Automatic merge from submit-queue
kubeadm: Enable the Node Authorizer/Admission plugin in v1.7
**What this PR does / why we need it**:
This is similar to https://github.com/kubernetes/kubernetes/pull/46796, but for kubeadm.
Basically it was a part of https://github.com/kubernetes/kubernetes/pull/46796, but there were some other upgradability and compability concerns for kubeadm I took care of while working today.
Example:
```console
$ kubeadm init --kubernetes-version v1.7.0-beta.0
[kubeadm] WARNING: kubeadm is in beta, please do not use it for production clusters.
[init] Using Kubernetes version: v1.7.0-beta.0
[init] Using Authorization mode: [RBAC Node]
...
$ sudo kubectl --kubeconfig=/etc/kubernetes/kubelet.conf get secret foo
Error from server (Forbidden): User "system:node:thegopher" cannot get secrets in the namespace "default".: "no path found to object" (get secrets foo)
$ echo '{"apiVersion":"v1","kind":"Node","metadata":{"name":"foo"}}' | sudo kubectl create -f - --kubeconfig=/etc/kubernetes/kubelet.conf
Error from server (Forbidden): error when creating "STDIN": nodes "foo" is forbidden: node thegopher cannot modify node foo
```
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
Depends on https://github.com/kubernetes/kubernetes/pull/46864 (uses that PR as a base, will rebase once it's merged)
Please only review the second commit. Will also fix tests in a minute.
**Release note**:
```release-note
kubeadm: Enable the Node Authorizer/Admission plugin in v1.7
```
@mikedanese @liggitt @pipejakob @roberthbailey @jbeda @timothysc
Automatic merge from submit-queue (batch tested with PRs 47024, 47050, 47086, 47081, 47013)
kubeadm: Make the creation of the RBAC rules phase idempotent
**What this PR does / why we need it**:
Bugfix: Currently kubeadm fails with a non-zero code if resources it's trying to create already exist. This PR fixes that by making kubeadm try to Update resources that already exist.
After this PR, https://github.com/kubernetes/kubernetes/pull/46879 and a beta.1 release, kubeadm will be fully upgradeable from v1.6 to v1.7 using only kubeadm init.
Last piece of https://github.com/kubernetes/kubeadm/issues/288
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
Fixes: https://github.com/kubernetes/kubeadm/issues/288
**Special notes for your reviewer**:
**Release note**:
```release-note
kubeadm: Modifications to cluster-internal resources installed by kubeadm will be overwritten when upgrading from v1.6 to v1.7.
```
@pipejakob @mikedanese @timothysc
Automatic merge from submit-queue (batch tested with PRs 43005, 46660, 46385, 46991, 47103)
Consolidate sysctl commands for kubelet
**What this PR does / why we need it**:
These commands are important enough to be in the Kubelet itself.
By default, Ubuntu 14.04 and Debian Jessie have these set to 200 and
20000. Without this setting, nodes are limited in the number of
containers that they can start.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes#26005
**Special notes for your reviewer**:
I had a difficult time writing tests for this. It is trivial to create a fake sysctl for testing, but the Kubelet does not have any tests for the prior settings.
**Release note**:
```release-note
```
Automatic merge from submit-queue (batch tested with PRs 46235, 44786, 46833, 46756, 46669)
implements StatefulSet update
**What this PR does / why we need it**:
1. Implements rolling update for StatefulSets
2. Implements controller history for StatefulSets.
3. Makes StatefulSet status reporting consistent with DaemonSet and ReplicaSet.
https://github.com/kubernetes/features/issues/188
**Special notes for your reviewer**:
**Release note**:
```release-note
Implements rolling update for StatefulSets. Updates can be performed using the RollingUpdate, Paritioned, or OnDelete strategies. OnDelete implements the manual behavior from 1.6. status now tracks
replicas, readyReplicas, currentReplicas, and updatedReplicas. The semantics of replicas is now consistent with DaemonSet and ReplicaSet, and readyReplicas has the semantics that replicas did prior to this release.
```
Automatic merge from submit-queue
kubeadm: improve quickstart instructions
**What this PR does / why we need it**:
Improves instructional output following setup of a kubernetes master with kubeadm.
