Update statefulset concepts doc to use apps/v1beta2 APIs #5420
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| @@ -100,10 +100,40 @@ spec: | |||
| resources: | |||
| requests: | |||
| storage: 1Gi | |||
| --- | |||
| kind: PersistentVolume | |||
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Another way is to use StorageClass, but i am not sure whether it will be too advanced for concepts tutorial.
- reduce number of replicas from 3 to 2 so that the YAML file will not be too long
- explicitly add the 2 PVs to ensure all pods are running
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If we remove the PVs, a user who is new to statefulset may not know that there is a need to create the PVs too. The pods will be pending forever if the PVs are not created.
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As discussed by person, the PVs can be removed. The concepts tutorials are not meant to have the YAML file cut and pasted. The statefulset should create the PVs automatically when dynamic provisioner is available.
kow3ns
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Sep 13, 2017
| @@ -11,9 +11,7 @@ title: StatefulSets | |||
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| {% capture overview %} | |||
| **StatefulSets are a beta feature in 1.7. This feature replaces the | |||
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I would remove the reference to PetSets at this point. It is not possible to upgrade to 1.8 without going through 1.7 and we have a reference to it in those docs. Perhaps
"StatefulSet is the workload API object used to manage stateful applications. StatefulSets are beta in 1.8."
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Sure, I will remove all references to PetSets.
| @@ -100,10 +100,40 @@ spec: | |||
| resources: | |||
| requests: | |||
| storage: 1Gi | |||
| --- | |||
| kind: PersistentVolume | |||
| ``` | ||
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| ## Pod Identity | ||
| StatefulSet Pods have a unique identity that is comprised of an ordinal, a | ||
| StatefulSet Pods have a unique identity that comprises of an ordinal, a |
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revert, the previous is grammatically correct, this is not
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I will revert the change.
Nit: According to dictionary, the use of of after the word comprise should be avoided. It should be either is comprised of or comprises, but not comprises of.
| @@ -222,6 +252,15 @@ updates to its `.spec.template` will not be propagated to its Pods. | |||
| In most cases you will not need to use a partition, but they are useful if you want to stage an | |||
| update, roll out a canary, or perform a phased roll out. | |||
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| ## Selectors and Labels | |||
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Remove this section ... StatefulSet selector was never mutable.
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Sorry - I am aware that there was no change to statefulset update strategy (in my previous PR), but didn't know that statefulset selector was never mutable.
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| In Kubernetes 1.8 and later, selector of a StatefulSet is made immutable after creation. The `.spec.selector.matchLabels` field must match `.spec.template.metadata.labels` field during creation of the StatefulSet, and cannot be changed during future updates. As the selector is now immutable, a nil `.spec.selector.matchLabels` field will not be defaulted to a non-nil `.spec.template.metadata.labels` value during creation. Instead, this is considered as user error because both fields do not match. In addition, `.metadata.labels` field will also not be defaulted to match the `.spec.template.metadata.labels` field. The user has to explicitly set the `.metadata.labels` field, but it can be different from `.spec.template.metadata.labels` value. | ||
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| ### Overlapping Selectors |
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Remove this, overlapping selectors is not an issue with Statefulset because of the naming.
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Noted - thanks for pointing it out.
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| ### Overlapping Selectors | ||
| It is possible for a pod to be created with labels matching selectors of multiple StatefulSets (or multiple controllers of different types such as both StatefulSet and ReplicaSet). Although k8s allows overlapping selectors to exist, they result in undefined behaviors. This is considered as user error, in which the user needs to manage deletion of the pod manually. | ||
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Add an indication that in 1.8 the selector will no longer be defaulted.
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Sep 13, 2017
| @@ -222,6 +220,12 @@ updates to its `.spec.template` will not be propagated to its Pods. | |||
| In most cases you will not need to use a partition, but they are useful if you want to stage an | |||
| update, roll out a canary, or perform a phased roll out. | |||
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| ## Selectors | |||
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| Same as other controllers, the StatefulSet utilizes selectors to identify pods that it should manage. For a pod to be managed by a StatefulSet, the pod needs to have labels matching the StatefulSet's selectors. However, the StatefulSet does not keep track whether a pod is created by it or another controller. The pods will persist when the StatefulSet is deleted (except when the user performs a [cascading deletion](https://kubernetes.io/docs/concepts/workloads/controllers/garbage-collection/)). | |||
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@kow3ns IMO, it may be better to discuss what a selector is before moving on to indicate that there is no more selector defaulting in next paragraph.
