Properties
You can define properties when you are creating or editing objects such as channel templates, channels, packages (or repositories), instances, servers, and environments. These properties become environment variables when a command is run. You can also create or edit global server properties that are available on all these objects by default.
When the system prepares to perform an action on a managed computer, it creates environment variables for all the properties that are relevant to that context. For example, when the system deploys a package instance to a channel, the system makes available the relevant instance, channel template, channel properties as environment variables on the computer.
It is because the properties are created as environment variables, they are available to shell scripts on the remote computer: A UNIX script can access a property as $propertyName, and a Windows batch script can access a property as %propertyName%.
This topic contains the following information:
Property precedence
You can define a property with the same name on different objects. The system assigns values to the properties using the following order of precedence, from highest to lowest:
- Package reference instance (highest level)
- Instance
- Package reference
- Package / Repository
- Channel
- Channel template
- Environment
- Server
- Global server (lowest level)
For example, suppose you define a value for a property named db_user on a channel. While deploying an instance of a particular package to this channel, you changed the value for the same property. This new value that you assigned at the time of deploying the package instance, overrides the channel property.
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