This helps prevent unnecessary support overhead such as: https://github.com/kubernetes/kubeadm/issues/212#issuecomment-292015402
**Example current output**:
```
To start using your cluster, you need to run (as a regular user):
sudo cp /etc/kubernetes/admin.conf $HOME/
sudo chown $(id -u):$(id -g) $HOME/admin.conf
export KUBECONFIG=$HOME/admin.conf
```
**Example new output**:
```
To start using your cluster, you need to run (as a regular user):
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
```
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 46718, 46828, 46988)
Simply changed the names of packages of some admission plugins.
**What this PR does / why we need it**:
This PR simply changes the names of packages of some admission plugins so that they are not in conflict with admission pkg.
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 46718, 46828, 46988)
Update docs/ links to point to main site
**What this PR does / why we need it**:
This updates various links to either point to kubernetes.io or to the kubernetes/community repo instead of the legacy docs/ tree in k/k
Pre-requisite for #46813
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
@kubernetes/sig-docs-maintainers @chenopis @ahmetb @thockin
Automatic merge from submit-queue
Rename {kube- ->}apiextensions-{-> api}server
Completely mechanical renaming, as preparation of the repo sync. This repo is generic, the prefix does not make sense.
Part of issue https://github.com/kubernetes/kubernetes/issues/46702
TODOs
- [ ] Waiting for the submit queue to settle, then rebase.
Automatic merge from submit-queue (batch tested with PRs 46897, 46899, 46864, 46854, 46875)
kubeadm: Idempotent service account creation.
**What this PR does / why we need it**:
During `kubeadm init`, ignore errors for duplicates when creating service accounts.
https://github.com/kubernetes/kubeadm/issues/278
Fixes: https://github.com/kubernetes/kubeadm/issues/288
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 46897, 46899, 46864, 46854, 46875)
kubeadm: Make kubeadm use the right CSR approver for the right version
**What this PR does / why we need it**:
fixes regression caused in: https://github.com/kubernetes/kubernetes/pull/45619
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
Fixes: https://github.com/kubernetes/kubeadm/issues/289
**Special notes for your reviewer**:
cc @pipejakob our e2e CI should probably go green after this change
**Release note**:
```release-note
NONE
```
@mikedanese @pipejakob @timothysc @liggitt
Automatic merge from submit-queue (batch tested with PRs 46787, 46876, 46621, 46907, 46819)
kubeadm: Only create bootstrap configmap if not exists.
**What this PR does / why we need it**:
The fact that this method was not idempotent was breaking kubeadm upgrades.
https://github.com/kubernetes/kubeadm/issues/278
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue
kubeadm: don't duplicate master taint if it already exists.
**What this PR does / why we need it**:
This helps enable a graceful upgrade/downgrade process between 1.6.x and 1.7.x kubeadm clusters (although no guarantees outside of that range) by doing:
$ kubeadm init --kubernetes-version <version> --skip-preflight-checks
Without this change, the command fails with an error that the node taint is duplicated.
This is part of https://github.com/kubernetes/kubeadm/issues/278
**Release note**:
```release-note
NONE
```
Fixes: https://github.com/kubernetes/kubeadm/issues/288
Automatic merge from submit-queue (batch tested with PRs 46967, 46992, 43338, 46717, 46672)
Generate protobuf for the audit API
Add protobuf generation & annotations for the advanced auditing API. We're not using them directly now, but settling on the field numbering will help with some 3rd party integrations.
For kubernetes/features#22
/cc @ihmccreery
Automatic merge from submit-queue (batch tested with PRs 44883, 46836, 46765, 46683, 46050)
While deleting a namespace, the TPR instances under this ns should be…
… deleted.
While deleting a namespace, the TPR instances under this ns should be deleted.
Fixed#46736
**Release note**:
```
None
```
Automatic merge from submit-queue (batch tested with PRs 46972, 42829, 46799, 46802, 46844)
promote tls-bootstrap to beta
last commit of this PR.
Towards https://github.com/kubernetes/kubernetes/issues/46999
```release-note
Promote kubelet tls bootstrap to beta. Add a non-experimental flag to use it and deprecate the old flag.
```
Automatic merge from submit-queue (batch tested with PRs 46550, 46663, 46816, 46820, 46460)
Add configuration for encryption providers
## Additions
Allows providing a configuration file (using flag `--experimental-encryption-provider-config`) to use the existing AEAD transformer (with multiple keys) by composing mutable transformer, prefix transformer (for parsing providerId), another prefix transformer (for parsing keyId), and AES-GCM transformers (one for each key). Multiple providers can be configured using the configuration file.
