It should be simple to do this and it is. The hardest part was finding the correct way to do it, so for future reference:

Using the command line, you can use dpkg-reconfigure tzdata.

Follow the instructions to reconfigure the timezone. This was taken from the ubuntu wiki article

Cheers, Mark

There are a number of steps needed to get custom language files working in a nice fashion for asterisk on ubuntu.

For this example I'm going to replace the standard digits of 0 to 10 with files that I've had recorded.

Create files in the correct format:

Starting with files in the format: 0.wav, 1.wav .... 10.wav which are 44.1kHz 16 bit PCM mono wav files.

We can convert them to alaw, ulaw and gsm formats which reduces asterisk transcoding with the following script: (requires sox to be installed)

Move the files to the correct place on the server:

I'm going to use the name 'learnosity' for the language as these are the files that we've recorded. So we need to create the following directory on the asterisk machine:

If you wanted to do more audio files, you can create learnosity directories for the other audio files.

Once this is done, copy the alaw, ulaw and gsm files in but leave the original wav files out.

Tell asterisk to use these files:

The easiest way to use these language files is to set the channel language for the sections you want to use it:

Here's an example from extensions.conf:

If you dial extension 4 you get the digits 1 to 9 in the default language and if you've done everything correctly you will get your newly recorded digits the second time.

Cheers, Mark

I was recently setting up a Ubuntu server and was partitioning it after it had been installed.

There was lots of free space on the drives as the root partition was only using a small portion of the disk. After running fdisk to partition it and mkfs.ext3 on the partitions to format them I couldn't see them in /dev/disk/by-uuid.

A quick google presented the solution:

According to the man page this makes udev request the kernel device uevents, which in essence makes it read the disk info again and show it all up so you can mount it happily.

Cheers, Mark

I've been working on getting CF Sandbox security working. It's trickier than I first thought so here's how to do it for future reference:

Enable security Manager

Instructions from Steven Erat's blog:

NOTE the example from the adobe site has the quotes in the wrong place. Note you also need to change [cf_webapp_root] to match the location on your machine.

Datasources

After I enabled Datasource security I began to receive the following error, a bit of digging reminded me that the MySQL connector tries to do some autoconfiguration for coldfusion to optimise it.

It was failing to load the configuration file which is inside the mysql connector jar file /com/mysql/jdbc/configs/coldFusion.properties

I haven't gotten to the bottom of why it couldn't be loaded but adding the following to the datasource query string fixed it up:

I would suggest adding some of the settings from this file as paramaters in your datasource settings as per previous post

Note: This was using the following:

• ColdFusion 7.0.2 Cumulative Hotfix 1 Multiserver install
• MySQL connector/J 5.0.8

Hope it helps. Cheers, Mark

A current project that we are working on requires us to be able to record sound via a flash plugin. Initially I thought it would be nice and easy as I've seen demos of both video and audio broadcasting - however, the one big problem is that the current flash client only allows you to record video to a netstream, you can't get any access to it in the flash player.

So you need something like Flash Media Server or Red5 to record it.

However, once you record it to the server it is an flv and the audio codec is stored as a NellyMoser encoded audio portion. This codec is not supported by many applications and after a quick google found the nelly2pcm project on google code.

This will convert a flv sound file to a raw pcm file - which you can then do useful stuff with. So here's how to do it on a Ubuntu machine.

• Ensure you have build tools: (apt-get install build-essential)
• Download nelly2pcm from google code
• Extract and Compile it,

You should now have a nelly2pcm executable file in this directory.

You can run it as follows:

This will create a raw sound file with no headers and output the line above which you'll need for the next part.

To play this file back you can use sox (apt-get install sox)

If you've got all the options correct then this will play the file back. Once you got it correct you can then use sox to create a wav file which is essentially the same except that it has a header which contains all the settings (eg bitrate etc)

From a wav you can convert to whatever you like. I'm looking forward to the Flash Player 10 release as this messing will no longer be necessary as it will support encoding with the free Speex codec.

Cheers, Mark

Update:

In the 12 hours since I wrote this post it appears that a DMCA takedown notice has been served on the nelly2pcm site and google have taken it down. I've no idea if it's related to this post or not and no details are available yet on the chillingeffects site but hopefully it will be updated shortly. As I mentioned earlier, I can't wait for flash 10 with the speex codec so we don't have to use Nellymoser, well done Adobe for including it.

