Kubernetes etcd Alternative

Author

Bibin Wilson
December 26, 2024

In Kubernetes, etcd is the main component for storing data. It’s a reliable key-value store that keeps Kubernetes running by managing cluster state and configurations.

But did you know there are other options besides etcd?

Lightweight Kubernetes distributions like k3s make this possible.

K3s, a lightweight Kubernetes distribution, gives you these choices for storing data:

  1. Embedded SQLite: Great for temporary clusters, like those used in CI/CD pipelines.

  2. PostgreSQL

  3. MySQL

  4. MariaDB

How Does K3s Make This Work?

K3s uses Kine (Kine is not etcd), a tool that acts like a translator.

Kine converts etcd API requests into SQL queries for databases like SQLite, PostgreSQL, MySQL, and MariaDB.

It implements the etcd API but stores data in SQL instead of etcd's typical storage format.

This lets you use these databases instead of etcd, which can be easier for teams familiar with SQL.

Common Use Cases

Following are the common use cases for kine.

  1. Single-node Kubernetes deployments: In traditional Kubernetes, etcd requires multiple nodes for high availability (typically 3 or 5 nodes). For single-node deployments, this overhead is unnecessary

  2. Edge computing: Edge computing often involves running workloads on resource-constrained devices. Kine works well with limited resources (can run with <1GB memory) with simpler networking requirements.

  3. K3s: it is a lightweight Kubernetes distribution designed for IoT devices, Edge computing, Development environments and CI/CD pipelines. It uses Kine as its default storage backend.

Repository:

GitHub - k3s-io/kine: Run Kubernetes on MySQL, Postgres, sqlite, dqlite, not etcd.

Run Kubernetes on MySQL, Postgres, sqlite, dqlite, not etcd. - k3s-io/kine

github.com/k3s-io/kine

Reply

or to participate.