1. How are versions of virtual-machine snapshots of images tracked?

The 'snapshots' of images (including virtual-machine guest-operating-system states) must be tracked in terms of where they sit on the network, how they are being used and their appropriate fix and patch status.

A popular use of virtual-machine technology is wrapping guest operating systems (with applications) into ISO or other mountable images that subsequently can be deployed in arrays of servers as virtual guests.

It can be critically important to make sure the images contain dependency modules and patches and fixes, and are otherwise in revision synchronization with each other, as well as with corporate-update policy.

2. How are moves, adds and changes administered?

Virtualization implies mobility for hosts, guest operating systems and the applications that run on them. Because virtual machines are built to house numerous guest operating systems per host, moves, adds and changes will occur to guest operating-system or application instances.

Keeping track of these developments is necessary, as is tracking host or neighboring-guest resource use and performance.

Although each virtual-machine product vendor tracks performance and keeps statistics for location and performance control, heterogeneous guest hosts coupled to volatile guest operating systems and applications can present challenges to administrators auditing guests, applications and behavior.

3. How are virtual-machine and application dependencies kept in check?

One of the benefits of a virtual machine environment is an agility that lets virtual-machine-supported applications be moved from one host hardware platform to another.