Getting past square one

Moreover, business procedures to prevent virtual machine sprawl, or to inform business managers about virtual IT resources operated on their behalf, may not be implemented properly. This is when other stakeholders start voicing their reservations.

The idea of virtualisation

"Everybody likes the idea of virtualisation, because consolidation saves you money and you have one server instead of a 100 or buy one PABX instead of five. So they start with a test and development environment, or a non-core application and everything looks good," says Hatfield.

"When they want to implement virtualisation beyond the 20% threshold, they start asking themselves, 'Do I have the ability to execute on my ITIL disciplines? Do I have the systems, people and processes to manage availability, to troubleshoot accurately, to provide my business stakeholders with SLAs?'.

Each layer could contain research from several vendors. However available management tools only manage one or two layers properly and as a rule work best for the vendor's own innovation. Vendor-agnostic management tools tend to lag behind and have less functionality and integration. Even experienced cloud computing players have to cobble at the same time a bunch of tools to manage performance across the entire virtualised IT stack.

Furthermore, the company may find that managing SLAs in the real computing world is bad enough, however can become unbearably uncertain in the virtualised world, which is moreover difficult to manage. Delivering SLAs means choosing management tools to enable that. The choice of management tools can at that time influence the choice of technologies.

"A business can think virtualisation is great because the amount of equipment in the data centre has been reduced dramatically," explains Green. "However if you don't have management in your IT department's DNA, at the time lurking inside those few little servers in the corner could be a worse mess than you had earlier.

The business level

“At the business level, you may need to apply a security or quality-of-service policy. In the past, the policy was applied to a physical network. Now you have a virtual machine and a virtual network card connecting to a virtual switch, which makes it more difficult to troubleshoot."

A company could as well find that a lot of its IT architecture must be overhauled earlier further steps towards cloud computing would be prudent. Its IT infrastructure might be incapable of bearing the extra loads required.

The data centre

"If we look at networking infrastructure within the data centre, there have been a number of drivers that have forced a rethink of the way we've been doing things," adds Green.

"Storage requirements have been growing over the years. A secure and high-speed network to transport information from storage devices to servers is essential to take advantage of the workload mobility, redundancy and high availability features that virtualisation provides."