Ubuntu Tutorials

Skype just recently released an updated version of their desktop client for Linux, Skype Beta v2.1.0.81. This release fixes some major bugs and well as introduces some new features previously unavailable on the Linux release. I am very happy to see this version released as I use Skype quite regularly. Not only to talk to distant family, but also day-to-day as a standard home phone. Yes, that’s right. It is 2010 and I don’t even own a cell-phone! With high-speed internet so readily available between my home, office and public transportation, I simply use Skype as my contact phone number.

In this article I will outline how to install the latest Skype release directly from the Skype website. This version should fix the issues Ubuntu users previously had with Pulse Audio as well as issues presented by using dark themes in GNOME.

Requirements

If you currently have Skype installed, from the Medibuntu repository, you’ll want to remove that package. Until the Medibuntu team updates their release, the two packages might conflict.

You can uninstall the existing package using the command:

sudo aptitude remove skype

Installation

We’ll now grab the Skype for Linux Beta v2.1.0.81 package from the Skype website. The links below are direct-download links. Please select the appropriate architecture:

• Skype for Linux Beta – 32bit
• Skype for Linux Beta – 64bit

Once the package downloads you should be prompted to either “Save As…” or “Open With : GDebi Package Manager”. Select the latter which will launch a package management tool and install the package for you. If you are only prompted to “Save As”, you can simply double-click on the Skype download item in your Downloads window and the installer will launch.

If there are any needed dependencies these will be taken care of using this tool.

Applying GNOME Theme

This release now allows you to apply your GTK theme to the Skype desktop client. You can do this by launching Skype (Applications > Internet > Skype) and opening the “Options” menu. On the General tab you can now select “Choose Style” underneath the language selection option. This will allow your Skype client to better blend in with your GNOME Desktop.

New Features
This release of Skype includes a number of new features other than the bug fixes mentioned above. Some of these new features have been available on the OS X and Windows version, but are now also included in Linux. These include:

• Screen Sharing
• Report Abuse
• Support for UI Styles
• Message Quoting
• Localized Time Formats

See the Skype Changelog for more detailed information.

Conclusion
Skype is a great tool for communicating with friends and family worldwide. It has become a required tool in my daily arsenal, and I think these new additions make it even better. If you haven’t used Skype in a while, I’d invite you to check out this release.

If this article has been helpful, please consider linking to it.

I know many people are curious regarding which Ubuntu kernel is available, and how the kernels differ between distributions. I thought it would be interesting to create a reference outlining each of the supported and available kernels on Ubuntu, and which release they correspond to. I will try to keep this page updated with the latest information regarding Ubuntu kernel versions, including:

• Ubuntu Release (supported releases only)
• Kernel Version (including main and updates)
• Installation / Upgrade Instructions (how to install a specific kernel)

I hope this ends up becoming a useful quick reference for the community.

Ubuntu Kernel Versions

I’ve included a screenshot of the initial data. Please note that this screenshot is not kept up to date. Please download the latest PDF linked below.

Download the latest .pdf here.

I had a request the other day at the Utah Open Source Conference to share a very small script that I have that checks for, and reports any available updates on a YUM based machine. This means CentOS, RHEL, Fedora, etc. I have been using this script at work for some time now and, by placing it in the /etc/cron.weekly/ directory, it reports to me on what packages are available for update. I find this to be a simpler solution than manually checking and trying to keep on top of all of my machines all the time.

I have outlined two revisions of this script below. The first one has properly formatted reports, the second one only reports if there are available updates. I would like to combine the functionality, but I’ve only briefly looked at doing so.. and I don’t feel like doing it now.

If anyone has any other solutions, or perhaps an official program with the same functionality I’d love to hear about it.