Example configuration:
```
kind: EncryptionConfig
apiVersion: v1
resources:
- resources:
- namespaces
providers:
- aes:
keys:
- name: key1
secret: c2vjcmv0iglzihnly3vyzq==
- name: key2
secret: dghpcybpcybwyxnzd29yza==
- identity: {}
```
Need for configuration discussed in:
#41939
[Encryption](3418b4e4c6/contributors/design-proposals/encryption.md)
**Pathway of a read/write request**:
1. MutableTransformer
2. PrefixTransformer reads the provider-id, and passes the request further if that matches.
3. PrefixTransformer reads the key-id, and passes the request further if that matches.
4. GCMTransformer tries decrypting and authenticating the cipher text in case of reads. Similarly for writes.
## Caveats
1. To keep the command line parameter parsing independent of the individual transformer's configuration, we need to convert the configuration to an `interface{}` and manually parse it in the transformer. Suggestions on better ways to do this are welcome.
2. Flags `--encryption-provider` and `--encrypt-resource` (both mentioned in [this document](3418b4e4c6/contributors/design-proposals/encryption.md) ) are not supported in this because they do not allow more than one provider, and the current format for the configuration file possibly supersedes their functionality.
3. Currently, it can be tested by adding `--experimental-encryption-provider-config=config.yml` to `hack/local-up-cluster.sh` on line 511, and placing the above configuration in `config.yml` in the root project directory.
Previous discussion on these changes:
https://github.com/sakshamsharma/kubernetes/pull/1
@jcbsmpsn @destijl @smarterclayton
## TODO
1. Investigate if we need to store keys on disk (per [encryption.md](3418b4e4c6/contributors/design-proposals/encryption.md (option-1-simple-list-of-keys-on-disk)))
2. Look at [alpha flag conventions](https://github.com/kubernetes/kubernetes/blob/master/pkg/features/kube_features.go)
3. Need to reserve `k8s:enc` prefix formally for encrypted data. Else find a better way to detect transformed data.
Handle failure cases on startup gracefully to avoid causing cascading
errors and poor initialization in other components. Initial errors from
config load cause the initializer to pause and hold requests. Return
typed errors to better communicate failures to clients.
Add code to handle two specific cases - admin wants to bypass
initialization defaulting, and mirror pods (which want to bypass
initialization because the kubelet owns their lifecycle).
This helps enable a graceful upgrade/downgrade process between 1.6.x and
1.7.x kubeadm clusters (although no guarantees outside of that range) by
doing:
$ kubeadm init --kubernetes-version <version> --skip-preflight-checks
Without this change, the command fails with an error that the node taint
is duplicated.
This is part of https://github.com/kubernetes/kubeadm/issues/278
Automatic merge from submit-queue (batch tested with PRs 46681, 46786, 46264, 46680, 46805)
Enable Dialer on the Aggregator
Centralize the creation of the dialer during startup.
Have the dialer then passed in to both APIServer and Aggregator.
Aggregator the uses the dialer as its Transport base.
**What this PR does / why we need it**:Enables the Aggregator to use the Dialer/SSHTunneler to connect to the user-apiserver.
**Which issue this PR fixes** : fixes ##46679
**Special notes for your reviewer**:
**Release note**: None
Automatic merge from submit-queue (batch tested with PRs 40760, 46706, 46783, 46742, 46751)
complete the controller context for init funcs
This completes the conversion to initFuncs for the controller initialization to make easier and more manageable to add them.
Automatic merge from submit-queue
Implement Daemonset history
~Depends on #45867 (the 1st commit, ignore it when reviewing)~ (already merged)
Ref https://github.com/kubernetes/community/pull/527/ and https://github.com/kubernetes/community/pull/594
@kubernetes/sig-apps-api-reviews @kubernetes/sig-apps-pr-reviews @erictune @kow3ns @lukaszo @kargakis
---
TODOs:
- [x] API changes
- [x] (maybe) Remove rollback subresource if we decide to do client-side rollback
- [x] deployment controller
- [x] controller revision
- [x] owner ref (claim & adoption)
- [x] history reconstruct (put revision number, hash collision avoidance)
- [x] de-dup history and relabel pods
- [x] compare ds template with history
- [x] hash labels (put it in controller revision, pods, and maybe deployment)
- [x] clean up old history
- [x] Rename status.uniquifier when we reach consensus in #44774
- [x] e2e tests
- [x] unit tests
- [x] daemoncontroller_test.go
- [x] update_test.go
- [x] ~(maybe) storage_test.go // if we do server side rollback~
kubectl part is in #46144
---
**Release note**:
```release-note
```
Automatic merge from submit-queue (batch tested with PRs 36721, 46483, 45500, 46724, 46036)
stop special casing the loopback connection for aggregator
Fixes a TODO for the aggregator loopback connection.