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Label selectors are explained elsewhere in the documentation. We don't need to be repetitive. You can link to the Label selector documentation without reiterating the information there.
This paragraph is also not correct. StatefulSet uses a combination of label selectors, controller references, and pod names to determine which Pods it should manage.
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Sure, i will put a link there instead of explaining about the label selectors.
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@steveperry-53 If everything looks good to you, do you mind to provide |
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Sep 15, 2017
| @@ -222,6 +222,10 @@ updates to its `.spec.template` will not be propagated to its Pods. | |||
| In most cases you will not need to use a partition, but they are useful if you want to stage an | |||
| update, roll out a canary, or perform a phased roll out. | |||
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| ## Selectors | |||
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| The StatefulSet uses a combination of [label selectors](/docs/user-guide/labels/#label-selectors), controller references, and pod names to determine which pods it should manage. In Kubernetes 1.8 and later, there will be no selector defaulting. `.spec.selector` field will not be defaulted to match `.spec.template.metadata.labels` field during StatefulSet creation. The user has to explicitly set the selectors to match the template labels. | |||
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Suggest the following
Pod Selector
You must set the spec.selector field of a StatefulSet to match the labels of its .spec.template.metadata.labels. Prior to Kubernetes 1.8, the spec.selector field was defaulted when omitted. In 1.8 and later versions, failing to specify a matching Pod Selector will result in a validation error during StatefulSet creation.
Also move this section to be above Pod Identity. The change should be made prevalent.
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@kow3ns Incorporated your suggestion. |
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/lgtm |
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Sep 29, 2017
* GC now supports non-core resources * Add two examples about how to analysis audits of kube-apiserver (#4264) * Deprecate system:nodes binding * [1.8] StatefulSet `initialized` annotation is now ignored. * inits the kubeadm upgrade docs addresses /issues/4689 * adds kubeadm upgrade cmd to ToC addresses /issues/4689 * add workload placement docs * ScaleIO - document udpate for 1.8 * Add documentation on storageClass.mountOptions and PV.mountOptions (#5254) * Add documentation on storageClass.mountOptions and PV.mountOptions * convert notes into callouts * Add docs for CustomResource validation add info about supported fields * advanced audit beta features (#5300) * Update job workload doc with backoff failure policy (#5319) Add to the Jobs documentation how to use the new backoffLimit field that limit the number of Pod failure before considering the Job as failed. * Documented additional AWS Service annotations (#4864) * Add device plugin doc under concepts/cluster-administration. (#5261) * Add device plugin doc under concepts/cluster-administration. * Update device-plugins.md * Update device-plugins.md Add meta description. Fix typo. Change bare metal deployment to manual deployment. * Update device-plugins.md Fix typo again. * Update page.version. (#5341) * Add documentation on storageClass.reclaimPolicy (#5171) * [Advanced audit] use new herf for audit-api (#5349) This tag contains all the changes in v1beta1 version. Update it now. * Added documentation around creating the InitializerConfiguration for the persistent volume label controller in the cloud-controller-manager (#5255) * Documentation for kubectl plugins (#5294) * Documentation for kubectl plugins * Update kubectl-plugins.md * Update kubectl-plugins.md * Updated CPU manager docs to match implementation. (#5332) * Noted limitation of alpha static cpumanager. * Updated CPU manager docs to match implementation. - Removed references to CPU pressure node condition and evictions. - Added note about new --cpu-manager-reconcile-period flag. - Added note about node allocatable requirements for static policy. - Noted limitation of alpha static cpumanager. * Move cpu-manager task link to rsc mgmt section. * init containers annotation removed in 1.8 (#5390) * Add documentation for TaintNodesByCondition (#5352) * Add documentation for TaintNodesByCondition * Update nodes.md * Update taint-and-toleration.md * Update daemonset.md * Update nodes.md * Update taint-and-toleration.md * Update daemonset.md * Fix deployments (#5421) * Document extended resources and OIR deprecation. (#5399) * Document extended resources and OIR deprecation. * Updated extended resources doc per reviews. * reverts extra spacing in _data/tasks.yml * addresses `kubeadm upgrade` review comments Feedback from @chenopis, @luxas, and @steveperry-53 addressed with this commit * HugePages documentation (#5419) * Update cpu-management-policies.md (#5407) Fixed the bad link. Modified "cpu" to "CPU". Added more 'yaml' as supplement. * Update RBAC docs for v1 (#5445) * Add user docs for pod priority and preemption (#5328) * Add user docs for pod priority and preemption * Update pod-priority-preemption.md * More updates * Update docs/admin/kubeadm.md for 1.8 (#5440) - Made a couple of minor wording changes (not strictly 1.8 related). - Did some reformatting (not strictly 1.8 related). - Updated references to the default token TTL (was infinite, now 24 hours). - Documented the new `--discovery-token-ca-cert-hash` and `--discovery-token-unsafe-skip-ca-verification` flags for `kubeadm join`. - Added references to the new `--discovery-token-ca-cert-hash` flag in all the default examples. - Added a new _Security model_ section that describes the security tradeoffs of the various discovery modes. - Documented the new `--groups` flag for `kubeadm token create`. - Added a note of caution under _Automating kubeadm_ that references the _Security model_ section. - Updated the component version table to drop 1.6 and add 1.8. - Update `_data/reference.yml` to try to get the sidebar fixed up and more consistent with `kubefed`. * Update StatefulSet Basics for 1.8 release (#5398) * addresses `kubeadm upgrade` review comments 2nd iteration review comments by @luxas * adds kubelet upgrade section to kubeadm upgrade * Fix a bulleted list on docs/admin/kubeadm.md. (#5458) I updated this doc yesterday and I was absolutely sure I fixed this, but I just saw that this commit got lost somehow. This was introduced recently in #5440. * Clarify the API to check for device plugins * Moving Flexvolume to separate out-of-tree section * addresses `kubeadm upgrade` review comments CC: @luxas * fixes kubeadm upgrade index * Update Stackdriver Logging documentation (#5495) * Re-update WordPress and MySQL PV doc to use apps/v1beta2 APIs (#5526) * Update statefulset concepts doc to use apps/v1beta2 APIs (#5420) * add document on kubectl's behavior regarding initializers (#5505) * Update docs/admin/kubeadm.md to cover self-hosting in 1.8. (#5497) This is a new beta feature in 1.8. * Update kubectl patch doc to use apps/v1beta2 APIs (#5422) * [1.8] Update "Run Applications" tasks to apps/v1beta2. (#5525) * Update replicated stateful application task for 1.8. * Update single instance stateful app task for 1.8. * Update stateless app task for 1.8. * Update kubectl patch task for 1.8. * fix the link of persistent storage (#5515) * update the admission-controllers.md index.md what-is-kubernetes.md link * fix the link of persistent storage * Add quota support for local ephemeral storage (#5493) * Add quota support for local ephemeral storage update the doc to this alpha feature * Update resource-quotas.md * Updated Deployments concepts doc (#5491) * Updated Deployments concepts doc * Addressed comments * Addressed more comments * Modify allocatable storage to ephemeral-storage (#5490) Update the doc to use ephemeral-storage instead of storage * Revamped concepts doc for ReplicaSet (#5463) * Revamped concepts doc for ReplicaSet * Minor changes to call out specific versions for selector defaulting and immutability * Addressed doc review comments * Remove petset documentations (#5395) * Update docs to use batch/v1beta1 cronjobs (#5475) * add federation job doc (#5485) * add federation job doc * Update job.md Edits for clarity and consistency * Update job.md Fixed a typo * update DaemonSet concept for 1.8 release (#5397) * update DaemonSet concept for 1.8 release * Update daemonset.md Fix typo. than -> then * Update bootstrap tokens doc for 1.8. (#5479) * Update bootstrap tokens doc for 1.8. This has some changes I missed when I was updating the main kubeadm documention: - Bootstrap tokens are now beta, not alpha (kubernetes/enhancements#130) - The apiserver flag to enable the authenticator changedin 1.8 (kubernetes/kubernetes#51198) - Added `auth-extra-groups` documentaion (kubernetes/kubernetes#50933) - Updated the _Token Management with `kubeadm`_ section to link to the main kubeadm docs, since it was just duplicated information. * Update bootstrap-tokens.md * Updated the Cassandra tutorial to use apps/v1beta2 (#5548) * add