Controlling dependencies with depends_on and ignore_changes

In 99% of cases, Terraform will resolve dependencies automatically. There are two problems you can encounter when you rely solely on automatic resolution:

  • Dependency is not automatically handled by Terraform
  • Dependency leads to unwanted behavior and should be omitted

For both problems, there is a solution in Terraform. Let's first look at how you can force dependencies with depends_on. For each resource, you can specify the depends_on parameter, which accepts a list of resources that this resource depends on. As a result, this resource won't be created until the ones listed inside this parameter are created.

There might be different use cases for this. For example, your private OpenStack ...

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