|
|
|
|
|
|
by gtirloni
3554 days ago
|
|
|
I've a hard time positioning this along side the effort to support rkt in Kubernetes. Would OCID be necessary because there's too much Docker-only code to interface with the container runtime in Kubernetes? I think I expected rkt to be fully OCI compatible in the future but it looks like Kubernetes itself needs to be able to interface with OCI runtimes and there's work to be done in that area? The Docker integration cuts too deep currently? |
|
|
As for Kubernetes rkt support: it is usable today and continues to develop nicely. If you want to try it out on your laptop it is super easy with minikube: https://tectonic.com/blog/minikube-and-rkt.html
Overall, the rkt support is in a good spot, works today, and the team is working on how to make all of the corners of Kubernetes work flawlessly. And it will support all of the parts of OCI as that specification matures.
If people are interested in joining in and adding a runc backend to rkt that would be great. However, all of the pieces needed to support Kubernetes is already there so we haven't seen much reason to do it. Inside of rkt there is an abstraction called a "stage1" that enables swaping out of the actual containerization system. This is what has enabled us to support Virtual Machine "wrapped" containers[1] inside of rkt for a long time.
For some more background on this article in particular. Folks in the community working at Google, CoreOS, and Red Hat have been working on a container runtime interface[2]. This interface is helping the Kubernetes team refactor the code that currently interfaces with Docker and rkt into a cleaner subsystem. As part of that effort the team is also exposing a gRPC interface to enable various implementations and experimentation. This is the interface the team at Red Hat building cri-o (formerly OCID) is using.
[0] https://groups.google.com/a/opencontainers.org/forum/#!topic...
[1] https://coreos.com/rkt/docs/latest/running-lkvm-stage1.html
[2] https://github.com/kubernetes/kubernetes/blob/master/docs/pr...