maintenance

Absolutely, Pavan! Terraform infrastructure is not “set and forget”—you need ongoing maintenance tasks to ensure it stays reliable, secure, and compatible with cloud provider updates. I’ll list the key tasks and add examples where necessary.

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Terraform Maintenance Tasks

1. Update Terraform CLI

• Terraform releases new versions with bug fixes, new features, security updates.

• Keep your Terraform CLI updated.

• Steps:

  terraform -version       # check current version
  tfenv install 1.6.0     # using tfenv for version management
  tfenv use 1.6.0
  terraform init -upgrade  # upgrade provider plugins for new version

• ⚡ Tip: Always check the upgrade guides between major versions; there can be breaking changes.

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2. Update Providers

• Providers (AWS, Azure, GCP, Kubernetes, etc.) release updates for:

  • New services/features

  • Bug fixes

  • Deprecations

• Steps to upgrade:

  1. Update provider version in your configuration:

     terraform {
       required_providers {
         aws = {
           source  = "hashicorp/aws"
           version = "~> 6.0"   # previously 5.0
         }
       }
     }

  2. Run terraform init -upgrade

  3. Run terraform plan → check changes

  4. Run terraform apply

• ⚡ Tip: Test provider upgrades in a non-production workspace first.

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3. Update Modules

• Modules (both local and remote) may have new features or fixes.

• Steps:

  1. Update version in module block (for remote modules):

     module "vpc" {
       source  = "terraform-aws-modules/vpc/aws"
       version = "4.0.1"   # upgrade to 5.x
       ...
     }

  2. Run terraform init -upgrade

  3. Run terraform plan → verify changes

• ⚡ Tip: Check module changelogs for breaking changes.

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4. State File Maintenance

• Terraform keeps all tracked resources in the state file.

• Tasks:

  1. Backup state regularly (especially for remote backend)

  2. State locking for team collaboration (S3 + DynamoDB)

  3. State cleanup: Remove orphaned or drifted resources

     terraform state list
     terraform state rm <resource>
     terraform state mv <resource> <new_address>

• ⚡ Tip: Avoid manually editing state unless necessary; use Terraform commands.

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5. Drift Detection

• Cloud resources may change outside Terraform (manual console changes or scripts).

• Tasks:

  • Run terraform plan periodically to detect drift

  • Reconcile changes via terraform apply or correct manually

• ⚡ Tip: Drift detection is essential in production environments to prevent unexpected failures.

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6. Variable & Secrets Updates

• Update .tfvars or environment variables if:

  • Resource sizes change (e.g., EC2 type)

  • New passwords, API keys, or IAM roles are required

• ⚡ Tip: Use Vault or Secrets Manager instead of hardcoding sensitive data.

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7. Resource Lifecycle & Upgrades

• Periodically check:

  • Terraform resources that require replacement on version upgrade

  • Deprecated resources or arguments

• Example: aws_instance may need create_before_destroy or updated AMI ID

• ⚡ Tip: Use lifecycle blocks to prevent accidental destruction.

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8. Remove Unused Resources

• Clean up resources that are no longer used.

• Steps:

  1. Remove resource from .tf file

  2. Run terraform plan → verify destroy

  3. Run terraform apply

• ⚡ Tip: Avoid manual deletion in the cloud; always manage through Terraform.

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9. Terraform Code Refactoring

• Keep Terraform code clean and maintainable:

  • Use modules for repeated infrastructure

  • Use variables & outputs consistently

  • Split environment-specific configs

  • Format code using terraform fmt

• ⚡ Tip: Use tflint and checkov for linting and security checks.

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10. Security Maintenance

• Ensure your infrastructure is secure and compliant:

  • Rotate credentials / API keys

  • Use IAM least privilege policies

  • Ensure S3 buckets and databases are encrypted

  • Keep Terraform state secure (sensitive data should be sensitive = true)

• ⚡ Tip: Integrate automated security scanning in your CI/CD pipeline.

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11. Terraform Plan Review

• Before applying any updates:

  1. Run terraform plan

  2. Review for unintended changes (e.g., destroy instead of modify)

• ⚡ Tip: Always use -out=tfplan and share for peer review in production.

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12. Terraform Upgrade Automation

• Automate maintenance via CI/CD pipelines:

  • Scheduled Terraform plan checks

  • Automated provider/module upgrades

  • Drift detection & alerts

• Example:

  name: Terraform Plan
  on:
    schedule:
      - cron: "0 2 * * *"
  jobs:
    terraform:
      runs-on: ubuntu-latest
      steps:
        - uses: actions/checkout@v2
        - uses: hashicorp/setup-terraform@v2
        - run: terraform init -upgrade
        - run: terraform plan

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✅ Summary of Maintenance Tasks

Task	Purpose
Terraform CLI Upgrade	New features, bug fixes, security
Provider Upgrade	Cloud provider API updates, new services
Module Upgrade	Bug fixes, feature updates
State Management	Backup, lock, cleanup, drift detection
Variable/Secrets Updates	Update sensitive or environment-specific configs
Resource Lifecycle	Ensure resources are up-to-date, prevent accidental destroy
Cleanup Unused Resources	Avoid cloud cost and clutter
Code Refactoring	Maintain readability and modularity
Security Audits	Protect infrastructure and sensitive data
Plan Review	Prevent unintended changes
Automation	Scheduled maintenance and drift detection

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If you want, I can create a visual diagram of Terraform maintenance workflow like Kubernetes control plane diagram: showing CLI → Providers → Modules → Resources → State → Upgrades → Drift detection → Security → CI/CD. It will make it very easy to teach or document for a team.

Do you want me to create that diagram?