GCP to Azure

Migrating from Google Cloud Platform (GCP) to Microsoft Azure requires careful planning, mapping of services, and process adaptation. This guide provides actionable steps, real-life examples, and best practices for a successful migration.

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Quick Comparison: GCP vs Azure Services

GCP Service	Azure Equivalent	Notes
Compute Engine	Virtual Machines (VMs)	VM types and images differ
Cloud Storage	Blob Storage	APIs and access models vary
Cloud IAM	Azure Active Directory	RBAC and identity federation differ
Cloud SQL	Azure SQL Database	Migration tools available
Cloud Functions	Azure Functions	Triggers and bindings differ
Deployment Manager	ARM Templates/Bicep	Syntax and capabilities differ
Stackdriver Monitoring	Azure Monitor	Metrics and logging integration varies
VPC	Virtual Network (VNet)	Subnet and peering models differ
GKE (Kubernetes Engine)	AKS (Azure Kubernetes)	Cluster management differs
Cloud DNS	Azure DNS	Record types and automation differ

Tip: Microsoft's GCP to Azure service mapping

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Migration Checklist

• Inventory GCP Resources Use gcloud CLI: gcloud asset search-all-resources --format=json > gcp-inventory.json

• Map GCP Services to Azure Equivalents Create a mapping table for all services in use.

• Assess Application Dependencies Identify hardcoded endpoints, region-specific services, and OS dependencies.

• Plan Identity and Access Migration Prepare to migrate Cloud IAM users/groups to Azure AD.

• Network Planning Design Azure VNets to match or improve your GCP VPC topology.

• Translate Infrastructure as Code Convert Deployment Manager templates to ARM/Bicep or Terraform.

• Migrate Data Use AzCopy or Storage Transfer Service for storage migration.

• Migrate Identity Set up Azure AD, and test user access.

• Refactor Applications Update code/configs to use Azure SDKs and endpoints.

• Test and Validate Use Azure Monitor and Application Insights for validation.

• Update DNS Point domains to Azure endpoints (Azure DNS).

• Monitor and Optimize Use Azure Cost Management and Azure Advisor.

• Decommission GCP Resources Confirm all data is migrated and backups are complete before deleting.

• Update Documentation Revise runbooks and architecture diagrams.

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Migration Steps (with Examples)

1. Infrastructure as Code (IaC) Translation

• Example: Convert Deployment Manager templates to Azure Bicep or ARM templates.

  • Use dm-convert to export, then adapt to Azure.
  • Example Terraform snippet for Azure VM:

    resource "azurerm_virtual_machine" "example" {
      name                  = "example-vm"
      resource_group_name   = azurerm_resource_group.example.name
      location              = azurerm_resource_group.example.location
      # ...
    }

2. Data Migration

• Example: Migrate Cloud Storage buckets to Azure Blob Storage using AzCopy:

  azcopy copy "https://storage.googleapis.com/<bucket>" "https://<account>.blob.core.windows.net/<container>" --recursive

3. Identity Migration

• Example: Sync GCP IAM users to Azure AD using Azure AD Connect.

4. Application Refactoring

• Update code/configs to use Azure SDKs and endpoints.

• Replace GCP Cloud Functions triggers with Azure Function bindings.

5. Testing and Validation

• Use Azure Monitor and Application Insights for post-migration validation.

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Post-Migration Tasks

• Update DNS: Point domains to Azure endpoints (e.g., Azure DNS).

• Monitor and Optimize: Use Azure Cost Management and Azure Advisor.

• Decommission GCP Resources: Ensure all data is migrated and backups are complete before deleting.

• Documentation: Update runbooks and architecture diagrams.

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Best Practices & Common Pitfalls

• Start with Non-Production Workloads: Validate migration steps before moving critical systems.

• Automate Everything: Use Terraform/Ansible for repeatable deployments.

• Watch for Service Limits: Azure and GCP have different quotas.

• Security Review: Reassess security groups, NSGs, and IAM/RBAC policies.

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Cloud Hopping Humor

Why did the engineer bring a suitcase to the GCP to Azure migration?

Because they were ready for a change in the cloud forecast!

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References

• GCP to Azure Service Comparison
• Azure Migration Center
• Terraform Azure Provider Docs
• AzCopy Documentation