Variable Groups in Azure DevOps are a powerful feature for managing variables that are used across multiple pipelines. They allow you to store values that are used in more than one place, making your pipelines more maintainable and your variable management more efficient. Here’s a detailed overview of Variable Groups:

What are Variable Groups?

• Definition: Variable Groups are collections of related variables that are stored and managed together in the Azure DevOps Library. They can be used across multiple build and release pipelines.
• Common Uses: Store environment-specific settings (like URLs, connection strings, file paths), secrets (like tokens and passwords), and any other data that need to be reused across multiple pipelines.

Creating and Using Variable Groups

1. Creating a Variable Group:

   • Navigate to the Azure DevOps project.
   • Go to “Pipelines” > “Library”.
   • Click on “+ Variable Group” to create a new group.
   • Enter the name and (optionally) a description for the group.
   • Add variables to the group by specifying the name and value for each.

2. Securing Sensitive Data:

   • For sensitive data like passwords or tokens, mark the variable as a secret. This hides the value in the UI and logs.

3. Linking Variable Groups to Pipelines:

   • In your YAML pipeline, use the variables block to link to a variable group by its name.
   • In classic pipelines, you can link variable groups in the variables tab of the pipeline settings.

4. Accessing Variables in Pipelines:

   • Variables from the group can be accessed the same way as you would access other variables in your pipeline ($(variableName)).

Best Practices

• Organize by Environment: Create separate variable groups for different environments like development, testing, production, etc., to manage environment-specific configurations.
• Use Descriptive Names: Name your variable groups and variables descriptively to clarify their purpose.
• Security: Always mark sensitive data as secret. Be cautious about who has access to these variable groups.
• Audit and Rotate Secrets: Regularly audit your variable groups, especially those containing secrets, and rotate the secrets as per your security policies.
• Version Control for Variables: Consider using Azure Key Vault for managing secrets and integrating it with Azure DevOps for enhanced security and versioning of secrets.

Advantages of Using Variable Groups

• Centralized Management: Manage variables in one place rather than duplicating them across multiple pipelines.
• Maintainability: Easier to update values as they are stored in a single location.
• Security: Better management of sensitive data through secrets.
• Consistency: Ensures that all pipelines are using the same set of values, reducing errors.

In summary, Variable Groups in Azure DevOps provide a centralized, secure, and efficient way to manage variables across multiple pipelines, contributing to cleaner code and more streamlined CI/CD processes.