The ipvs proxier was figuring out LoadBalancerSourceRanges matches in the nat table and using KUBE-MARK-DROP to mark unmatched packets to be dropped later. But with ipvs, unlike with iptables, DNAT happens after the packet is "delivered" to the dummy interface, so the packet will still be unmodified when it reaches the filter table (the first time) so there's no reason to split the work between the nat and filter tables; we can just do it all from the filter table and call DROP directly. Before: - KUBE-LOAD-BALANCER (in nat) uses kubeLoadBalancerFWSet to match LB traffic for services using LoadBalancerSourceRanges, and sends it to KUBE-FIREWALL. - KUBE-FIREWALL uses kubeLoadBalancerSourceCIDRSet and kubeLoadBalancerSourceIPSet to match allowed source/dest combos and calls "-j RETURN". - All remaining traffic that doesn't escape KUBE-FIREWALL is sent to KUBE-MARK-DROP. - Traffic sent to KUBE-MARK-DROP later gets dropped by chains in filter created by kubelet. After: - All INPUT and FORWARD traffic gets routed to KUBE-PROXY-FIREWALL (in filter). (We don't use "KUBE-FIREWALL" any more because there's already a chain in filter by that name that belongs to kubelet.) - KUBE-PROXY-FIREWALL sends traffic matching kubeLoadbalancerFWSet to KUBE-SOURCE-RANGES-FIREWALL - KUBE-SOURCE-RANGES-FIREWALL uses kubeLoadBalancerSourceCIDRSet and kubeLoadBalancerSourceIPSet to match allowed source/dest combos and calls "-j RETURN". - All remaining traffic that doesn't escape KUBE-SOURCE-RANGES-FIREWALL is dropped (directly via "-j DROP"). - (KUBE-LOAD-BALANCER in nat is now used only to set up masquerading) |
||
---|---|---|
.github | ||
api | ||
build | ||
CHANGELOG | ||
cluster | ||
cmd | ||
docs | ||
hack | ||
LICENSES | ||
logo | ||
pkg | ||
plugin | ||
staging | ||
test | ||
third_party | ||
vendor | ||
.generated_files | ||
.gitattributes | ||
.gitignore | ||
.golangci.yaml | ||
CHANGELOG.md | ||
code-of-conduct.md | ||
CONTRIBUTING.md | ||
go.mod | ||
go.sum | ||
LICENSE | ||
Makefile | ||
Makefile.generated_files | ||
OWNERS | ||
OWNERS_ALIASES | ||
README.md | ||
SECURITY_CONTACTS | ||
SUPPORT.md |
Kubernetes (K8s)

Kubernetes, also known as K8s, is an open source system for managing containerized applications across multiple hosts. It provides 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 your company 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 K8s
See our documentation on kubernetes.io.
Try our interactive tutorial.
Take a free course on Scalable Microservices with Kubernetes.
To use Kubernetes code as a library in other applications, see the list of published components.
Use of the k8s.io/kubernetes
module or k8s.io/kubernetes/...
packages as libraries is not supported.
To start developing K8s
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.
mkdir -p $GOPATH/src/k8s.io
cd $GOPATH/src/k8s.io
git clone https://github.com/kubernetes/kubernetes
cd 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.
Community Meetings
The Calendar has the list of all the meetings in Kubernetes community in a single location.
Adopters
The User Case Studies website has real-world use cases of organizations across industries that are deploying/migrating to Kubernetes.
Governance
Kubernetes project is governed by a framework of principles, values, policies and processes to help our community and constituents towards our shared goals.
The Kubernetes Community is the launching point for learning about how we organize ourselves.
The Kubernetes Steering community repo is used by the Kubernetes Steering Committee, which oversees governance of the Kubernetes project.
Roadmap
The Kubernetes Enhancements repo provides information about Kubernetes releases, as well as feature tracking and backlogs.