Virtualization is definitely saving the IT cost and most of the companies are benefiting from it.But at the same time, you should not virtualize the all the environment using hypervisors without analyzing it. Hypervisor Virtualization may not be a good choice for heavy work load systems and some specific applications. These items needs to be identified prior to the environment design process. What are things that you need to be consider prior to virtualizing your environment ?
- Application support – Architecture
- High Resource consuming applications
- Application Vendor support
- Application Licensing
Application Supported Architecture:
Most of the hypervisor are X86 (CISC) architecture based. But there are some application has been developed to run only on RISC architectures like Sun SPARC, IBM Power or HP-UX PA-RISC. In this scenario, you should not think of virtualization using hypervisors. But still you can use those specific architecture’s virtualization. (Ex: Oracle Solaris’s zone , HP-UX’s vpar & IBM AIX’s LPAR).In some rare cases , application requires specialized hardware.For an example, application may require Fax boards, serial ports,and security dongles and its very difficult to run application on virtual environment since high risk associated with it. Its better to continue with physical server.
High Resource consuming applications
High CPU/Memory consuming applications are not the right candidate to virtualize it since we are not going to get much benefits from it. If you configure the high resource consuming virtual machine on hypervisor environment, it will create negative impact on the other workloads.Plenty of resources required to failover from one node to another if the VM is quite large. It’s better to leave such a applications on the physical servers.
Application Vendor support
You will definitely required vendor support to fix the issues and getting the regular update from application vendors. If they are not supporting the application on the virtual environment, then you have no choice to leave it as it is. But this is very rare case where vendors do not support their apps on virtual environment.
Licensing issue raises when you are migrating from the physical server to virtual environment. OEM (original equipment licenses ) are not transferable from physical to virtual . You need to acquire new licensing and but again cost involved.Some of the license may be tied with MAC or drivers . In this case , you need to work with application vendors and to get it fix.
Except the above cases , you must virtualize your environment using the hypevisors(VMware ESXi , Oracle VM or RHEV) to save the IT cost and servers consolidation(Reduce the datacenter space).