Last week, I had a conversation with a DevOps leader from a $15B public company around “migration” or, in this case, “Cloud re-hosting.” We concluded that most migrations are done wrong. His solution was to go for “gradual” migration. Here are 5 highlights from his approach.

Background

Organizations face many challenges while migrating applications from one cloud to another, ranging from data gravity, vendor lock-in, and the need to minimize application downtime. Traditional approaches can be disruptive and costly, so exploring strategic, phased methods is essential.

Key Takeaways

1. Use an Overlay Network: No change to application code is needed. This is a standout benefit. It ensures that microservices are automatically migrated to the destination cloud cluster upon each deployment in the source cloud cluster.
2. Implement a Service Gateway: Deploy a service gateway to have seamless connectivity to managed services in the source cloud provider by services in the destination cloud cluster. Here too, no change to application code is needed. Access achieved only using YAML files.
3. No Changes to Application Code: When services are to communicate with other services in a service chain that are deployed across clouds, enabling this communication without any change to application code is “magic.” This ensures uninterrupted development workflows during the migration process.
4. Maintain Connectivity to Source Code: Another standout benefit of this “gradual” migration approach, is that the moved microservices in the destination cloud can still communicate with the services left behind in the original cloud provider. This ensures continuous application uptime during the migration process.
5. Immediate Cost Reduction: Cost efficiency from day one is the primary motivator for this kind of migration strategy. While some services must stay in hyper-scaler clouds, others can be gradually moved to more cost-effective clouds. This allows for incremental workload migration and enables the moved workloads to be made to work natively in the destination environment.

Our conversation reinforced the idea that moving workloads from one cloud to another (call it cloud re-hosting or workload migration) doesn't have to be an all-or-nothing endeavor. With the right tools and strategy, businesses can optimize their infrastructure and reduce costs in a phased, controlled manner.