Disaster recovery strategies in GCP - Commands & Configuration

Introduction

Disaster recovery strategies help you prepare for unexpected problems like data loss or system failures. They make sure your cloud services can quickly recover and keep running with minimal downtime.

When you want to protect your important data from accidental deletion or corruption.

When you need to keep your website or app running even if one cloud region goes down.

When you want to quickly restore your services after a natural disaster or cyber attack.

When you want to test your backup and recovery plans regularly to avoid surprises.

When you want to meet compliance rules that require data protection and recovery plans.

Config File - main.tf

main.tf

provider "google" {
  project = "example-project"
  region  = "us-central1"
}

resource "google_compute_disk" "primary_disk" {
  name  = "primary-disk"
  type  = "pd-standard"
  zone  = "us-central1-a"
  size  = 50
}

resource "google_compute_disk" "backup_disk" {
  name  = "backup-disk"
  type  = "pd-standard"
  zone  = "us-east1-b"
  size  = 50
}

resource "google_compute_snapshot" "disk_snapshot" {
  name       = "primary-disk-snapshot"
  source_disk = google_compute_disk.primary_disk.id
}

resource "google_storage_bucket" "backup_bucket" {
  name     = "example-backup-bucket"
  location = "US"
  versioning {
    enabled = true
  }
}

This Terraform file sets up a primary disk in one zone and a backup disk in another zone for disaster recovery. It creates a snapshot of the primary disk to capture its state. It also creates a storage bucket with versioning enabled to store backups safely.

This setup helps recover data if the primary disk or zone fails.

Commands

This command initializes Terraform in the current directory. It downloads the Google provider plugin and prepares Terraform to manage resources.

Terminal

terraform init

Expected Output

Initializing the backend...



Initializing provider plugins...

- Finding latest version of hashicorp/google...

- Installing hashicorp/google v4.0.0...

- Installed hashicorp/google v4.0.0 (signed by HashiCorp)



Terraform has been successfully initialized!

This command applies the Terraform configuration to create the resources defined in the file. The -auto-approve flag skips the confirmation prompt.

Terminal

terraform apply -auto-approve

Expected Output

google_compute_disk.primary_disk: Creating...

google_compute_disk.backup_disk: Creating...

google_compute_disk.primary_disk: Creation complete after 10s [id=projects/example-project/zones/us-central1-a/disks/primary-disk]

google_compute_disk.backup_disk: Creation complete after 10s [id=projects/example-project/zones/us-east1-b/disks/backup-disk]

google_compute_snapshot.disk_snapshot: Creating...

google_compute_snapshot.disk_snapshot: Creation complete after 5s [id=projects/example-project/global/snapshots/primary-disk-snapshot]

google_storage_bucket.backup_bucket: Creating...

google_storage_bucket.backup_bucket: Creation complete after 3s [id=example-backup-bucket]



Apply complete! Resources: 5 added, 0 changed, 0 destroyed.

→

-auto-approve - Automatically approve the apply without asking for confirmation

This command lists the snapshot created for the primary disk to verify it exists and is ready for recovery.

Terminal

gcloud compute snapshots list --filter="name=primary-disk-snapshot"

Expected Output

NAME                   DISK_NAME      STATUS    CREATION_TIMESTAMP

primary-disk-snapshot  primary-disk  READY     2024-06-01T12:00:00.000-07:00

→

--filter - Filter the list to show only snapshots with the specified name

This command lists the contents and details of the backup storage bucket to confirm backups are stored with versioning.

Terminal

gsutil ls -L gs://example-backup-bucket

Expected Output

gs://example-backup-bucket/: 

    Storage class: STANDARD

    Location constraint: US

    Versioning enabled: True

    Time created: 2024-06-01T11:50:00.000Z

    Labels: None

    Lifecycle: None

    Cors: None

    Logging: None

    Website: None

    Encryption: None

    Retention policy: None

    Default event-based hold: False

    Bucket Policy Only: Disabled

    Uniform bucket-level access: Disabled

    Public access prevention: Unspecified

    Default KMS key: None

    Requester Pays: Disabled

    Owner: [e-mail]

    Project number: 123456789012

Key Concept

If you remember nothing else from this pattern, remember: regularly create backups and store them in a separate location to recover quickly from disasters.

Common Mistakes

Not enabling versioning on the backup storage bucket

Without versioning, you cannot recover previous versions of files if they are overwritten or deleted.

Always enable versioning on backup buckets to keep multiple versions of your data.

Creating snapshots only in the same zone as the primary disk

If the entire zone fails, snapshots in the same zone may be lost or inaccessible.

Store snapshots or backups in a different zone or region to ensure availability during zone failures.

Not verifying backups after creation

Backups might fail silently or be incomplete, leading to failed recovery when needed.

Regularly check and test your backups and snapshots to confirm they are complete and usable.

Summary

Initialize Terraform to prepare for resource management with 'terraform init'.

Apply the configuration to create disks, snapshots, and backup storage with 'terraform apply'.

Verify snapshots exist using 'gcloud compute snapshots list' to ensure recovery points.

Check backup storage bucket details with 'gsutil ls -L' to confirm versioning and data safety.