Snapshots

Another valuable VMware vSphere feature is virtual machine snapshots. Snapshots give us the ability to capture point in time restore points on a virtual machine which can be utilized to test things such as upgrades, patch installations, and general configuration changes. If something were to go terribly wrong during our tests, snapshots give us the ability to failback or go to these points in time, the known good states.

Snapshots are often used in backup scenarios as well, where a snapshot will be taken to free up the underlying disk in order for it to be backed up or replicated. However, along with all of these benefits comes the drawback of the risk of a snapshot filling up a datastore if not closely monitored. To understand this, we will first look at what happens when a snapshot is taken.

Understanding vSphere Snapshots

A snapshot of a VM creates several new files on our datastore explained as follows:

• .vmsd: It contains information about the snapshot

• .vmsm: It contains a point...