Configuration of 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.

The default parameters associated with this test are as follows:

• The TEST PERIOD list box helps the user to decide how often this test needs to be executed.

• In the HOST text box, the IP address of the host for which the test is to be configured has to be specified.

• The DD FREQUENCY parameter refers to the frequency with which detailed diagnosis measures are to be generated for this test. The default is 1:1. This indicates that, by default, detailed measures will be generated every time this test runs, and also every time the test detects a problem. You can modify this frequency, if you so desire. Also, if you intend to disable the detailed diagnosis capability for this test, you can do so by specifying none against DD FREQUENCY .

• To make diagnosis more efficient and accurate, the eG suite embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the DETAILED DIAGNOSIS capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option.

  The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled:

  • The eG manager license should allow the detailed diagnosis capability.

  • Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.

• If multiple components of the same component type are awaiting configuration, then an APPLY TO OTHER COMPONENTS check box will appear in this page. Clicking on this check box will allow you to apply the configuration to all/selected components of that type.

• Once the necessary values have been provided, clicking on the UPDATE button will register the changes made.

When changing the configuration for specific servers, a “*” beside the text box corresponding to the parameter signifies that these values have to be manually configured by the user. The parameter values that require to be configured will typically be prefixed with a “$” or contain a series of “*”. A value of “none” in the parameter value indicates that the corresponding parameter value can be changed if required.