Tell about a complex case from your practice.

One of the complex cases in my practice involved migrating a critically important service to a new infrastructure without stopping user operations.

Task:

• Migrate the service from an outdated physical server to the cloud.
• Ensure zero downtime and maintain data integrity.

Problems:

• The service was actively working with a database, with data constantly being updated.
• It was not possible to simply shut down the service during migration.

Solution:

• Set up real-time database replication to the new platform.
• Used blue-green deployment for gradual traffic switching.
• Organized monitoring and automatic rollback in case of issues.

As a result, the migration was successful, users did not notice any changes, and the service performance even improved.

This case demonstrated the importance of thorough planning, process automation, and testing in DevOps practices.