Unfortunately, in the other spirit of open-source, the simple documentation is lacking a bit, so this blog post will hopefully help pave the way for people who might follow in my footsteps.

Intended Use

Basically, within one of the applications, I desired to have a link available in a menu that simply says “Report a problem”, which then submits a prefilled report to a bug tracking system including important information such as which version is being run, OS details etc.  My experience with Ubuntu has taught me that Apport is an ideal system that already supports the intended use-case, and is integrated into some existing apps in the same way that I’m looking for.

UbuntuOne Apport Configuration

The existing documentation that I referenced most heavily was found at https://wiki.ubuntu.com/Apport and https://wiki.ubuntu.com/Apport/DeveloperHowTo.  The first thing that struck me was that there seems to be no simple uses cases for what I thought would have been a reasonably commonly required use case, i.e., how to integrate with an app being released from a launchpad-hosted ppa.  The existing apport configuration makes apport-bug prevent reports being generated for non-Ubuntu packages (i.e., packages that are not in the main Ubuntu repositories).  This creates a hassle if releasing from a private or team ppa.

Fortunately, through browsing /etc/apport/ I found that the ubuntuone-client already uses apport with a non-genuine Ubuntu package.  This is done by placing a config file in /etc/apport/crashdb.conf.d, and an apport hook in /usr/share/apport/package-hooks/source_ubuntuone-client.py.

Basic Configuration

So, from all this, the most simple example I can come up with is the following.  To configure Apport to behave with an application, the following steps are required.

1. Configure the CrashDb

Place a CrashDb config file in /etc/apport/crashdb.conf.d called <package-name>-crashdb.conf (note: you can actually called it whatever you want… but for sanity’s sake I’d keep it as package-name ).  Inside this file place something similar to the following:

<package-name> = {
 'impl' : 'launchpad',
 'project' : '<package-name>',
 'bug_pattern_base' : None,
}

2. Install an apport hook to specify the CrashDb

Place a file in /usr/share/apport/package-hooks called <package-name>.py or source_<package-name>.py.  This file should contain the following, which simply  sets the CrashDb to use the correct configuration:

import apport

def add_info(report):
 """add report info"""

 if not apport.packaging.is_distro_package(report['Package'].split()[0]):
 report['ThirdParty'] = 'True'
 # replace <package-name> with the crashdb config defined in the previous step
 report['CrashDB'] = '<package-name>'

Testing the settings…

Assuming all has been correctly set up, you should now be able to report bugs against the custom package by entering the following command in a terminal (or using alt+f2):

ubuntu-bug <package-name>

This will open up a window allowing you to send a report.  If you click submit, you should be taken to launchpad, with a new bug being logged against the specified application.

I must warn, the sound quality is VERY dependant on your network speeds and CPU loads at either end.  If you are running a lot of programs on either the server or the client, the sound will be erratic.  See the bugs on the pulseaudio website.  I was unable to get the sound to run very smoothly for any length of time on between two Ubuntu VM’s on pulseaudio version 0.9.19-0ubuntu4.  The specific bugs are:

• http://www.pulseaudio.org/ticket/670
• http://www.pulseaudio.org/ticket/477

Either way, it is a fun exercise in pulseaudio configuration.  In order to demonstrate this I have set up two Ubuntu VM’s using VirtualBox on a local network.

Graphical Setup

The first step is to install the tools we’re going to use to configure this. Install PulseAudio Device Chooserm PulseAudio Volume Control and PulseAudio Preferences. Select these items from the Ubuntu Software Centre. You can easily reduce the list to these items by searching for pulseaudio in the search bar as shown in the following screenshot:

Screenshot of Ubuntu Software Center installing Pulseaudio

Once this is installed, you can launch it by selecting it from Applications menu.

Open the Pulseaudio Device Chooser

This will put an audio plug icon up near the clock. Left-click (or primary click) . Select “Configure local Sound Server” and change to the Multicast/RTP tab in the Preferences window:

PulseAudio Preferences

Server Computer

The first computer set-up will be the server. This is the computer you will be controlling & playing the sound from. On this computer you will need to open up rhythmbox or your chosen audio program that supports pulseaudio output. Totem or VLC also fit this prescription.

On the server computer you will want to “Enable Mutlicast/RTP sender”. If you want to play the sound out this server computer’s speakers, select “Send audio from local speakers”. If you want to be more specific about what is sent, I would recommend you select “Create separate audio device for Multicast/RTP”. For my setup, I want to be able to send only music to the stream when I want it, so I am going to chose the second option.

