Fix Terraform Error: Error Acquiring the State Lock Timeout Exceeded

# Check if another terraform process is running
ps aux | grep terraform
 
# If no process is running, force unlock
terraform force-unlock LOCK_ID

Error: Error acquiring the state lock
 
Error message: ConditionalCheckFailedException: The conditional request failed
Lock Info:
  ID:        a1b2c3d4-e5f6-7890-abcd-ef1234567890
  Path:      my-bucket/prod/terraform.tfstate
  Operation: OperationTypeApply
  Who:       user@machine
  Version:   1.9.0
  Created:   2026-04-12 10:30:00.000000000 +0000 UTC
 
Terraform acquires a state lock to protect against two processes
writing to the state at the same time. The lock was not released
within the configured timeout period.

# Check who holds the lock (shown in error message)
# Who: user@machine — ask that person
 
# Retry with a longer timeout
terraform apply -lock-timeout=10m

# Copy the Lock ID from the error message
terraform force-unlock a1b2c3d4-e5f6-7890-abcd-ef1234567890

# Local machine
ps aux | grep terraform
 
# CI/CD — check running pipelines in GitLab/GitHub
 
# Check DynamoDB directly (S3 backend)
aws dynamodb scan \
  --table-name terraform-locks \
  --filter-expression "LockID = :id" \
  --expression-attribute-values '{":id":{"S":"my-bucket/prod/terraform.tfstate"}}'

apply-prod:
  stage: deploy
  resource_group: terraform-prod   # Only one job at a time
  script:
    - terraform apply -auto-approve -lock-timeout=5m

jobs:
  apply:
    concurrency:
      group: terraform-prod
      cancel-in-progress: false    # Don't cancel running applies!
    steps:
      - run: terraform apply -auto-approve

# Default timeout is 0s (fail immediately)
# Set a reasonable timeout for team environments
terraform apply -lock-timeout=5m
terraform plan -lock-timeout=5m

export TF_CLI_ARGS_apply="-lock-timeout=5m"
export TF_CLI_ARGS_plan="-lock-timeout=5m"

terraform {
  backend "s3" {
    bucket         = "my-terraform-state"
    key            = "prod/terraform.tfstate"
    region         = "us-east-1"
    dynamodb_table = "terraform-locks"   # This enables locking
    encrypt        = true
  }
}
 
# Create the lock table
resource "aws_dynamodb_table" "terraform_locks" {
  name         = "terraform-locks"
  billing_mode = "PAY_PER_REQUEST"
  hash_key     = "LockID"
 
  attribute {
    name = "LockID"
    type = "S"
  }
}