R is a statistical package to analyze data. I came across this framework while exploring Hortonworks Hadoop Data Platform and want to list down the steps to setup R – Steps on how to use R is not covered here:

1. Open Terminal and Run following commands:
~~~
sudo apt-get update
sudo apt-get install r-base
~~~
2. Above would install R 2.14.1. To upgrade to latest version, append following to “/etc/apt/sources.list” and run “sudo apt-get update” once again:
~~~
deb http://cran.rstudio.com/bin/linux/ubuntu precise/
~~~

3. In my Ubuntu, executing above, generated following error:
~~~

W: GPG error: http://cran.rstudio.com precise/ Release: The following signatures couldn’t be verified because the public key is not available: NO_PUBKEY 51716619E084DAB9
~~~

4. To resolve above error, execute following commands:
~~~
gpg –keyserver pgpkeys.mit.edu –recv-key 51716619E084DAB9
gpg -a –export 51716619E084DAB9 | sudo apt-key add –
~~~
Reference: http://ubuntuforums.org/archive/index.php/t-2154184.html

5. Run following command to upgrade all packages:
~~~
sudo apt-get upgrade
~~~

Note: To find #packages ubuntu has, use following command – more #packages, more time is taken to upgrade (be ready to do plan for alternative task during this time – upgrade took me 2-3 hours):
~~~
dpkg –get-selections | grep -v deinstall > packages.txt
~~~

Reference: ubuntuforums.org/archive/index.php/t-2154184.html

6. Run “R” in terminal and we would see R’s console.

There are many virtualization technologies are available in the market today, some of them are OpenVZ, Xen, KVM and VMware, you can understand about all these technologies.

OpenVZ:

It is an operating system level virtualization technology based on linux kernel and it allows a physical server to run multiple operating systems. It creates multiple secure and isolated linux containers on a single physical server, each container performs as a standalone server and a container can independently reboot. It is a free service and runs only linux based operating systems such as Fedora, Debian, Centos and Gentoo.

Xen:

Xen is an open source software, it allows multiple operating systems to run on a single physical computer by using a layer called a hypervisor. The Hypervisor is a program that allows multiple operating systems to share a single hardware. Xen supports Linux kernels through an approach called paravirtualization. It is used for both linux and windows.

KVM:

KVM stands for kernel based virtual machine, built for linux OS that enables linux to work as a hypervisor to run multiple virtual machines. It is designed to operate on x86-based processor architecture. It is free and supports Linux, windows, salaries and BSD guests, It is the basis for IBM’s and Red hat’s Linux virtualization technologies, it is the most used technology in the OpenStack cloud. OpenStack is a global collaboration of developers and technologists to produce an open cloud computing platform.

VMware:

It is Cloud computing and virtualization software for x86 compatible computers, it is based on ESX/ESXi bare metal hypervisor. VMware ESX and ESXi can be deployed as part of the VMware infrastructure to empower centralized management for enterprise desktops and data center applications. VMware server works with Linux, Windows, Solaris and Netware. It is the most mature virtualization and most expensive also.

Eventually Virtualization technology employed by virtual private servers, whereby a physical server divided into virtual divisions, and these technologies provides you higher reliability and greater performance.

– See more at: http://www.alphavbox.com/blog/a-guide-to-virtualization-technologies/#sthash.qOaRXKSf.dpuf