Automatic merge from submit-queue
Add initializer support to admission and uninitialized filtering to rest storage
Initializers are the opposite of finalizers - they allow API clients to react to object creation and populate fields prior to other clients seeing them.
High level description:
1. Add `metadata.initializers` field to all objects
2. By default, filter objects with > 0 initializers from LIST and WATCH to preserve legacy client behavior (known as partially-initialized objects)
3. Add an admission controller that populates .initializer values per type, and denies mutation of initializers except by certain privilege levels (you must have the `initialize` verb on a resource)
4. Allow partially-initialized objects to be viewed via LIST and WATCH for initializer types
5. When creating objects, the object is "held" by the server until the initializers list is empty
6. Allow some creators to bypass initialization (set initializers to `[]`), or to have the result returned immediately when the object is created.
The code here should be backwards compatible for all clients because they do not see partially initialized objects unless they GET the resource directly. The watch cache makes checking for partially initialized objects cheap. Some reflectors may need to change to ask for partially-initialized objects.
```release-note
Kubernetes resources, when the `Initializers` admission controller is enabled, can be initialized (defaulting or other additive functions) by other agents in the system prior to those resources being visible to other clients. An initialized resource is not visible to clients unless they request (for get, list, or watch) to see uninitialized resources with the `?includeUninitialized=true` query parameter. Once the initializers have completed the resource is then visible. Clients must have the the ability to perform the `initialize` action on a resource in order to modify it prior to initialization being completed.
```
1. Create controllerrevisions (history) and label pods with template
hash for both RollingUpdate and OnDelete update strategy
2. Clean up old, non-live history based on revisionHistoryLimit
3. Remove duplicate controllerrevisions (the ones with the same template)
and relabel their pods
4. Update RBAC to allow DaemonSet controller to manage
controllerrevisions
5. In DaemonSet controller unit tests, create new pods with hash labels
Automatic merge from submit-queue
Add local storage (scratch space) allocatable support
This PR adds the support for allocatable local storage (scratch space).
This feature is only for root file system which is shared by kubernetes
componenets, users' containers and/or images. User could use
--kube-reserved flag to reserve the storage for kube system components.
If the allocatable storage for user's pods is used up, some pods will be
evicted to free the storage resource.
This feature is part of local storage capacity isolation and described in the proposal https://github.com/kubernetes/community/pull/306
**Release note**:
```release-note
This feature exposes local storage capacity for the primary partitions, and supports & enforces storage reservation in Node Allocatable
```
Automatic merge from submit-queue (batch tested with PRs 46239, 46627, 46346, 46388, 46524)
Dynamic webhook admission control plugin
Unit tests pass.
Needs plumbing:
* [ ] service resolver (depends on @wfender PR)
* [x] client cert (depends on ????)
* [ ] hook source (depends on @caesarxuchao PR)
Also at least one thing will need to be renamed after Chao's PR merges.
```release-note
Allow remote admission controllers to be dynamically added and removed by administrators. External admission controllers make an HTTP POST containing details of the requested action which the service can approve or reject.
```
Automatic merge from submit-queue (batch tested with PRs 46239, 46627, 46346, 46388, 46524)
move labels to components which own the APIs
During the apimachinery split in 1.6, we accidentally moved several label APIs into apimachinery. They don't belong there, since the individual APIs are not general machinery concerns, but instead are the concern of particular components: most commonly the kubelet. This pull moves the labels into their owning components and out of API machinery.
@kubernetes/sig-api-machinery-misc @kubernetes/api-reviewers @kubernetes/api-approvers
@derekwaynecarr since most of these are related to the kubelet
Automatic merge from submit-queue (batch tested with PRs 46726, 41912, 46695, 46034, 46551)
Rotate kubelet client certificate.
Changes the kubelet so it bootstraps off the cert/key specified in the
config file and uses those to request new cert/key pairs from the
Certificate Signing Request API, as well as rotating client certificates
when they approach expiration.
