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Virtualization in today's world is attracting quite a lot of attention. In the era of power-packed machines, one would not prefer to dedicate an entire piece of costly hardware to a single cause. From running multiple applications to multiple operating systems (OS) to multiple hardware domains, it's all about making the most out of a box. But to truly leverage the positives of virtualization, the applications need to be supportive enough. Most modern-day software run on virtual platforms as if virtualization was transparent, which is really what the intent is.

For the sake of this experiment, VMware was chosen as the virtualization technology, mostly due to the fact that it has been around for quite some time now. Support for the Solaris(TM) 10 OS (both 32- and 64-bit versions) as a guest operating system, is already present in multiple flavors of VMware. VMware ESX Server 3.0.1 (http://www.vmware.com/products/vi/esx/) with the features it provides, was the platform of choice. Documentation for VMware ESX server can be found at http://www.vmware.com/support/pubs/vi_pubs.html. I would like to add that I did try my hands on VMware Workstation and VMware Server, but certain areas like networking and shared devices in a clustered setup with Sun Cluster 3.2 software, had problems in areas like Private Interconnects and Device Fencing.

The aim was to run Sun Cluster 3.2 software on top of Solaris 10 guest OSes, and thereby cluster VMware Virtual Machines running the Solaris OS. The initial assumption was that, since Solaris OS runs on VMware without problems, Sun Cluster software should work just fine! It makes sense to mention up front here that these are initial steps in this direction, and the Sun Cluster team is continuously investigating various virtualization techniques and Sun Cluster support for them. The setup mentioned here was done on 32-bit Solaris (purely due to available hardware at the time of this setup), but I must say that I strongly believe that things won't look or work any different in a 64-bit environment.

Given below are the various aspects of the setup. All mention of nodes and guests here refers to the virtual Solaris guests on VMware ESX Server, which are to be clustered using Sun Cluster 3.2 software.

Read the original, here, to find out all the steps involved.