7.3

Creating Explicit Dependencies and Controlling the Order of
Provisioning
If you need information from one of your blueprint components to complete the provisioning of another
component, you can draw an explicit dependency on the design canvas to stagger provisioning so the
dependent component is not provisioned prematurely. Explicit dependencies control the build order of a
deployment and always trigger dependent updates during a scale in or scale out operation.
When you design blueprints with multiple machines and applications, you might have properties you need
from one machine to finish an application installation on another. For example, if you are building a Web
server you might need the host name of the database server before you can install the application and
instantiate database tables. If you map an explicit dependency, your database server starts provisioning
when your Web server finishes provisioning.
To map a dependency on your design canvas, you draw a line from the dependent component to the
component you are depending on. When you are finished, the component you want to build second has
an arrow pointing to the component you want to build first. For example, in the Controlling the Build Order
by Mapping Dependencies figure, the dependent machine is not provisioned until the primary machine is
built. Alternatively, you can configure both machines to provision simultaneously but draw a dependency
between the software components.
Figure 3‑7. Controlling the Build Order by Mapping Dependencies
If you are designing blueprints to be scalable, it is a best practice to create single layer blueprints that do
not reuse other blueprints. Normally, update processes during scale operations are triggered by implicit
dependencies such as dependencies you create when you bind a software property to a machine
property. However, implicit dependencies in a nested blueprint do not always trigger update processes. If
you need to use nested blueprints in a scalable blueprint, you can manually draw dependencies between
components in your nested blueprint to create explicit dependencies that always trigger an update.
Managing the Service Catalog
The service catalog is where your customers request machines and other items to provision for their use.
You manage user access to the service catalog items based on how you build services, entitle users to
one or more items, and apply governance.
The workflow that you follow to add items to the service catalog varies based on whether you create and
apply approval policies.
Configuring vRealize Automation
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