When planning for a shadow copy implementation it is a good idea to plan ahead for the storage requirements of this feature. By default, this service will automatically create a 100 MB backup file when you enable it. Also, the default maximum size used for these backups will be set to 10% of the volumes total disk space. As soon as this maximum is met, VSS will begin deleting older versions of the data being backed up in order to create new backups. This being the case, you will want to plan for a larger storage maximum if you need to keep shadow copy backups for an extended amount of time.
Just remember, VSS is NOT a one-stop shop for data backups, that is, it should not be the only backup you rely on. You should always develop a full backup plan that includes off-server and off-site backups.
Chris Sanders is the network administrator for one of the largest public school systems in the state of Kentucky. Chris's specialties include general network administration, windows server 2003, wireless networking, and security. You can view Chris' personal website at www.chrissanders.org.