9.10 that the GDM login manager was rewritten and the previous configuration options removed. I know there was a lot of upset about that when it happened. The functionality seemed to be the same, but the configuration options that users had grown used to were now gone. It seems, however, that there are still some settings that can be changed. Perhaps not quite as many, but one of the important ones is still available. If slightly obscure.

Updating Configuration

There are two methods of updating this configuration. There is the command-line one-liner, which I like for it’s quick and easy use. There is also the graphical method. I’ll outline both below. You can follow whichever you feel most comfortable with.

Command Line : gconftool-2

To disable the login screen user list in Ubuntu 10.04, simply run the following command, entering your password when prompted:

sudo -u gdm gconftool-2 --set --type boolean /apps/gdm/simple-greeter/disable_user_list true

The next time you log in you’ll be prompted to enter your username and password, instead of selecting your username from a list.

Graphical Method : gconf-editor

To disable the login screen user list in Ubuntu 10.04 graphically, run the following command and then navigate to the proper key=value pair setting.

sudo -u gdm gconf-editor

Navigate to /apps/gdm/simple-greeter.

Check the box that says “disable user list”, setting the value to true.

disable ubuntu login user list

Whichever method you choose, you’ll end up with the same result. Disabling the list of users at the login screen. I prefer my machine to require the username + password combination. No reason in telling everyone who the machine belongs to, and removing half of the security of the login mechanism.

I am interested in hearing your thoughts on the security vs usability of a user list at login. Do you agree with me or disagree?