Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>..
kubelet: remove the --docker-exec-handler flag
Stop supporting the "nsenter" exec handler. Only the Docker native exec
handler is supported.
The flag was deprecated in Kubernetes 1.6 and is safe to remove
in Kubernetes 1.9 according to the deprecation policy.
**What this PR does / why we need it**:
**Which issue this PR fixes** : fixes#40229
**Special notes for your reviewer**:
N/A
**Release note**:
```release-note
Remove the --docker-exec-handler flag. Only native exec handler is supported.
```
Automatic merge from submit-queue (batch tested with PRs 52485, 52443, 52597, 52450, 51971). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>..
Some kubelet flags do not accept their default values
Correct the flags and add a round trip test that ensure these do not
break again in the future.
@deads2k as observed when we tried to turn flags into args.
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>..
remove duplicated import
**What this PR does / why we need it**:
**Which issue this PR fixes** : fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
Stop supporting the "nsenter" exec handler. Only the Docker native exec
handler is supported.
The flag was deprecated in Kubernetes 1.6 and is safe to remove
in Kubernetes 1.9 according to the deprecation policy.
Automatic merge from submit-queue (batch tested with PRs 51728, 49202)
Enable CRI-O stats from cAdvisor
**What this PR does / why we need it**:
cAdvisor may support multiple container runtimes (docker, rkt, cri-o, systemd, etc.)
As long as the kubelet continues to run cAdvisor, runtimes with native cAdvisor support may not want to run multiple monitoring agents to avoid performance regression in production. Pending kubelet running a more light-weight monitoring solution, this PR allows remote runtimes to have their stats pulled from cAdvisor when cAdvisor is registered stats provider by introspection of the runtime endpoint.
See issue https://github.com/kubernetes/kubernetes/issues/51798
**Special notes for your reviewer**:
cAdvisor will be bumped to pick up https://github.com/google/cadvisor/pull/1741
At that time, CRI-O will support fetching stats from cAdvisor.
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 51984, 51351, 51873, 51795, 51634)
Revert to using isolated PID namespaces in Docker
**What this PR does / why we need it**: Reverts to the previous docker default of using isolated PID namespaces for containers in a pod. There exist container images that expect always to be PID 1 which we want to support unmodified in 1.8.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes#48937
**Special notes for your reviewer**:
**Release note**:
```release-note
Sharing a PID namespace between containers in a pod is disabled by default in 1.8. To enable for a node, use the --docker-disable-shared-pid=false kubelet flag. Note that PID namespace sharing requires docker >= 1.13.1.
```
A shared PID namespace were enabled by default in the 1.7 when running
with a supported Docker runtime, but a Docker version that supports
a shared namespace was not qualified for use.
Release 1.8 will qualify a docker version supporting shared PID, but we
don't want to cause disruption for container images which expect always
to have PID 1.
Automatic merge from submit-queue (batch tested with PRs 49971, 51357, 51616, 51649, 51372)
Separate feature gates for dynamic kubelet config vs loading from a file
This makes it so these two features can be turned on independently, rather than bundling both under dynamic kubelet config.
fixes: #51664
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 50932, 49610, 51312, 51415, 50705)
Deprecation warnings for auto detecting cloud providers
**What this PR does / why we need it**:
Adds deprecation warnings for auto detecting cloud providers. As part of the initiative for out-of-tree cloud providers, this feature is conflicting since we're shifting the dependency of kubernetes core into cAdvisor. In the future kubelets should be using `--cloud-provider=external` or no cloud provider at all.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes#50986
**Special notes for your reviewer**:
NOTE: I still have to coordinate with sig-node and kubernetes-dev to get approval for this deprecation, I'm only opening this PR since we're close to code freeze and it's something presentable.
**Release note**:
```release-note
Deprecate auto detecting cloud providers in kubelet. Auto detecting cloud providers go against the initiative for out-of-tree cloud providers as we'll now depend on cAdvisor integrations with cloud providers instead of the core repo. In the near future, `--cloud-provider` for kubelet will either be an empty string or `external`.
```
Automatic merge from submit-queue (batch tested with PRs 51054, 51101, 50031, 51296, 51173)
Dynamic Flexvolume plugin discovery, probing with filesystem watch.
**What this PR does / why we need it**: Enables dynamic Flexvolume plugin discovery. This model uses a filesystem watch (fsnotify library), which notifies the system that a probe is necessary only if something changes in the Flexvolume plugin directory.
