f90bbc3d6b
The `certificate_expiration_seconds` histogram measures the remaining time of client certificates used to authenticate to the API server. It records the lifetime of received client request certificates in buckets of 6h, 12h, ..., 1y. In environments with automated certificate rotation it is not uncommen to have issued certificates expire in less than the above mentioned minimum bucket of 6h. In such environments the above histogram is useless given that every request will be recorded in the first bucket. This patch increases the histogram resolution by adding a 30m, 1h and 2h bucket. Prometheus histogram buckets are cummulative, e.g. the 12h bucket is counting _all_ records with an expiration date lower or equal to 12h including _all_ requests of the 6h bucket. Thereby this patch does not break existing monitoring setups. This histogram is exposed once per API server, thereby the 3 additional time series do not cause a cardinality issue.
Kubernetes
Kubernetes is an open source system for managing containerized applications across multiple hosts; providing basic mechanisms for deployment, maintenance, and scaling of applications.
Kubernetes builds upon a decade and a half of experience at Google running production workloads at scale using a system called Borg, combined with best-of-breed ideas and practices from the community.
Kubernetes is hosted by the Cloud Native Computing Foundation (CNCF). If you are a company that wants to help shape the evolution of technologies that are container-packaged, dynamically-scheduled and microservices-oriented, consider joining the CNCF. For details about who's involved and how Kubernetes plays a role, read the CNCF announcement.
To start using Kubernetes
See our documentation on kubernetes.io.
Try our interactive tutorial.
Take a free course on Scalable Microservices with Kubernetes.
To start developing Kubernetes
The community repository hosts all information about building Kubernetes from source, how to contribute code and documentation, who to contact about what, etc.
If you want to build Kubernetes right away there are two options:
You have a working Go environment.
$ go get -d k8s.io/kubernetes
$ cd $GOPATH/src/k8s.io/kubernetes
$ make
You have a working Docker environment.
$ git clone https://github.com/kubernetes/kubernetes
$ cd kubernetes
$ make quick-release
For the full story, head over to the developer's documentation.
Support
If you need support, start with the troubleshooting guide, and work your way through the process that we've outlined.
That said, if you have questions, reach out to us one way or another.