Terraform Kubernetes Manifest Error: Access Denied to “/apis”

Encountering a common issue where users face ‘forbidden access’ errors when deploying resources with Terraform into a Kubernetes cluster managed by Google Cloud Platform (GCP). The error message suggests that the “system:anonymous” user cannot reach or interact with GCP APIs. Here’s how to address it and ensure smooth deployment of your infrastructure as code using Terraform.

Understanding the Error Message

When deploying resources like grafana-agent through a Kubernetes manifest in Terraform, you might encounter:

forbidden: User "system:anonymous" cannot get path "/apis"

This error occurs because of insufficient permissions when trying to interact with the GCP APIs at planning time. Essentially your terraform configuration lacks authentication or proper access controls needed for operations on gcp_container resources within Terraform’s resource block:

resource "kubernetes_manifest" "my-node-exporter" {
  manifest = jsonencode({...}) # Your node exporter setup here.
}

The Root Cause and Solution for ‘System Anonymous User Issue

The root of this issue often lies in the way state files are managed, especially when using a version control system like GitLab:

• State Files Outside Version Control: Terraform’s remote backend requires that your .tfstate file (which stores infrastructure information) is not under source code management. Excluding it prevents merge conflicts and unexpected changes during concurrent operations on the state, which could lead to such permission errors.

• State Management Best Practices in GitLab: For effective collaboration without these issues:

  • Maintain your .tfstate file outside of version control (either locally or via a remote backend that does not use source code repositories). This ensures the state remains consistent despite multiple team members making changes.

• Remember to Fetch State Before Applying: Ensure all contributors fetch and pull latest Terraform plan before applying their local terraform apply. Without this, attempting simultaneous deployments can cause conflicts like unauthorized access errors due to state file inconsistencies.

Resolution Steps for ‘Forbidden Access’ Errors in GCP with Kubernetes Manifest Resources:

1. Migrate State Files: If your .tfstate is already under version control, migrate it out immediately as a first step towards resolving these issues by either keeping the state locally or using remote backends like S3 that are not exposed via source code repositories (e.g., Terraform Cloud).

2. Version Control Conventions: Establish clear conventions for handling .tfstate files within your team’s processes, ensuring everyone understands the importance of keeping them outside version control systems like GitLab or GitHub to avoid conflicts and errors during state synchronization between collaborators’ environments.

3. State Fetching Before Applying: Make it a standard practice for all contributors within your team workflow that they must fetch an updated Terraform plan from the remote backend before executing local terraform apply. This helps ensure everyone is starting with a consistent state and reduces conflicts during simultaneous deployments or updates.

4. Review Kubernetes Manifest Requirements: Ensure you’re reading through provider documentation, as some Terraform resources like those in the ‘kubernetes_manifest’ module may require different configurations for API access compared to standard GCP modules (e.g., google_container). If they do need additional setup or separate plan/apply phases are necessary due to permission requirements during planning time—follow these guidelines accordingly, as stated:

   This resource requires API access during the planning phase and thus cannot be created in a single apply operation. Please ensure that your Kubernetes manifests have proper permissions beforehand or arrange them into separate Terraform files for resources requiring different environments (development/staging).
   

5. Following Best Practices: Leverage best practices by structuring multiple .tf configuration modules if needed, each tailored to its specific environment requirements and maintain clear separation between these configurations—like separating development-specific resource definitions from staging or production ones for a cleaner workflow across various environments within Terraform.

6. Consistent Communication: Keep lines of communication open among team members regarding changes in the state file’s location, access permissions and overall practices around version control systems to prevent such conflicts arising during collaborative work on infrastructure as code projects involving Kubernetes resources with GCP backend services through Terraform.

By adhering closely following these steps focused mainly towards effective management of remote backends for state files alongside understanding the necessary setup or separation required by specific modules, teams can effectively mitigate ’ forbidden access’ issues when using terragrunt and associated tools in conjunction with deployments to Kubernetes clusters via Terraform.