A month ago today, Docker Inc. joined with its container rivals in a new Linux Foundation effort, known as the Open Container Project. The name of the effort is now being changed to the Open Container Initiative (OCI) as the membership rolls swell and development efforts to build and define a common baseline for containers accelerates.
Membership in OCI now includes AT&T, ClusterHQ, Datera, Kismatic, Kyup, Midokura, Nutanix, Oracle, Polyverse, Resin.io, Sysdig, SUSE, Twitter and Verizon. The new members join the founding members, which include Docker Inc., CoreOS, Amazon Web Services, Apcera, Cisco, EMC, Fujitsu, Goldman Sachs, Google, HP, Huawei, IBM, Intel, Joyent, the Linux Foundation, Mesosphere, Microsoft, Pivotal, Rancher Labs, Red Hat and VMware.
The Linux Foundation discovered after the initial Open Container Project (OCP) launch announcement that there was some form of name conflict, which is why it is changing the name to OCI.
While the OCI is only 30 days old, Patrick Chanezon, member of the technical staff at Docker Inc., said that significant progress has been made on the technical front. OCIs core goal is to help define and build a baseline for containers that enables interoperability. Prior to the creation of OCI, there was some doubt in the open-source community about container interoperability with a rift between Docker and those that were backing the appc specification led by CoreOS.
"The OCI format specification defines the container format, which includes the file system that the container image is based on as well as the configuration parameters for a tool to create the container," Chanezon said. "So the specification is one level down from where both Docker and appc are sitting."
Chanezon said that people from both the appc and Docker communities have been working together for the last month, taking the best ideas from both approaches and bringing them to the OCI.
At the core of OCI is technology called libcontainer, which had been part of Docker. Inside libcontainer is a component called nsinit, which has now been renamed runc. As part of the OCI effort, two concurrent efforts are being worked on and are publicly visible on Github: the specs effort to define the Open Container specification and runc, which is the implementation of the specs.
"The spec really tries to be a multi-operating system approach," Chanezon said.
It's still early in the process for the OCI specification, but the goal is to have the first official draft available within the next two to three weeks. It will be complemented by a version of runc that implements the specification, Chanezon said. It will likely take a few months for the specification to settle and reach a possible 1.0 status, he added.
So far, those involved in OCI have been working well together, Chanezon said. "There has been no squabbling or disputes in the working group; it has just been a super productive group of developers working together," Chanezon said. "What helps is that a lot of the developers had already been working together with libcontainer, so they already had a working cadence."
Sean Michael Kerner is a senior editor at eWEEK and InternetNews.com. Follow him on Twitter @TechJournalist.