The bloom may be off the rose for the darling of the Linux container world.
Docker Inc. turned 3 years old this month, and has achieved a lot in a very short time: 2 billion pulls, $160 million in venture funding and several acquisitions. Beloved by developers, Docker is rapidly making inroads into production IT environments. But for all that success, there is growing concern the company is trying to do too much, too soon, and is alienating would-be users and partners.
Docker's bread and butter is its container format and the core Docker Engine for building and running Docker containers. But its products don't end there, by any means: There's Docker Registry, for image registration; Docker Compose, for defining multicontainer applications; Docker Swarm host clustering and scheduling; and Docker Machine, for automated container provisioning. Then, there are two hosted registries -- Docker Hub and Docker Trusted Registry -- plus the new Docker Datacenter, Docker Cloud and Universal Control Plane.
Getting to market quickly, with a wide range of products is all part of the Docker strategy, according to Scott Johnston, COO at Docker, based in San Francisco.
"The idea is to focus on the horizontal, with a platform that goes broad, then circle back and provide a hardened stack," he said.
Some industry observers think that's the right tack, if Docker wants to appeal not just to developers, but to IT as a whole.
"That's exactly what needs to happen," said Chris Riley, DevOps analyst with Fixate IO, based in Livermore, Calif. "Docker has really suffered from the problem of being built by developers for developers, and bottom-up adoption."
Developers who have used Docker's open source products for free don't have enough "skin in the game" to force enterprisewide adoption of the technology, which is where it must go next to have long-term success, Riley said.
But early attempts at charging for its products have fallen flat -- witness the reaction to pricing for Docker Cloud among the existing user base.
"A lot of startups do themselves an injustice when they give away the farm," Riley said. "So, they have to expect that fallout and deal with that."
A need for speed
Some feel that a bigger problem for Docker is that it's moving too fast.
XtremIO, an all-flash storage provider owned by EMC, recently put together a proof of concept of its system working in a containerized environment for a large banking customer. It used Mesosphere and Marathon for scheduling and orchestration, rather than Docker Swarm, said Itzik Reich, XtremIO CTO. "What they wanted was a working solution," he said. "Swarm is not there from a scaling perspective."
At the same time, expansion in so many different areas stretches Docker too thin, according to some observers.
"There's been inertia across a lot of projects, where the number of pull requests is down, or the teams are not as responsive as they used to be," said Aaron Welch, co-founder and SVP at Packet, a New York-based bare-metal cloud provider whose customers are big users of containers.
Meanwhile, Docker's core products also aren't being developed as fast as they could be.
"Things like Dockerfiles could probably have more functionality and move away from some of the monoliths that they have," said Pauly Comtois, vice president of DevOps for a multinational media company.
Comtois is a "big fan" of Docker, but "they took a period of time where they started to move outside their core competencies, rather than focusing on continuing to mature the core product."
It makes sense from a business standpoint that Docker is going after enterprises with products such as Datacenter, Welch said, but "I don't know a lot of companies that can grow so quickly in so many directions and just knock it out of the park."
Partners feel the pinch
Further, Docker's rush to get products out the door creates problems for partners to work with them, said Jeff Behl, chief network architect at LogicMonitor Inc., based in Santa Barbara, Calif., a maker of hosted monitoring software that is building in support for Docker in its system. Between Docker version 1.8 to 1.10, "there was no backward compatibility," he said. "It's been a pain."
Docker partners have felt the squeeze for several months.
"I first started to feel it at DockerCon Barcelona," back in November, said Zachary Smith, CEO at Packet. "[Docker] was telling everyone, 'Don't talk about Kubernetes!' and I thought to myself, 'That's weird.'”
This attitude also has cast a pall on venture capital tied to Docker, Smith said, for fear of investing in companies whose products could be replicated by Docker. For instance, there's speculation that Docker could release a VMware VSAN-like software-defined storage service, which would compete with container storage startups, such as Rancher Labs and Portworx.*
Instead, VCs investing in this space warn startups to align themselves with Google Kubernetes, Mesosphere or HashiCorp. "There's definitely a halo around Kubernetes and Google Cloud Platform," Smith said, because it's clear where that ecosystem is headed.
Docker declined requests for further comment.
* - Statement changed after initial publication.
Alex Barrett is the editor in chief for TechTarget's Modern Infrastructure e-zine. Write to her at firstname.lastname@example.org.
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