Ubuntu's mouse testing application will make you smile

Enchanting cloud with juju !

Automating infrastructure is not a new thing, but doing so with the ease of setting up paas is still in its infancy. As an interesting solution to this, Cannonical has recently come out with a PAAS tool Juju that can easily setup, configure, provision, include and change master/slaves, provide continuous integration environment among other things. This tool has not come out from wild, but is currently in use: Juju and MaaS are the default deployers for Openstack. So all large Openstack deployments that are currently happening on Ubuntu use Juju and MaaS. Additionally Ubuntu One and other Ubuntu cloud services are all running on top of Juju.
Juju might sound similar to Puppet or Chef, but rather than just providing a server, this provides various services. Internal to each juju are different charms that call various programs and provide the infrastructure to the juju. The charms App Store contains charms on various services which can be used in the juju to solve  a particular task. There are currently hundreds of different charms available - from databases to php/ruby/python servers to nosql and hadoop instances and a growing community of developers who customize and release their own customized charms.
One feature that is worth mentioning is the ability to create a traditional Paas such as CloudFoundary as a charm to run over juju.
For instance, here's the procedure to boot off a rails sever:
juju deploy rails myapp --config sample-app.yml
(This yml file contains the url to the github repository containing the charm)
juju deploy haproxy
juju add-relation haproxy myapp
Now the database can be created:
juju deploy postgresql
juju add-relation postgresql:db myapp
then migrate the database
juju ssh myapp/0 run rake db:migrate
Finally expose the proxy
juju expose haproxy
and view the status, which should provide you with the public url
juju status haproxy
The coolest feature now is to add/remove servers horizontally through gui or through command as:
juju add-unit myapp 
juju remove-unit myapp
Currently, there is also a charm-championship taking place  that encourages developers to take part in developing customized charms for various themes.
So what are you waiting for?
Jump right in at https://jujucharms.com to see it in action.

Repairing your problematic display drivers

I am sharing a recent experience with my laptop. It is a MSI CR-500 that houses an Nvidia GeForce 8200m G graphics card. In previous Ubuntu(11.04 and earlier) versions, the stock graphics driver resulted in suboptimal displays and compiz and other desktop polishing tools were not able to be installed.

Out of habit, I tried to install a custom Nvidia binary driver into my newly installed Ubuntu 12.04 last week but the graphics driver failed to install correctly. The newer linux kernal did not allow my exsiting drivers to install so had to download a newly released driver. Undaunted, I tried installing a new driver, but it failed and my graphics display manager went kaput.

To get the things back, I simply reinstalled the Ubuntu and got my settings back. Here's what I did:

Booted off 12.04 livecd/pen drive

• In install option window, went to manual drive partitioning option
• Selected the partition containing the 12.04 and set its mount point to /
• Did not select the format disk option – to retain my earlier settings and installations.

It gave me a warning specifying deletion of files.

The OS got restored in 20 minutes and I was good to go!

NOTE : Nothing much got deleted as I was having a fairly new OS with not much loaded components. Surprisingly, the java7 unzipped at /usr/local/lib was untouched, but the scala installed at /home/sumit was removed.