IT professionals may initially be awestruck by the promises of virtualization, but Gartner analysts warn that awe could turn into upset when organizations start to suffer from seven nasty side effects. Here are the reasons Gartner says virtualization is no IT cure-all:

1. Magnified failures. In the physical world, a server hardware failure typically would mean one server failed and backup servers would step in to prevent downtime. In the virtual world, depending on the number of virtual machines residing on a physical box, a hardware failure could impact multiple virtual servers and the applications they host.

2. Degraded performance. Companies looking to ensure top performance of critical applications often dedicate server, network and storage resources for those applications, segmenting them from other traffic to ensure they get the resources they need. With virtualization, sharing resources that can be automatically allocated on demand is the goal in a dynamic environment. At any given time, performance of an application could degrade, perhaps not to a failure, but slower than desired.