How to fix Error: Invalid filesystem path in Terraform

TerraformINTERMEDIATEHIGHUpdated Dec 30, 2025· 135 views

This error occurs when Terraform cannot access, locate, or properly resolve a filesystem path referenced in your configuration. It commonly happens with the file() function, module sources, or backend configurations when paths are incorrect, relative paths are misused, or files don't exist.

Quick fix

Fixes Error: Invalid filesystem path

resource "aws_lambda_function" "example" {
  filename = "lambda.zip"  # Will fail - relative to CWD, not consistent
  handler  = "index.handler"
}
  1. Use path.module or path.root for relative file references
  2. Verify the file exists before running terraform
  3. Update module source paths to use relative paths from root module
  4. Check for symlinks and resolve them
terraform — error
resource "aws_lambda_function" "example" {
  filename = "lambda.zip"  # Will fail - relative to CWD, not consistent
  handler  = "index.handler"
}
Error: Invalid filesystem path

What this error means

In Terraform, the "Invalid filesystem path" error indicates that Terraform tried to reference a file or directory that it cannot find, read, or access. This typically happens when using the `file()` function to read local files, specifying module sources as local paths, or configuring backends that reference local state directories. The error can occur during `terraform init`, `terraform plan`, or `terraform apply` phases. Terraform expects all files referenced in configuration to exist at evaluation time, not to be created by resources during the run.

Typical symptoms

  • terraform init, plan, or apply fails with 'Invalid filesystem path' or 'Invalid value for path parameter' message
  • Error occurs when using file() function to read local files like JSON schemas, SSH keys, or scripts
  • Module source paths cause errors when calling local modules with relative paths
  • Backend configuration fails because Terraform cannot find the state file path
  • Commands fail differently depending on which directory you run terraform from

Common causes

  1. Relative paths like './' or '../' are used without proper path interpolation, breaking when terraform runs from different directories
  2. The file() function references a file that doesn't exist or has a typo in the path
  3. Absolute paths are hardcoded instead of using path.module or path.root variables, causing portability issues
  4. Symlinks point to locations outside the configuration directory, breaking in Terraform Cloud/Enterprise
  5. Module sources use relative paths that resolve differently from the root module context
  6. Working directory changed between terraform runs without properly resolving path references

How to fix "Error: Invalid filesystem path"

1Use path.module or path.root for relative file references

The most common fix is to replace relative paths with path.module (current module directory) or path.root (root module directory).

Instead of this (WRONG):

hcl
resource "aws_lambda_function" "example" {
  filename = "lambda.zip"  # Will fail - relative to CWD, not consistent
  handler  = "index.handler"
}

Do this (CORRECT):

hcl
resource "aws_lambda_function" "example" {
  filename = "${path.module}/lambda.zip"
  handler  = "index.handler"
}

This ensures the file is located relative to the module file itself, not wherever terraform is run from.

2Verify the file exists before running terraform

Check that the file you're referencing actually exists at the specified path:

bash
# From your terraform working directory:
ls -la ./lambda.zip
ls -la ./templates/policy.json

# Or use absolute path:
ls -la /home/user/project/lambda.zip

The file() function only works with files that are part of your configuration source code. It cannot reference files that will be created by resources.

3Update module source paths to use relative paths from root module

When calling local modules, use paths relative to the root module:

Instead of this (may fail):

hcl
module "vpc" {
  source = "./modules/vpc"  # OK from root, but fragile from subdirectories
}

Better approach (always works):

hcl
module "vpc" {
  source = "${path.root}/modules/vpc"
}

This is especially important in Terraform Cloud/Enterprise or when modules are called from different contexts.

4Check for symlinks and resolve them

If you have symlinks in your configuration directory, especially ones pointing outside the repository:

bash
# Find all symlinks:
find . -type l -ls

# Resolve symlinks to actual paths:
ls -L ./config-file

Symlinks that point outside your configuration directory will break in Terraform Cloud/Enterprise because the worker doesn't have access to those external paths. Consider copying the file instead or using an absolute path that exists on the remote runner.

5Use pathexpand() for home directory references

If you need to reference files in a user's home directory (like SSH keys), use the pathexpand() function:

hcl
# Instead of:
provisioner "remote-exec" {
  private_key = file("~/.ssh/id_rsa")  # May fail - ~ not expanded
}

# Do this:
provisioner "remote-exec" {
  private_key = file(pathexpand("~/.ssh/id_rsa"))
}

This ensures tilde (~) expansion works correctly on all platforms.

6Diagnose WSL path issues on Windows

If running Terraform on Windows Subsystem for Linux (WSL), be aware of cross-filesystem path issues:

bash
# Verify file is accessible from Terraform's perspective:
cat /path/to/file

# Check if path is on WSL filesystem (preferred) vs Windows drive:
pwd  # Should show /home or /mnt paths

# If file is on Windows drive (/mnt/c/Users/...), consider:
# 1. Copy file to WSL home directory
# 2. Use absolute path with proper escaping

WSL can have issues with path transformations between Windows and Linux filesystems. Keeping your terraform files and referenced files on the WSL side (/home/user) avoids most issues.

Advanced notes

Path Functions Reference:
- path.module: Directory of the current module file
- path.root: Directory of the root module (where you run terraform init)
- path.cwd: Current working directory (less reliable, avoid in modules)
- abspath(): Returns absolute path of a file
- pathexpand(): Expands ~ in paths for home directory access

Terraform Cloud/Enterprise Considerations:
Files in your configuration must be accessible to the remote runner. Symlinks pointing outside the configuration directory or to the local filesystem won't work. Instead:
1. Include files directly in the configuration directory
2. Use variables or data sources to get file contents from external systems
3. Reference files by absolute paths only if they exist on the runner

Module Development Best Practice:
Always use ${path.module} in modules so they work correctly regardless of where they're called from. Never assume the working directory matches the module directory.

Frequently asked questions

What does "Error: Invalid filesystem path" mean?
In Terraform, the "Invalid filesystem path" error indicates that Terraform tried to reference a file or directory that it cannot find, read, or access. This typically happens when using the file() function to read local files, specifying module sources as local paths, or configuring backends that reference local state directories. The error can occur during terraform init, terraform plan, or terraform apply phases.
How do I fix "Error: Invalid filesystem path"?
This error occurs when Terraform cannot access, locate, or properly resolve a filesystem path referenced in your configuration. It commonly happens with the file() function, module sources, or backend configurations when paths are incorrect, relative paths are misused, or files don't exist.
What causes "Error: Invalid filesystem path"?
Relative paths like './' or '../' are used without proper path interpolation, breaking when terraform runs from different directories The file() function references a file that doesn't exist or has a typo in the path Absolute paths are hardcoded instead of using path.module or path.root variables, causing portability issues
Is the "Error: Invalid filesystem path" error serious?
Yes. This is a high-severity error that usually blocks work until it is fixed, but the steps above resolve it.

Official resources & further reading