When a firm is contemplating virtualization, there are many positives: server consolidation, improved DR, reduced energy consumption, reduced infrastructure costs, etc…. There are also negatives: increased risk due to single point of failure, additional complexity, server sprawl…
Server sprawl has long been a part of the Windows Server realm, due to the overwhelming mindset of one application – One Server. One of the few things that kept server sprawl in check was the cost to procure another server. The firm would need to purchase a new server, this normally entails
- Research (find systems that meet the application requirements)
- Verify datacenter can absorb additional server (are there enough network ports, are power and cooling sufficient, is there space in the rack?)
- Requesting quotes (must work with multiple vendors to ensure best value proposition)
- Select quote (best value proposition, not always lowest cost)
- Submitting the PO to purchasing (wait out the steeping period)
- Purchasing department orders the server
- Waiting for vendor to ship (anywhere from a week to a month)
- Request storage and networking ports from the groups responsible.
- Waiting for equipment to arrive in datacenter (we work in a union facility where we are not allowed to move equipment, this usually takes a week)
- Submit change request to rack mount the server and bring it on the network (this usually must happen after hours when the server is being installed in racks that have production servers)
Now, the administrator can begin configuring the server.
- Install OS
- Install Service Packs
- Install VirusScan
- Install backup software
- Install monitoring software
- Configure monitoring
- Install support features for the application
- Patch support features
- Install application
Now, what does this have to do with server sprawl? After virtualization, skip most of the steps required to purchase a server. Instead of the approximately two months to purchase new hardware, as soon as the request is made, the VM can built almost immediately and at almost zero cost to the firm. Of course there are costs, OS licensing, backup, virusscan, monitoring, storage. But the portion of the costs that are immediately seen by the purchasing department are only for the application.
When your firm decides to move forward on your virtualization project, do not underestimate the concept of server sprawl. My previous two firms after the virtualization infrastructure was in place, experienced significant server sprawl. Projects that were originally slated for two servers became 10. Applications that were on the bubble, immediately became a go. Applications that would have previously been denied due to limited use by only a few in the company, became feasible.