docs for AllowPrivilegeEscalation (#5448) Signed-off-by: Jess Frazelle <[email protected]> * Add local ephemeral storage alpha feature in managing compute resource (#5522) * Add local ephemeral storage alpha feature in managing compute resource Since 1.8, we add the local ephemeral storage alpha feature as one resource type to manage. Add this feature into the doc. * Update manage-compute-resources-container.md * Update manage-compute-resources-container.md * Update manage-compute-resources-container.md * Update manage-compute-resources-container.md * Update manage-compute-resources-container.md * Update manage-compute-resources-container.md * Added documentation for Metrics Server (#5560) * authorization: improve authorization debugging docs (#5549) * Document mount propagation (#5544) * Update /docs/setup/independent/create-cluster-kubeadm.md for 1.8. (#5524) This introduction needed a couple of small tweaks to cover the `--discovery-token-ca-cert-hash` flag added in kubernetes/kubernetes#49520 and some version bumps. * Add task doc for alpha dynamic kubelet configuration (#5523) * Fix input/output of selfsubjectaccess review (#5593) * Add docs for implementing resize (#5528) * Add docs for implementing resize * Update admission-controllers.md * Added link to PVC section * minor typo fixes * Update NetworkPolicy concept guide with egress and CIDR changes (#5529) * update zookeeper tutorial for 1.8 release * add doc for hostpath type (#5503) * Federated Hpa feature doc (#5487) * Federated Hpa feature doc * Federated Hpa feature doc review fixes * Update hpa.md * Update hpa.md * update cloud controller manager docs for v1.8 * Update cronjob with defaults information (#5556) * Kubernetes 1.8 reference docs (#5632) * Kubernetes 1.8 reference docs * Kubectl reference docs for 1.8 * Update side bar with 1.8 kubectl and api ref docs links * remove petset.md * update on state of HostAlias in 1.8 with hostNetwork Pod support (#5644) * Fix cron job deletion section (#5655) * update imported docs (#5656) * Add documentation for certificate rotation. (#5639) * Link to using kubeadm page * fix the command output fix the command output * fix typo in api/resources reference: "Worloads" * Add documentation for certificate rotation. * Create TOC entry for cloud controller manager. (#5662) * Updates for new versions of API types * Followup 5655: fix link to garbage collection (#5666) * Temporarily redirect resources-reference to api-reference. (#5668) * Update config for 1.8 release. (#5661) * Update config for 1.8 release. * Address reviewer comments. * Switch references in HPA docs from alpha to beta (#5671) The HPA docs still referenced the alpha version. This switches them to talk about v2beta1, which is the appropriate version for Kubernetes 1.8 * Deprecate openstack heat (#5670) * Fix typo in pod preset conflict example Move container port definition to the correct line. * Highlight openstack-heat provider deprecation The openstack-heat provider for kube-up is being deprecated and will be removed in a future release. * Temporarily fix broken links by redirecting. (#5672) * Fix broken links. (#5675) * Fix render of code block (#5674) * Fix broken links. (#5677) * Add a small note about auto-bootstrapped CSR ClusterRoles (#5660) * Update kubeadm install doc for v1.8 (#5676) * add draft workloads api content for 1.8 (#5650) * add draft workloads api content for 1.8 * edits per review, add tables, for 1.8 workloads api doc * fix typo * Minor fixes to kubeadm 1.8 upgrade guide. (#5678) - The kubelet upgrade instructions should be done on every host, not just worker nodes. - We should just upgrade all packages, instead of calling out kubelet specifically. This will also upgrade kubectl, kubeadm, and kubernetes-cni, if installed. - Draining nodes should also ignore daemonsets, and master errors can be ignored. - Make sure that the new kubeadm download is chmoded correctly. - Add a step to run `kubeadm version` to verify after downloading. - Manually approve new kubelet CSRs if rotation is enabled (known issue). * Release 1.8 (#5680) * Fix versions for 1.8 API ref docs * Updates for 1.8 kubectl reference docs * Kubeadm /docs/admin/kubeadm.md cleanup, editing. (#5681) * Update docs/admin/kubeadm.md (mostly 1.8 related). This is Fabrizio's work, which I'm committing along with my edits (in a commit on top of this). * A few of my own edits to clarify and clean up some Markdown.
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This PR updates YAML file of StatefulSet concepts doc to use apps/v1beta2 APIs, and adds a section about selector immutability and defaulting removal for
.spec.selectorand.spec.template.labels.This change is