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 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
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 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.
```
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
```
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.
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 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
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
```
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.
Automatic merge from submit-queue
Enable shared PID namespace by default for docker pods
**What this PR does / why we need it**: This PR enables PID namespace sharing for docker pods by default, bringing the behavior of docker in line with the other CRI runtimes when used with docker >= 1.13.1.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: ref #1615
**Special notes for your reviewer**: cc @dchen1107 @yujuhong
**Release note**:
```release-note
Kubernetes now shares a single PID namespace among all containers in a pod when running with docker >= 1.13.1. This means processes can now signal processes in other containers in a pod, but it also means that the `kubectl exec {pod} kill 1` pattern will cause the pod to be restarted rather than a single container.
```
Automatic merge from submit-queue (batch tested with PRs 45453, 45307, 44987)
Migrate the docker client code from dockertools to dockershim
Move docker client code from dockertools to dockershim/libdocker. This includes
DockerInterface (renamed to Interface), FakeDockerClient, etc.
This is part of #43234
Automatic merge from submit-queue (batch tested with PRs 45362, 45159, 45321, 45238)
expose kubelet authentication and authorization builders
The kubelet authentication and authorization builder methods are useful for consumers.
@liggitt
Automatic merge from submit-queue
kubelet/get-pods-from-path: correct description of implemention
**What this PR does / why we need it**:
I find this description does not follow the current implementation, it should be describe like this according to my understanding of the source code.
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.
Automatic merge from submit-queue
Delete "hard-coded" default value in flags usage.
**What this PR does / why we need it**:
Some flags of kubernetes components have "hard-coded" default values in their usage info. In fact, [pflag pkg](https://github.com/kubernetes/kubernetes/blob/master/vendor/github.com/spf13/pflag/flag.go#L602-L608) has already added a string `(default value)` automatically in the usage info if the flag is initialized. Then we don't need to hard-code the default value in usage info. After this PR, if we want to update the default value of a flag, we only need to update the flag where it is initialized. `pflag` will update the usage info for us. This will avoid inconsistency.
For example:
Before
```
kubelet -h
...
--node-status-update-frequency duration Specifies how often kubelet posts node status to master. Note: be cautious when changing the constant, it must work with nodeMonitorGracePeriod in nodecontroller. Default: 10s (default 10s)
...
```
After
```
kubelet -h
...
--node-status-update-frequency duration Specifies how often kubelet posts node status to master. Note: be cautious when changing the constant, it must work with nodeMonitorGracePeriod in nodecontroller. (default 10s)
...
```
**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**:
This PR doesn't delete some "hard-coded" default values because they are not explicitly initialized. We still need to hard-code them to give users friendly info.
```
--allow-privileged If true, allow containers to request privileged mode. [default=false]
```
**Release note**:
```release-note
None
```
Automatic merge from submit-queue
Add dockershim only mode
This PR added a `experimental-dockershim` hidden flag in kubelet to run dockershim only.
We introduce this flag mainly for cri validation test. In the future we should compile dockershim into another binary.
@yujuhong @feiskyer @xlgao-zju
/cc @kubernetes/sig-node-pr-reviews
Automatic merge from submit-queue
add rancher credential provider
This adds rancher as a credential provider in kubernetes.
@erictune This might be a good opportunity to discuss adding a provision for people to have their own credential providers that is similar to the new cloud provider changes (https://github.com/kubernetes/community/pull/128). WDYT?
```
release-note
Added Rancher Credential Provider to use Rancher Registry credentials when running in a Rancher cluster
```