/etc/cron.weekly/check-update.sh – revision #1

#!/bin/bash
#
# Weekly check-update report
#
usr/bin/yum check-update > /tmp/.check-update
cat /tmp/.check-update | mail -s "Errata Report for $(hostname)" admin@example.com

/etc/cron.weekly/check-update.sh – revision #2

#!/bin/bash
#
# Weekly check-update report
#
MESSAGE=$(/usr/bin/yum check-update)
if [ $? -eq 100 ]; then
echo ${MESSAGE} | mail -s "Errata Report for $(hostname)" admin@example.com
fi


I presented earlier today at the Utah Open Source Conference and briefly demoed some of the use cases for screen. During the presentation I had a number of requests for my .screenrc file, so I thought I would attach it here. If you use screen for any reason you might find this useful.

Download

## general tweaks
vbell off
autodetach on
startup_message off
defscrollback 1000
attrcolor b ".I"
termcap xterm 'Co#256:AB=\E[48;5;%dm:AF=\E[38;5;%dm'
defbce "on"
#term screen-256color

## apps I want to auto-launch
#screen -t irssi irssi
#screen -t mutt mutt

## statusline, customized. (should be one-line)
hardstatus alwayslastline '%{gk}[ %{G}%H %{g}][%= %{wk}%?%-Lw%?%{=b kR}[%{W}%n%f %t%?(%u)%?%{=b kR}]%{= kw}%?%+Lw%?%?%= %{g}][%{Y}%l%{g}]%{=b C}[ %D %m/%d %C%a ]%{W}'


After getting a lot of feedback from the crowd regarding window managers I’ve decided to try a few out. Initially I’ve tried awesome and wmii, and I’m fairly impressed with both. I do wish I could combine some of the features that I like from each one–and maybe that is possible. Below are my thoughts on each:

awesome
This window manager seems like it is very actively developed and has a decent following. It has a lot of features that I haven’t even looked at yet, but for basic window management it works well. It has a decent default configuration and is easy to navigate once you familiarize yourself with the keys.

I like the pre-defined layouts that you can toggle through with mod-space. This allows you to really easily toggle between vertical, horizontal and many more layouts without a lot of work.

I also like that the configuration is so simple. I really haven’t found a need to change much (yet), but the lua based config is very readable from what I’ve seen.

wmii

This window manager seems just as minimal as awesome, and even has a few things that I like that I didn’t find in awesome. The only immediate difference in wmii and awesome is the mod key is different (alt on wmii, super on awesome). wmii also swaps the status bar to the bottom vs the top and only displays the space/tag if there are open applications.

I like the dmenu (alt-a) as well as alt-p. I find the auto-find of dmenu a little more dynamic than the super-r ‘run dialog’ of awesome. This is one of the things I like most about wmii vs awesome.

It seems to be easier to arrange windows in different layouts in awesome than it is in wmii, but it is possible just the same.

At the end of the day my machine is still running wmii, but I’m yet undecided. Can anyone offer more tips on usage, scripts, plugins, etc of either?

If you spend any amount of time in a terminal you very likely end up needing to use a text editor. Text editors can be very powerful tools, and therein introduces the age-old editor wars. Vim vs Emacs, etc. No matter what your preferred editor is, it helps if it is the default. It is always a pain to be presented with an editor you’re not used to when trying to configure your system. This short article will outline how to change the default editor for your system, ensuring you’re always presented with your preference.

Alternatives

Linux provides a system tool called alternatives, which allows us to have multiple tools installed that each provide the same functionality. Using this tool we can tell the system which one we would like to use as the default, leaving the others available but not primary. To use the alternatives tool to change your default editor, use the command:

sudo update-alternatives –-config editor

You should be presented with a menu similar to this:


There are 4 alternatives which provide `editor'.
Selection    Alternative
-----------------------------------------------
1    /usr/bin/vim.tiny
2    /bin/ed
3    /bin/nano
*+        4    /usr/bin/vim.gnome
Press enter to keep the default[*], or type selection number:


Your options may vary depending on which editors you have installed. No matter what your options are, simply select the number you would like to use and your default editor is updated.

To test these new changes use a command that will call the default editor such as visudo or crontab -e.

I setup the new office printer here on my laptop this morning and I had all kinds of trouble getting it to work with the system-config-printer graphical utility that I usually love so much.  As part of my troubleshooting I thought I’d try the web interface, which worked great!  That gave me the idea of sharing how to configure your printers over the default-installed, yet often unused, web interface.