Default behavior is for client certificate rotation to be disabled. If enabled
using a command line flag, the kubelet exits each time the certificate is
rotated. I tried to use `GetCertificate` in [tls.Config](https://golang.org/pkg/crypto/tls/#Config) but it is only called
on the server side of connections. Then I tried `GetClientCertificate`,
but it is new in 1.8.
**Release note**
```release-note
With --feature-gates=RotateKubeletClientCertificate=true set, the kubelet will
request a client certificate from the API server during the boot cycle and pause
waiting for the request to be satisfied. It will continually refresh the certificate
as the certificates expiration approaches.
```
Add support for creating resources that are not immediately visible to
naive clients, but must first be initialized by one or more privileged
cluster agents. These controllers can mark the object as initialized,
allowing others to see them.
Permission to override initialization defaults or modify an initializing
object is limited per resource to a virtual subresource "RESOURCE/initialize"
via RBAC.
Initialization is currently alpha.
Automatic merge from submit-queue (batch tested with PRs 46801, 45184, 45930, 46192, 45563)
adds log when --kubeconfig with wrong config
**What this PR does / why we need it**:
easy for troubleshooting
I have set --kubeconfig==/etc/kubernetes/kubelet.conf when copy & paste(the file path is wrong “==/etc/kubernetes/kubelet.conf”), but kubelet start with no error log. I don't know what happend.
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 46801, 45184, 45930, 46192, 45563)
Tweak client-gen to support metrics API
This PR adds support to client-gen for readonly APIs as well as for customizing the resource name used for a given type.
This is required to support the clients generated for `k8s.io/metrics/pkg/apis/metrics`.
cc @caesarxuchao
Currently based on #45180
**Release note**:
```release-note
NONE
```
Add location transformer, config for transformers
Location transformer helps choose the most specific transformer for
read/write operations depending on the path of resource being accessed.
Configuration allows use of --experimental-encryption-provider-config
to set up encryption providers. Only AEAD is supported at the moment.
Add new files to BUILD, AEAD => k8s-aes-gcm
Use group resources to select encryption provider
Update tests for configuration parsing
Remove location transformer
Allow specifying providers per resource group in configuration
Add IdentityTransformer configuration option
Fix minor issues with initial AEAD implementation
Unified parsing of all configurations
Parse configuration using a union struct
Run configuration parsing in APIserver, refactor parsing
More gdoc, fix minor bugs
Add test coverage for combined transformers
Use table driven tests for encryptionconfig
This PR adds the check for local storage request when admitting pods. If
the local storage request exceeds the available resource, pod will be
rejected.
This PR adds the support for allocatable local storage (scratch space).
This feature is only for root file system which is shared by kubernetes
componenets, users' containers and/or images. User could use
--kube-reserved flag to reserve the storage for kube system components.
If the allocatable storage for user's pods is used up, some pods will be
evicted to free the storage resource.
Automatic merge from submit-queue
apiserver: add a webhook implementation of the audit backend
This builds off of #45315 and is intended to implement an interfaced defined in #45766.
TODO:
- [x] Rebase on top of API types PR.
- [x] Rebase on top of API types updates (#46065)
- [x] Rebase on top of feature flag (#46009)
- [x] Rebase on top of audit instrumentation.
- [x] Hook up API server flag or register plugin (depending on #45766)
Features issue https://github.com/kubernetes/features/issues/22
Design proposal https://github.com/kubernetes/community/blob/master/contributors/design-proposals/auditing.md
```release-notes
Webhook added to the API server which omits structured audit log events.
```
/cc @soltysh @timstclair @soltysh @deads2k
Changes the kubelet so it bootstraps off the cert/key specified in the
config file and uses those to request new cert/key pairs from the
Certificate Signing Request API, as well as rotating client certificates
when they approach expiration.
Automatic merge from submit-queue (batch tested with PRs 43505, 45168, 46439, 46677, 46623)
Add TPR to CRD migration helper.
This is a helper for migrating TPR data to CustomResource. It's rather hacky because it requires crossing apiserver boundaries, but doing it this way keeps the mess contained to the TPR code, which is scheduled for deletion anyway.
It's also not completely hands-free because making it resilient enough to be completely automated is too involved to be worth it for an alpha-to-beta migration, and would require investing significant effort to fix up soon-to-be-deleted TPR code. Instead, this feature will be documented as a best-effort helper whose results should be verified by hand.
