Measures reported by VSSStatusTest

Volume Shadow Copy Service (VSS) server coordinates the actions that are required to create a consistent shadow copy (also known as a snapshot or a point-in-time copy) of the data that is to be backed up. A complete VSS solution requires all of the following basic parts:

• VSS service - Part of the Windows operating system that ensures the other components can communicate with each other properly and work together.
• VSS requester - The software that requests the actual creation of shadow copies (or other high-level operations like importing or deleting them). Typically, this is the backup application. The Windows Server Backup utility and the System Center Data Protection Manager application are VSS requesters. Non-Microsoft® VSS requesters include nearly all backup software that runs on Windows.
• VSS writer - The component that guarantees we have a consistent data set to back up. This is typically provided as part of a line-of-business application, such as SQL Server® or Exchange Server. VSS writers for various Windows components, such as the registry, are included with the Windows operating system. Non-Microsoft VSS writers are included with many applications for Windows that need to guarantee data consistency during back up.
• VSS provider - The component that creates and maintains the shadow copies. This can be the software or the hardware. The Windows operating system includes a VSS provider that uses copy-on-write. If you use a storage area network (SAN), it is important that you install the VSS hardware provider for the SAN, if one is provided. A hardware provider offloads the task of creating and maintaining a shadow copy from the host operating system.

Sometimes, errors may be detected when the above-mentioned parts create shadow copies of the data. Such errors can cause severe processing bottleneck and data loss while creating shadow copies. More specifically, errors in the VSS writer's operation when left unnoticed can cause serious inconsistencies in data backup. This is why, it is necessary for the administrators to capture such errors at the earliest and rectify them as soon as they are detected. In such a way, administrators can prevent data loss and enhance data consistency and integrity. The VSSStatusTest test helps administrators in this regard!

This test continuously monitors the operations of VSS server on the target host and reveals the count of writers that perform erroneous operation.

Outputs of the test : One set of results for the host that is being monitored.

The measures made by this test are as follows: