About virtual business services
For a business service to work properly, it is important that all of its tiers and components are up and working together. From a business continuity point of view, it is important to not just ensure that individual tiers are up and running but also the entire business service.
A virtual business service (VBS) is a logical collection of resiliency groups that function together to perform a particular business service. A VBS enables easy management of multi-tier business services. For example, you can group a web server resiliency group, a database resiliency group, and a payroll business logic resiliency group into a VBS called payroll. You can start, stop, monitor, manage, or recover that VBS as a single entity.
Note:
If a VBS consists of resiliency groups that are in maintenance mode, then you cannot perform any operations on the VBS.
Within a VBS, resiliency groups are arranged in tiers. Tiers represent the logical dependencies between the resiliency groups and determine the relative order in which the resiliency groups start and stop. For example, the database resiliency group must start before the application server resiliency group and the web server resiliency group, so the database resiliency group must go in the lowest tier. The application server resiliency group must start after the database resiliency group, so it goes in the next tier. The web server resiliency group must start last, so it goes into the top tier. Later, if you add a resiliency group to the VBS, you can manage it as part of the IT service by placing it in the appropriate tier.
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