This PR uses the dependency injection model in https://github.com/kubernetes/kubernetes/pull/49668.
**Release Note**:
```release-note
Dynamic Flexvolume plugin discovery. Flexvolume plugins can now be discovered on the fly rather than only at system initialization time.
```
/sig-storage
/assign @jsafrane @saad-ali
/cc @bassam @chakri-nelluri @kokhang @liggitt @thockin
Automatic merge from submit-queue (batch tested with PRs 50889, 51347, 50582, 51297, 51264)
Change eviction manager to manage one single local storage resource
**What this PR does / why we need it**:
We decided to manage one single resource name, eviction policy should be modified too.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: part of #50818
**Special notes for your reviewer**:
**Release note**:
```release-note
Change eviction manager to manage one single local ephemeral storage resource
```
/assign @jingxu97
The ReadOnlyPort defaulting prevented passing 0 to diable via
the KubeletConfiguraiton struct.
The HealthzPort defaulting prevented passing 0 to disable via the
KubeletConfiguration struct. The documentation also failed to mention
this, but the check is performed in code.
The CAdvisorPort documentation failed to mention that you can pass 0 to
disable.
Automatic merge from submit-queue (batch tested with PRs 50967, 50505, 50706, 51033, 51028)
Revert "Merge pull request #51008 from kubernetes/revert-50789-fix-scheme"
I'm spinning up a cluster right now to test this fix, but I'm pretty sure this was the problem.
There doesn't seem to be a way to confirm from logs, because AFAICT the logs from the hollow kubelet containers are not collected as part of the kubemark test.
**What this PR does / why we need it**:
This reverts commit f4afdecef8, reversing
changes made to e633a1604f.
This also fixes a bug where Kubemark was still using the core api scheme
to manipulate the Kubelet's types, which was the cause of the initial
revert.
**Which issue this PR fixes**: fixes#51007
**Release note**:
```release-note
NONE
```
/cc @shyamjvs @wojtek-t
This reverts commit f4afdecef8, reversing
changes made to e633a1604f.
This also fixes a bug where Kubemark was still using the core api scheme
to manipulate the Kubelet's types, which was the cause of the initial
revert.
Automatic merge from submit-queue (batch tested with PRs 50119, 48366, 47181, 41611, 49547)
Fail on swap enabled and deprecate experimental-fail-swap-on flag
**What this PR does / why we need it**:
* Deprecate the old experimental-fail-swap-on
* Add a new flag fail-swap-on and set it to true
Before this change, we would not fail when swap is on. With this
change we fail for everyone when swap is on, unless they explicitly
set --fail-swap-on to false.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
Fixes#34726
**Special notes for your reviewer**:
**Release note**:
```release-note
Kubelet will by default fail with swap enabled from now on. The experimental flag "--experimental-fail-swap-on" has been deprecated, please set the new "--fail-swap-on" flag to false if you wish to run with /proc/swaps on.
```
* Deprecate the old experimental-fail-swap-on
* Add a new flag fail-swap-on and set it to true
Before this change, we would not fail when swap is on. With this
change we fail for everyone when swap is on, unless they explicitly
set --fail-swap-on to false.
After the kubelet rotates its client cert, it will keep connections
to the API server open indefinitely, causing it to use its old
credentials instead of the new certs
When the kubelet rotates its cert, close down existing connections
to force a new TLS handshake.
Automatic merge from submit-queue (batch tested with PRs 49538, 49708, 47665, 49750, 49528)
Use the core client with version
**What this PR does / why we need it**:
Replace the **deprecated** `clientSet.Core()` with `clientSet.CoreV1()`.
**Which issue this PR fixes**: fixes#49535
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 45813, 49594, 49443, 49167, 47539)
Deprecate keep-terminated-pod-volumes
It was discussed and agreed by sig-storage that
this flag causes unnecessary confusion and is hard to keep
synchornized with controller's attach/detach functionality.
Fixes https://github.com/kubernetes/kubernetes/issues/45615
```release-note
keep-terminated-pod-volumes flag on kubelet is deprecated.
```
Automatic merge from submit-queue (batch tested with PRs 49238, 49595, 43494, 47897, 48905)
Should not set struct pointer directly to interface which may cause potential panic
fix https://github.com/kubernetes/kubernetes/issues/43127 to avoid potential kubelet panic.
