Probably the hottest area in building next generation applications these days is microservices, running on containers. One key challenge with containers has been that they do not allow persistent data. Enter ClusterHQ which addresses it with its Flocker offering, that just become available today.
Docker containers get persistent with Flocker by ClusterHQ.
Let’s dissect the press release in our customary style (the press release can be found here):

SAN FRANCISCO – June 17, 2015 – ClusterHQ, The Container Data People, today announced the general availability of Flocker 1.0, its container data management software. By enabling stateful Docker containers to be easily moved between servers, Flocker facilitates widespread production deployment of containers for databases, queues and key value stores. Modern applications are being built from both stateless and stateful microservices; Flocker makes it simple and practical for entire applications, including their state, to be containerized to take full advantage of the portability and massive per-server density benefits inherent in containers. This operational freedom allows DevOps organizations to increase the value of their Docker investment and opens the door for containers to be used in a greater variety of mainstream enterprise use cases in production. Flocker 1.0 is available as an Apache-licensed download at

MyPOV – Good to see support for databases, but also queues and value stores. Many next generation application use cases go beyond traditional databases and use queues and / or (named) value stores. Rightfully ClusterHQ stresses that more use cases become possible now for containers. And no surprise, Flocker is open source, Apache license.

“Containers are emerging as one of the most important innovations in modern computing since virtualization. Forward-thinking developers and organizations are latching onto this phenomenon for good reason. Containers are revolutionizing how microservice-based applications are built and operated, by delivering orders of magnitude better density, and unprecedented portability of applications. By making it possible for containers and their data volumes to be moved in production IT environments, innovative vendors are enabling the business benefits of containers to reach even further, removing barriers to Dockerizing everything,” noted Holger Mueller, VP and principal analyst, Constellation Research.
Empowering portability of containers and their data as a single unit, a prerequisite for many production uses, Flocker lets DevOps teams easily containerize their stateful microservices, thus consolidating their entire distributed application into an all-Docker development and operations environment. With everything running in containers, IT operations can be simplified into a unified set of operational processes. Moreover, making it easy to containerize stateful microservices decreases costs so that far more applications can be run on a given set of hardware. Because Flocker enables easy migration of stateful containers, organizations now have the flexibility to accommodate common IT processes such as routine maintenance and load balancing of workloads across servers. The downstream impact is meaningful in today’s real-time economy: businesses can innovate faster and become more responsive to their customers.

MyPOV – In most cases we have seen development organizations shying away from stateful use cases for containers. Those who pushed onwards had to orchestrate complex operations to coordinate code (in containers) and data (in a variety of storage formats) with elaborate DevOps mechanisms. And most were so complex that they hurt what most next generation applications are all about – elasticity of resources. Now there is an option to get both handled in a single product / construct with Flocker.

“Organizations use Docker to accelerate their application development lifecycle and achieve frictionless portability of their distributed applications to anywhere. ClusterHQ identified early on that running stateful services in containers would help drive Dockerized applications more rapidly into production. Their technology helps organizations that want to take advantage of Docker’s benefits for stateful as well as stateless applications.” said Nick Stinemates, head of business development and technical alliances, Docker, Inc.

MyPOV – Good for Flocker to get a quote from the 800 pound Gorilla of containers, Docker. Begs the question what Docker’s plans are here – but for now it looks like a good (informal) partnership as we often see these days.

Flocker provides an API and CLI for managing containers and data volumes, and works with multiple storage solutions including Amazon EBS, Rackspace Cloud Block Storage, any OpenStack Cinder-compatible device, EMC ScaleIO and EMC XtremIO. The pluggable nature of Flocker is designed to work with any storage system, delivering the ability to integrate dockerized applications with existing storage backends. Any company or community that wants its storage to work with Docker can easily write a driver for Flocker.

MyPOV – Good to see a modularized, extensible architecture of Flocker, with pluggable drivers for different storage systems. And for those left out right now – though the initial scope delivered by Flocker is an impressive first release – they can build their own drivers. A good showcase for openness and dynamics of the open source ecosystem.

“The efficiency and operational freedom of using containers for both compute and storage create a competitive advantage so significant that smart organizations are seeking ways to containerize more of the applications that are strategic to their business. The ClusterHQ mission is to make it as easy to containerize data as it is to containerize compute,” said Mark Davis, CEO of ClusterHQ.

MyPOV – Key quote with the ClusterHQ mission – make it as easy to containerize data as it is to containerize compute.

In addition to this news, ClusterHQ today announced a partnership with EMC, as well as the compelling findings from a recent third party survey regarding current and planned adoption of container technology across organizations of all sizes. To learn more about the EMC partnership; to access the survey and report visit: […]

MyPOV – Good to see ClusterHQ getting the interest of storage heavy weight EMC. And likewise good to see that EMC is looking at this dynamic ecosystem, which could disrupt how the storage market operates.

Overall MyPOV

Good to see a vibrant microservices ecoystem. Even better to see vendors like ClusterHQ tackling tough and crucial capabilities that expand the use cases that can be automated with container based next generation applications. From my (more enterprise software formed) experience and network, the majority of use cases are in a persistent world. If you can't make a business process persistent, it may well not have happened. So making containers persistent is probably an increase of 3-5x uses cases that can be addressed by containers that have persistency.

On the concern side, this is early days, not a trivial problem to solve, so it will be key to see first use cases and the success of early adopters. And it needs to work, reliably, 24x7. It also raises the ante for containers themselves - because users cannot just start another 'container engine' to replace one that has gone bad, but if a container crashes, state is lost. And that is not a good outcome for most use cases.

But overall congrats to ClusterHQ for providing a key capability to Docker with Flocker. Major step, we will be watching the adoption.