KubeCon + CloudNativeCon North America 2024

Kubernetes relies on API data being actively rewritten to support some maintenance activities related to at-rest storage. Two prominent examples are the versioned schema of stored resources (i.e., the preferred storage schema changing from v1 to v2 for a given resource) and encryption at rest (i.e., rewriting stale data based on a change in how the data should be encrypted). The simplest way to rewrite data is to issue no-op update requests via kubectl. This approach is problematic for any resource that can contain a large amount of data, such as Kubernetes secrets, and it is also impractical to perform without automation, as the number of resources that need migration is always growing. Storage Version Migration (SVM), which is now available as a built-in alpha API since Kubernetes v1.30, helps achieve this. However, the implementation of SVM has significant implications for the entire Kubernetes project and its ecosystem.