It can happen that a claim gets deallocated in parallel to adding a new pod to
ReservedFor. Without binding conditions, that was caught by the apiserver
validation. With binding conditions, the code which checks and sets
AllocationTimestamp panics with a nil pointer access.
This has been observed in the TestDRA/all/ShareResourceClaimSequentially
integration test, but couldn't be reproduced locally:
E0303 07:43:20.158261 39037 panic.go:262] "Observed a panic" panic="runtime error: invalid memory address or nil pointer dereference" panicGoValue="\"invalid memory address or nil pointer dereference\"" stacktrace=<
goroutine 554266 [running]:
k8s.io/apimachinery/pkg/util/runtime.logPanic({0x69ce9f0, 0xc017bc00f0}, {0x59381a0, 0x91c6570})
/home/prow/go/src/k8s.io/kubernetes/staging/src/k8s.io/apimachinery/pkg/util/runtime/runtime.go:132 +0xbc
k8s.io/apimachinery/pkg/util/runtime.handleCrash({0x69ce8d8, 0x93d87a0}, {0x59381a0, 0x91c6570}, {0xc020506f00, 0x0, 0x200?})
/home/prow/go/src/k8s.io/kubernetes/staging/src/k8s.io/apimachinery/pkg/util/runtime/runtime.go:107 +0x116
k8s.io/apimachinery/pkg/util/runtime.HandleCrash({0x0, 0x0, 0xc00685ddc0?})
/home/prow/go/src/k8s.io/kubernetes/staging/src/k8s.io/apimachinery/pkg/util/runtime/runtime.go:64 +0x17b
panic({0x59381a0?, 0x91c6570?})
/usr/local/go/src/runtime/panic.go:783 +0x132
k8s.io/kubernetes/pkg/scheduler/framework/plugins/dynamicresources.(*DynamicResources).bindClaim.func2()
/home/prow/go/src/k8s.io/kubernetes/pkg/scheduler/framework/plugins/dynamicresources/dynamicresources.go:1247 +0x730
k8s.io/client-go/util/retry.OnError.func1()
/home/prow/go/src/k8s.io/kubernetes/staging/src/k8s.io/client-go/util/retry/util.go:51 +0x30
k8s.io/apimachinery/pkg/util/wait.runConditionWithCrashProtection(0x9ebcca?)
/home/prow/go/src/k8s.io/kubernetes/staging/src/k8s.io/apimachinery/pkg/util/wait/wait.go:150 +0x3e
k8s.io/apimachinery/pkg/util/wait.ExponentialBackoff({0x989680, 0x3ff0000000000000, 0x3fb999999999999a, 0x2, 0x0}, 0xc020507410)
/home/prow/go/src/k8s.io/kubernetes/staging/src/k8s.io/apimachinery/pkg/util/wait/backoff.go:477 +0x5a
k8s.io/client-go/util/retry.OnError({0x989680, 0x3ff0000000000000, 0x3fb999999999999a, 0x5, 0x0}, 0xc02c2d5380?, 0x4?)
/home/prow/go/src/k8s.io/kubernetes/staging/src/k8s.io/client-go/util/retry/util.go:50 +0x96
k8s.io/client-go/util/retry.RetryOnConflict(...)
/home/prow/go/src/k8s.io/kubernetes/staging/src/k8s.io/client-go/util/retry/util.go:104
k8s.io/kubernetes/pkg/scheduler/framework/plugins/dynamicresources.(*DynamicResources).bindClaim(0xc0024adb20, {0x69cea28, 0xc0061acbe0}, 0xc011876800, 0x0, 0xc025163408, {0xc021909d80, 0x8})
/home/prow/go/src/k8s.io/kubernetes/pkg/scheduler/framework/plugins/dynamicresources/dynamicresources.go:1207 +0x845
k8s.io/kubernetes/pkg/scheduler/framework/plugins/dynamicresources.(*DynamicResources).PreBind-range1(...)
/home/prow/go/src/k8s.io/kubernetes/pkg/scheduler/framework/plugins/dynamicresources/dynamicresources.go:1073
k8s.io/kubernetes/pkg/scheduler/framework/plugins/dynamicresources.(*DynamicResources).PreBind.(*claimStore).all.func2(...)
/home/prow/go/src/k8s.io/kubernetes/pkg/scheduler/framework/plugins/dynamicresources/claims.go:72
k8s.io/kubernetes/pkg/scheduler/framework/plugins/dynamicresources.(*DynamicResources).PreBind(0xc0024adb20, {0x69cea28, 0xc0061acbe0}, {0x69fc840?, 0xc0286f2540?}, 0xc025163408, {0xc021909d80, 0x8})
/home/prow/go/src/k8s.io/kubernetes/pkg/scheduler/framework/plugins/dynamicresources/dynamicresources.go:1071 +0x246
k8s.io/kubernetes/pkg/scheduler/framework/runtime.(*frameworkImpl).runPreBindPlugin(0xc009628dc8, {0x69cea28, 0xc0061acbe0}, {0x7eabfddddb30, 0xc0024adb20}, {0x69fc840, 0xc0286f2540}, 0xc025163408, {0xc021909d80, 0x8})
/home/prow/go/src/k8s.io/kubernetes/pkg/scheduler/framework/runtime/framework.go:1532 +0x2e2
k8s.io/kubernetes/pkg/scheduler/framework/runtime.(*frameworkImpl).RunPreBindPlugins.func2({0x7eabfddddb30, 0xc0024adb20})
/home/prow/go/src/k8s.io/kubernetes/pkg/scheduler/framework/runtime/framework.go:1461 +0x1cf
k8s.io/kubernetes/pkg/scheduler/framework/runtime.(*frameworkImpl).RunPreBindPlugins(0xc009628dc8, {0x69cea28, 0xc0061ac690}, {0x69fc840, 0xc0286f2540}, 0xc025163408, {0xc021909d80, 0x8})
/home/prow/go/src/k8s.io/kubernetes/pkg/scheduler/framework/runtime/framework.go:1484 +0x623
k8s.io/kubernetes/pkg/scheduler.(*Scheduler).bindingCycle(0xc02a6a7500, {0x69cea28, 0xc00f22a690}, {0x69fc840, 0xc0286f2540}, {0x6a32e60, 0xc009628dc8}, {{0xc021909d80, 0x8}, 0x8, ...}, ...)
/home/prow/go/src/k8s.io/kubernetes/pkg/scheduler/schedule_one.go:457 +0x72a
k8s.io/kubernetes/pkg/scheduler.(*Scheduler).runBindingCycle(0xc02a6a7500, {0x69ce9f0?, 0xc0027e5470?}, {0x69fc840, 0xc0286f2540}, {0x6a32e60, 0xc009628dc8}, {{0xc021909d80, 0x8}, 0x8, ...}, ...)
/home/prow/go/src/k8s.io/kubernetes/pkg/scheduler/schedule_one.go:164 +0x1e8
Kubernetes (K8s)
Kubernetes, also known as K8s, is an open source system for managing containerized applications across multiple hosts. It provides basic mechanisms for the 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.
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.
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 the 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.