CUPS, the Common Unix Printing System, comes with a web interface by default that many people don’t know about.  If you’d like to take a quick peek at it go ahead and open a new tab and visit http://localhost:631.  Did you know you can configure everything via the web interface that you might normally configure via the graphical interface?  Everything from creating and deleting printers, to printing test pages and assigning the default printer for the machine.

Now, for those of you that are suddenly worried about a service running on your machine that you were unaware of, CUPS only allows connections on the localhost interface by default.  In other words, if you tried accessing it over your public IP it would deny you access.  This means it would also deny access to anyone else trying to get in and manipulate your printers.

It is possible to make this interface open to more than just your localhost connection, just be sure you’re aware of the security implications first.  Anyone with access to that web management tool may be able to view, customize and possibly even delete your configured printers.

To allow access to the printer web interface simply edit the /etc/cups/cupsd.conf file and update the line reading:

Listen localhost:631


To:

Listen 0.0.0.0:631

You can, of course, replace 0.0.0.0 with a more specific IP address. Using 0.0.0.0 will listen on all available addresses the machine has.

In conclusion, configuring your printers is not limited to the graphical interface. CUPS has provided a web interface for some time now and its nearly as simple to use. The next time you have issues configuring or managing your printers, give the web interface a try!

I spent a little bit of time trying to find an answer to this today but I was unsuccessful. I’m hoping one of you will have the secret for me.

Situation:
I’ve configured my .ssh/config file with profile and port information for the many servers I connect to on a regular basis.

Problem:
One of the servers I need to access requires bouncing through another server first. ie; In order to access machine2 I have to connect to machine1 first. How to automate this within the .ssh/config?

When I manually connect to this I use:

ssh -t machine1 ssh machine2

What I would like to do is configure my .ssh/config file to use that -t option when connecting to that specific machine. I would like to be able to simple run:

ssh machine1

and based on the configuration in the .ssh/config have this automatically connect to machine2.

Any ideas?

It has been some time since I’ve done a Vim Tip of the Week, but I came across something today that I thought I would share.  This tip will allow you to use Vim, with all its syntax highlighting glory, as a pager (similar to less or more).

If you use cat or less or more regularly to quickly view files, but you’d like to keep the same syntax highlighting that you’d get in Vim you can use an included config that makes Vim act as a pager.  Setup the following within your .bashrc file, or wherever you keep your shell aliases:

alias vless='vim -u /usr/share/vim/vim71/macros/less.vim'

You’ll then need to re-read that file, which can be done using:

. .bashrc

At this point you can use vless to view a file, which will use the beloved syntax highlighting.  Normal pager shortcuts should work.  q to quit, / to search, pg-up, pg-dn, etc.

Today, considering it is a holiday here in the US, I figured I’d take a day off from the tutorials and ask a question of you.

All of my servers run logwatch (which will make for a great tutorial coming up soon), and I pretty regularly see something like this in the daily output:

--------------------- Kernel Begin ------------------------

1 Time(s): TCP: Treason uncloaked! Peer XXX.XX.XX.XXX:XXXX/XX shrinks window 1898670412:1898670413. Repaired.
1 Time(s): TCP: Treason uncloaked! Peer XXX.XX.XX.XXX:XXXX/XX shrinks window 1911943385:1911943386. Repaired.
1 Time(s): TCP: Treason uncloaked! Peer XXX.XX.XX.XXX:XXXX/XX shrinks window 1922304386:1922304387. Repaired.
1 Time(s): TCP: Treason uncloaked! Peer XXX.XX.XX.XXX:XXXX/XX shrinks window 1922444120:1922444121. Repaired.
1 Time(s): TCP: Treason uncloaked! Peer XXX.XX.XX.XXX:XXXX/XX shrinks window 1949802160:1949802161. Repaired.

———————- Kernel End ————————-

I’m not really sure what that means, but if anyone can offer me some feedback I’d appreciate it.  So far I’ve seen conflicting answers from basic Googling.