The intended benefit of this over a totally manual process is that it should be possible to copy TPR data into a CRD without having to tear everything down in the middle. The process would look like this:
1. Upgrade to k8s 1.7. Nothing happens to your TPRs.
1. Create CRD with group/version and resource names that match the TPR. Still nothing happens to your TPRs, as the CRD is hidden by the overlapping TPR.
1. Delete the TPR. The TPR data is converted to CustomResource data, and the CRD begins serving at the same REST path.
Note that the old TPR data is left behind by this process, so watchers should not receive DELETE events. This also means the user can revert to the pre-migration state by recreating the TPR definition.
Ref. https://github.com/kubernetes/kubernetes/issues/45728
Centralize the creation of the dialer during startup.
Have the dialer then passed in to both APIServer and Aggregator.
Aggregator the sets the dialer on its Transport base.
This should allow the SSTunnel to be used but also allow the Aggregation
Auth to work with it.
Depending on Environment InsecureSkipTLSVerify *may* need to be set to
true.
Fixed as few tests to call CreateDialer as part of start-up.
As part of https://github.com/kubernetes/community/pull/132, thsi commit
adds a generic webhook admission controller. This plugin allows for a
completely declarative approach for filtering/matching admission requests
and for matching admission requests, calls out to an external webhook for
handling admission requests.
Automatic merge from submit-queue (batch tested with PRs 46076, 43879, 44897, 46556, 46654)
Local storage plugin
**What this PR does / why we need it**:
Volume plugin implementation for local persistent volumes. Scheduler predicate will direct already-bound PVCs to the node that the local PV is at. PVC binding still happens independently.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*:
Part of #43640
**Release note**:
```
Alpha feature: Local volume plugin allows local directories to be created and consumed as a Persistent Volume. These volumes have node affinity and pods will only be scheduled to the node that the volume is at.
```
Automatic merge from submit-queue (batch tested with PRs 46635, 45619, 46637, 45059, 46415)
Certificate rotation for kubelet server certs.
Replaces the current kubelet server side self signed certs with certs signed by
the Certificate Request Signing API on the API server. Also renews expiring
kubelet server certs as expiration approaches.
Two Points:
1. With `--feature-gates=RotateKubeletServerCertificate=true` set, the kubelet will
request a certificate during the boot cycle and pause waiting for the request to
be satisfied.
2. In order to have the kubelet's certificate signing request auto approved,
`--insecure-experimental-approve-all-kubelet-csrs-for-group=` must be set on
the cluster controller manager. There is an improved mechanism for auto
approval [proposed](https://github.com/kubernetes/kubernetes/issues/45030).
**Release note**:
```release-note
With `--feature-gates=RotateKubeletServerCertificate=true` set, the kubelet will
request a server certificate from the API server during the boot cycle and pause
waiting for the request to be satisfied. It will continually refresh the certificate as
the certificates expiration approaches.
```
Automatic merge from submit-queue (batch tested with PRs 46635, 45619, 46637, 45059, 46415)
migrate group approver to use subject access reviews
WIP, needs test and changes to kubeadm
depends on https://github.com/kubernetes/kubernetes/pull/45514
Automatic merge from submit-queue
kubelet: group all container-runtime-specific flags/options into a separate struct
They don't belong in the KubeletConfig.
This addresses #43253
Automatic merge from submit-queue
fixtypo
**What this PR does / why we need it**:
fix typo seperated -> separated
**Release note**:
```release-note
None
```
Automatic merge from submit-queue (batch tested with PRs 46552, 46608, 46390, 46605, 46459)
Move admission lifecycle to genericapi
**What this PR does / why we need it**: ends the whole sequence of moving some admission plugins to generic api.
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 46561, 46566)
Fix golint errors in cmd/kube-apiserver
**What this PR does / why we need it**:
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
```
Automatic merge from submit-queue (batch tested with PRs 45327, 46217, 46377, 46428, 46588)
ommitting close file while testing manifest
ommitting close file while testing manifest.
Automatic merge from submit-queue (batch tested with PRs 45327, 46217, 46377, 46428, 46588)
Fix comment typo in kube-apiserver and cachesize
**What this PR does / why we need it**:
Fix comment typo in files cmd/kube-apiserver/app/server.go and pkg/registry/cachesize/cachesize.go
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
Not a major issue, just a minor improvement.
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