Client Computer(s)

The client computers will all need to be set up with the “Enable Multicast/RTP receiver” option enabled. Assuming the networks are working properly, you should immediately start hearing music on all the client computers!

Manual Configuration

If you don’t have the benefits of a running Xserver, or want to configure these settings to work on a headless machine, you will need to be manually configuring the pulseaudio config files. The pulseaudio config files are stored in /etc/pulse/system.pa if you’re running in daemon mode, and /etc/pulse/default.pa if you’re running in a per user setup (this is the default method in Ubuntu). I’m going to write this assuming you are using daemon-mode, so we will be editing /etc/pulse/system.pa.

Server Computer

To setup the server computer, you need to edit the configuration. In a terminal or on a console with admin access type the following:

sudo nano /etc/pulse/system.pa

In this file, find and uncomment the lines that look like:

load-module module-null-sink sink_name=rtp format=s16be channels=2 rate=44100 description="RTP Multicast Sink"
load-module module-rtp-send source=rtp.monitor

(If these don’t exist, just add them to the end of the file)

Once this is done, restart the pulseaudio server by running:

sudo /etc/init.d/pulseaudio restart

Client Computer(s)

The client computer will be done by editing /etc/pulse/system.pa (alternatively, you can copy this file to ~/pulse/default.pa). Edit this file by typing:

sudo nano /etc/pulse/system.pa

In this file, find and uncomment the lines that look like:

### Load the RTP reciever module (also configured via paprefs, see above)
#load-module module-rtp-recv

Again, if this doesn’t exist, just add them to the end of the file.

Once you’ve saved this, apply the changes the same way you did previously… by restarting pulseaudio:

sudo /etc/init.d/pulseaudio restart

Once again, assuming the network is behaving correctly, you should be hearing sound out both ends.

Troubleshooting & More Information

Troubleshooting guides are well written on the pulseaudio site. If you have any issues I would suggest reading the wonderful article at http://www.pulseaudio.org/wiki/HowToListenToTheRtpStream. The key thing is to check that you can see the broadcast packets (see the tcpdump section in the article).

Another good tip is to start the pulseaudio server in non-daemon mode. This will allow you to see and interact with the pulseaudio from the command line. To do this, stop any existing pulseaudio servers with the following command:

sudo /etc/init.d/pulseaudio stop # in system or daemon mode or

pulseaudio -k # for single user mode

To start pulseaudio server, run the following:

sudo pulseaudio --system -Cv # in system or daemon mode or

pulseaudio -Cv # for single user mode

Take note of any errors you see when starting this. Once the server is started, you can list the modules loaded by typing the following in the pulseaudio console:

list-modules

For more information on how to load modules see http://www.pulseaudio.org/wiki/Modules, and specifically http://www.pulseaudio.org/wiki/Modules#RTPSDPSAPTransport.

More information about the commands that can be run in the pulseaudio console, see http://www.pulseaudio.org/wiki/CLI

Now, apart from the general ‘hype’ around anything that’s meant to be able to ‘kill’ or be a ‘better’ alternative to Microsoft’s latest operating system, the idea that this particular version/distribution of Linux has the ability to put Vista to death is just absurd.

I had the oppertunity to use Vista for a time – partly as a feasibility study for my work, and partly out of my own self-interest to see what progressions / changes Microsoft had made to it’s OS.
My own personal criticism’s were that it required too much memory and drive space, and was quite a ‘bloated’ operating system in general. Now, of course, this is in light of the ‘average’ technology that is still kicking around for 90% of the populace. From that perspective, to call Ubuntu 8.04 “The Vista Killer”, would maybe be accurate. But even I, a linux user, find it a bit far fetched.

Windows is still the primary operating system being suppored by a large percentage of products – with Apple’s ‘Mac OS’ coming in second place. Adobe is a good example of industry software that is only supported on those two major operating systems.
Linux does have it’s open source ‘alternatives’, (and admittedly I’ve not spent much time in using or even trying any large number of these) but even I don’t believe that all of these are in a position yet to be used widely by industry. Don’t get me wrong, I have every faith that there will one day be open source software that is usable by various industries – but this isn’t the reality we live in. Not yet.

Sometimes I just wish that consumer-orientated publications could be a little more ‘balanced’ in their approach – and marketing. Considering the criticism’s I found with Vista, Windows 2000 could be percieved a “Vista-Killer”. So could the latest Mac OS. So could Dos.

It all comes down to what part of Vista (in this case) that you’re not liking, and want a ‘better’ alternative to.
I suppose, ultimately, it’s all subjective.