Docker vs Flocker: What are the differences?

Introduction

Docker and Flocker are both technologies used in the field of containerization. While Docker focuses on creating and managing isolated containers, Flocker aims to enable the portability and data persistence of containers.

1. Portability: Docker provides a highly portable environment by packaging applications and their dependencies into containers. These containers can be run on any system that supports Docker, making it easy to deploy applications across different environments. On the other hand, Flocker goes beyond container portability by allowing the movement of containers along with their associated data across different hosts or clusters.

2. Data Management: Docker containers are designed to be stateless, meaning they do not store data persistently. Flocker, however, addresses this limitation by providing container-level data management. It allows data volumes to be moved and associated with containers, ensuring data persistence and availability even when containers are moved to different hosts.

3. Scalability: Docker's focus is on container orchestration and management, making it highly scalable. It provides features like automatic scaling, load balancing, and service discovery. Flocker, on the other hand, primarily focuses on data management and portability, and does not offer built-in scalability features. However, Flocker can be used in conjunction with container orchestration platforms like Kubernetes to achieve scalability.

4. Multi-Host Support: Docker primarily operates on a single host, with containers running independently on that host. Flocker, in contrast, supports multi-host deployments and allows the movement of containers and their associated data across different hosts or clusters. This enables distributed applications and data to be managed effectively.

5. Data Consistency: Docker containers are typically isolated from each other and do not share a common data source. Flocker provides a mechanism for managing data consistency across containers by enabling the movement of data volumes along with the containers. This ensures that containers always have access to the latest and consistent data.

6. Use Cases: Docker is widely used for application development, deployment, and scaling. It is commonly used by developers to package their applications and dependencies into containers for easy distribution and deployment. Flocker, on the other hand, is primarily used in scenarios where data persistence and portability are critical, such as database clusters and stateful applications.

In summary, Docker focuses on providing a highly portable and scalable environment for containerized applications, while Flocker emphasizes on data persistence and portability across hosts or clusters.