Dell EMC Avamar for Windows Servers 19.7 User Guide

How Avamar works with supported VSS writers

VSS writers provide metadata about what data to back up, and specific methods for correctly handling components and applications during backup and restore. VSS writers also identify the type of application or service in the backup, such as System Boot or System Services.

Writers are only available for active services or applications. If a service or application is present but is not active, then information from its writer is not available. Consequently, a writer can appear or disappear from backup to backup.

During a backup, Avamar checks the following conditions:

• Whether the writer for the application is present and active.
• Whether the writer appears in the list of supported writers.
• Whether a user has disabled the writer.

If the writer is present, active, supported, and enabled, then Avamar backs up the data by using VSS technology. Otherwise, the backup does not include the data that the writer serves.