I was cleaning up some source code yesterday and wanted to print it all out, however the Mac line endings (we use Mac's and Ubuntu mostly) were messing up the printout on my Ubuntu machine.

A quick google later and I found the solution, a program called 'tr', posting here for next time:

Obviously you could convert from Unix to Mac by reversing it.

Cheers, Mark

I've been looking for a while for a way to convert DVD's and other movies that I have into iPod format and have been failing miserably. That is until today, when I came across the unusually named HandBrake.

It does exactly what is says on the tin and makes it very easy to copy dvd's. Initially I used it from my Mac and it worked flawlessly.

I also tried the Linux version on Ubuntu Hardy (8.04) which has no GUI but it is pretty simple when you get the hang of it.

Here's a typical command line:

This reads from /dev/cdrom and uses the handy "iPod Low-Rez" preset which fixes it all up nicely for the iPod.

And here's one that takes the second title:

The wiki has more information on command line usage.

Happy iPodding.

Cheers, Mark

I came across Mozilla Prism the other day and while I'm still deciding if it's going to be a permanent addition to my machine so far so good.

Prism is a cut down version of Mozilla which is designed to run single sites from icon - what's the use of that you may ask? Well it allows you to have an icon on your desktop for Gmail or Google Calendar or docs or analytics and get to it nice and quickly.

It also free's up some much needed screen real-estate as all the other toolbars relevant for a web-developers browser can get in the way and are not used when you are using you email and calendar.

Additionally - as web developer I tend to restart firefox more often than some - and having my email seperated from that is nice.

Give it a try and see if you like it. On Ubuntu Hardy you can do the following to install it:

On other platforms (windows,mac or other linux versions) you can go to the Prism site and download it.

For the different applications check out the Bundles section or the User contributed bundles section.

Obviously this shares a lot of similarities with the adobe AIR platform albeit not as full featured. It will be interesting to see what further development plans there are for the prism platform.

Cheers, Mark

One of the things that Ubuntu (gutsy 7.10) and probably most versions of linux) are currently lacking is out of the box support for power saving and hence suffers from poor battery life when unplugged.

My HP nc8430 also runs particularly hot by default - but I've spent a bit of time hunting down tips for reducing the power usage and heat produced from the laptop to get a longer battery life. I'm sure there are a lot more ways that power can be saved and I suspect that future versions of Ubuntu will catch up and produce the same level of battery life or even longer than windows.

Here is what I am using so far:

Set powerplay mode on ATI fglrx driver

If anyone has equivalent code for other video cards please let me know and I'll add it here.

Disable 'hal' from polling your cdrom

From powertop: 'hal' is the component that auto-opens a window if you plug in a CD but disables SATA power saving from kicking in.

Disable bluetooth if you are not using it

Remove the usb 1.1 kernel driver if not using it

Apparently the usb 1.1 driver does frequent polling and prevents the processor from staying in low power states for any length of time.

Increase the VM dirty writeback time

From powertop: This wakes the disk up less frequenty for background VM activity.

Turn off second processor

This is a very extreme measure and I haven't measured how much extra battery life it gives - but it is a bit cool to be able to turn it on and off if you have a dual core or dual CPU machine.

and to turn it back on use the following:

How cool is that?

Let me know if you come across any more tips. Cheers, Mark

Updated 17/Mar/07: Fixed commands based on feedback from Neil. Thanks Neil.

We uses SSH portforward's to ensure security of many of our systems as it allows us to have VPN-like functionality with a very simple configuration. As our use of it has grown over time I've become more and more familiar with the following error from SSH:

This occurs when you are already using a particular port for another port forward. Eg in this case I might be trying to forward port 2000 to two different machines. However, I came across this great and simple way to prevent this.

The basic theory is to use a unique local ip address for each portforward host you wish to connect to instead of using localhost (127.0.0.1) for each.

Set up your Hosts file

Open up your hosts file: /etc/hosts and add entries like this:

I've chosen the .fwd extension to remind me what they are for.

Set up your ssh config

Then in your .ssh/config file add the optional hostnames to the localforward:

When you connect to these systems the port forwards will now be set up.

You can access the port forwards by using system1.fwd or system2.fwd instead of localhost.

Eg: http://system1.fwd/ or http://system2.fwd/

Nice, thanks for the tip Cameron.