In December 2016, Solomon Hykes, the founder of Docker, announced a re-focused containerd (Con-tay-ner-D) initiative, spinning out the core container runtime from the Docker Engine community project. At the time, it wasn't entirely clear where containerd would land, but now the picture has come into focus, as Docker is sending containerd to the Cloud Native Computing Foundation (CNCF).
"We already have an investment in the CNCF, and it made sense to take advantage of that existing investment," Hykes told ServerWatch.
Docker Inc was among the founding members of the Cloud Native Computing Foundation (CNCF), which got started in July 2015 as a Linux Foundation Collaboration Project. Hykes noted that Docker already has technical integrations with several projects hosted by CNCF, including the Prometheus monitoring project and the GRPC remote procedure call effort.
"We had a lot of informal conversations in the last few months, and there was a lot of demand for us to donate containerd to CNCF," Hykes said. "So we're responding to requests with this."
CoreOS rkt Set to Launch to the CNCF Soon As Well?
The Docker containerd effort isn't the only container runtime effort that might be headed to the CNCF. Docker rival CoreOS could well soon be sending its rkt (pronounced Rocket) container runtime to the CNCF soon too.
"As container execution engines, rkt and containerd are similar projects, but follow very different architectural/design choices," CoreOS developer Jonathan Boulle wrote in his request for the CNCF to consider rkt. "At the same time, they strive for broader compatibility with each other and the ecosystem by implementing and working with standards like those developed in OCI or integrating with Kubernetes."
The Open Container Initiative (OCI) was originally started in June 2015 as a way to develop a standard specifications for containers. CoreOS split from the mainline Docker community in December of 2014, launching its rkt (Rocket) container technology as an alternative to Docker. The OCI effort was intended to help be a bridge of sorts, creating a vendor-neutral base specification.
Hykes said he wasn't all that surprised CoreOS has announced it wants to donate rkt to CNCF. That said, he emphasized that he is focused on making containerd the best it can be in an open model, which CNCF will help to further enable.
"Everyone is focused on making their respective projects succeed," Hykes said.
Forecasting the Future of Kubernetes Container Management and Orchestration
Among the core projects at the CNCF is the open-source Kubernetes container management and orchestration effort, which is competitive with Docker's own open-source Swarm project. But Hykes doesn't see Swarm as necessarily being a competitor to Kubernetes for a variety of reasons.
"Currently, Docker uses Swarm, but we're also making sure that containerd can use Kubernetes, and we expect that containerd will become the de facto container runtime for all Kubernetes users," Hykes said. "So that will bring in a lot of contributions to containerd, through the Kubernetes community."
Hykes also sees the inclusion of containerd in the CNCF as an opportunity to help improve collaboration between the Swarm and Kubernetes communities. Today there is no standard policy language that can enable both Swarm and Kubernetes, such that a one-policy approach could work with both systems.
Patrick Chanezon, chief developer advocate at Docker Inc, noted that past efforts in other areas of policy co-ordination in IT, including the WS-Coordination effort for web services didn't work out. In his view, with containers, it makes sense now to standardize the runtime, but it's too early to look at a standardized policy language for orchestration.
Hykes expects that over time there will be a convergence on container orchestration across the different systems, including Swarm, Kubernetes and mesos, with some form of interoperability.
The containerd effort is moving along rapidly, and the current roadmap plan has a 1.0 release set for June 2017.
Sean Michael Kerner is a senior editor at ServerWatch and InternetNews.com. Follow him on Twitter @TechJournalist.