Migrating from Azure to Google Cloud Platform (GCP) or vice versa involves several key steps to ensure a smooth and efficient transition. Here’s a general overview of the process for both directions:

Azure to GCP Migration:

1. Assess the Azure Environment: Analyze your current Azure setup to identify workloads, applications, their dependencies, and interdependencies.
2. Choose a Migration Strategy: Decide on a suitable approach like rehosting, refactoring, or rebuilding based on the assessment.
3. Prepare the GCP Environment: Set up the necessary configurations on GCP, ensuring compatibility with the Azure workloads.
4. Migrate Data: Utilize tools like Google Cloud Platform Transfer Service for secure data transfer from Azure to GCP.
5. Migrate Applications: Tools like Google Cloud Platform Migrate for Compute Engine can assist in moving applications, with post-migration testing for performance and reliability.
6. Optimize the GCP Environment: Fine-tune for performance, security, cost, and compliance.

GCP to Azure Migration:

1. Assess the GCP Environment: Similar to Azure to GCP, begin by analyzing your GCP environment.
2. Choose a Migration Strategy: Based on the assessment, select the appropriate strategy.
3. Prepare the Azure Environment: Set up Azure with the required configurations for GCP workloads.
4. Migrate Data: Azure Data Factory or similar tools can be used for migrating data from GCP to Azure.
5. Migrate Applications: Azure Site Recovery and other tools can help in moving applications, followed by testing.
6. Optimize the Azure Environment: Post-migration, optimize for various factors like performance and security.

It’s important to note that migrating cloud services is a complex process and requires careful planning and execution. The choice of tools and the specific steps may vary based on the individual requirements and configurations of your existing setup.

For more detailed guidance, you can refer to the sources I used: UnoGeeks and A for Analytics. Additionally, NetApp offers insights into Google Cloud Migration with a specific focus on migrating from an on-premises data center to Google Cloud, which might be useful in understanding the overall cloud migration landscape.