github.com/jmbataller/terraform@v0.6.8-0.20151125192640-b7a12e3a580c/website/source/docs/configuration/environment-variables.html.md (about)

     1  ---
     2  layout: "docs"
     3  page_title: "Environment Variables"
     4  sidebar_current: "docs-config-environment-variables"
     5  description: |-
     6    Terraform uses different environment variables that can be used to configure various aspects of how Terraform behaves. this section documents those variables, their potential values, and how to use them.
     7  ---
     8  
     9  # Environment Variables
    10  
    11  ## TF_LOG
    12  
    13  If set to any value, enables detailed logs to appear on stderr which is useful for debugging. For example:
    14  
    15  ```
    16  export TF_LOG=TRACE
    17  ```
    18  
    19  To disable, either unset it or set it to empty. When unset, logging will default to stderr. For example:
    20  
    21  ```
    22  export TF_LOG=
    23  ```
    24  
    25  For more on debugging Terraform, check out the section on [Debugging](/docs/internals/debugging.html).
    26  
    27  ## TF_LOG_PATH
    28  
    29  This specifies where the log should persist its output to. Note that even when `TF_LOG_PATH` is set, `TF_LOG` must be set in order for any logging to be enabled. For example, to always write the log to the directory you're currently running terraform from:
    30  
    31  ```
    32  export TF_LOG_PATH=./terraform.log
    33  ```
    34  
    35  For more on debugging Terraform, check out the section on [Debugging](/docs/internals/debugging.html).
    36  
    37  ## TF_INPUT
    38  
    39  If set to "false" or "0", causes terraform commands to behave as if the `-input=false` flag was specified. This is used when you want to disable prompts for variables that haven't had their values specified. For example:
    40  
    41  ```
    42  export TF_INPUT=0
    43  ```
    44  
    45  ## TF_MODULE_DEPTH
    46  
    47  When given a value, causes terraform commands to behave as if the `-module=depth=VALUE` flag was specified. Modules are treated like a black box and terraform commands do not show what resources within the module will be created. By setting this to -1, for example, you enable commands such as [plan](/docs/commands/plan.html) and [graph](/docs/commands/graph.html) to display more detailed information.
    48  
    49  ```
    50  export TF_MODULE_DEPTH=-1
    51  ```
    52  
    53  For more information regarding modules, check out the section on [Using Modules](/docs/modules/usage.html).
    54  
    55  ## TF_VAR_name
    56  
    57  Environment variables can be used to set variables. The environment variables must be in the format `TF_VAR_name` and this will be checked last for a value. For example:
    58  
    59  ```
    60  export TF_VAR_region=us-west-1
    61  export TF_VAR_ami=ami-049d8641
    62  ```
    63  
    64  For more on how to use `TF_VAR_name` in context, check out the section on [Variable Configuration](/docs/configuration/variables.html).