In our old implemention, interface `kubeDeps.EventClient ` (interface) will never equals to `nil` even if `eventClient `(struct pointer )was set to `nil`. `kubeDeps.ExternalKubeClient` and `kubeDeps.KubeClient` also have same potential risk.
Automatic merge from submit-queue (batch tested with PRs 48976, 49474, 40050, 49426, 49430)
Use presence of kubeconfig file to toggle standalone mode
Fixes#40049
```release-note
The deprecated --api-servers flag has been removed. Use --kubeconfig to provide API server connection information instead. The --require-kubeconfig flag is now deprecated. The default kubeconfig path is also deprecated. Both --require-kubeconfig and the default kubeconfig path will be removed in Kubernetes v1.10.0.
```
/cc @kubernetes/sig-cluster-lifecycle-misc @kubernetes/sig-node-misc
Automatic merge from submit-queue (batch tested with PRs 48976, 49474, 40050, 49426, 49430)
Remove duplicated import and wrong alias name of api package
**What this PR does / why we need it**:
**Which issue this PR fixes**: fixes#48975
**Special notes for your reviewer**:
/assign @caesarxuchao
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue
Remove flags low-diskspace-threshold-mb and outofdisk-transition-frequency
issue: #48843
This removes two flags replaced by the eviction manager. These have been depreciated for two releases, which I believe correctly follows the kubernetes depreciation guidelines.
```release-note
Remove depreciated flags: --low-diskspace-threshold-mb and --outofdisk-transition-frequency, which are replaced by --eviction-hard
```
cc @mtaufen since I am changing kubelet flags
cc @vishh @derekwaynecarr
/sig node
Automatic merge from submit-queue (batch tested with PRs 48636, 49088, 49251, 49417, 49494)
Fix issues for local storage allocatable feature
This PR fixes the following issues:
1. Use ResourceStorageScratch instead of ResourceStorage API to represent
local storage capacity
2. In eviction manager, use container manager instead of node provider
(kubelet) to retrieve the node capacity and reserved resources. Node
provider (kubelet) has a feature gate so that storagescratch information
may not be exposed if feature gate is not set. On the other hand,
container manager has all the capacity and allocatable resource
information.
This PR fixes issue #47809
Replaces use of --api-servers with --kubeconfig in Kubelet args across
the turnup scripts. In many cases this involves generating a kubeconfig
file for the Kubelet and placing it in the correct location on the node.
This PR fixes the following issues:
1. Use ResourceStorageScratch instead of ResourceStorage API to represent
local storage capacity
2. In eviction manager, use container manager instead of node provider
(kubelet) to retrieve the node capacity and reserved resources. Node
provider (kubelet) has a feature gate so that storagescratch information
may not be exposed if feature gate is not set. On the other hand,
container manager has all the capacity and allocatable resource
information.
This is used by integrators that want to perform partial overrides of
key interfaces. Refactors the run() method to fit the existing style and
preserve the existing behavior, but allow (for instance) client
bootstrap and cert refresh even when some dependencies are injected.
Automatic merge from submit-queue (batch tested with PRs 47694, 47772, 47783, 47803, 47673)
Make different container runtimes constant
Make different container runtimes constant to avoid hardcode
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 47915, 47856, 44086, 47575, 47475)
kubelet should resume csr bootstrap
Right now the kubelet creates a new csr object with the same key every
time it restarts during the bootstrap process. It should resume with the
old csr object if it exists. To do this the name of the csr object must
be stable.
Issue https://github.com/kubernetes/kubernetes/issues/47855
Automatic merge from submit-queue (batch tested with PRs 47922, 47195, 47241, 47095, 47401)
Run cAdvisor on the same interface as kubelet
**What this PR does / why we need it**:
cAdvisor currently binds to all interfaces. Currently the only
solution is to use iptables to block access to the port. We
are better off making cAdvisor to bind to the interface that
kubelet uses for better security.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
Fixes#11710
**Special notes for your reviewer**:
**Release note**:
```release-note
cAdvisor binds only to the interface that kubelet is running on instead of all interfaces.
```
Right now the kubelet creates a new csr object with the same key every
time it restarts during the bootstrap process. It should resume with the
old csr object if it exists. To do this the name of the csr object must
be stable. Also using a list watch here eliminates a race condition
where a watch event is missed and the kubelet stalls.
Automatic merge from submit-queue (batch tested with PRs 46327, 47166)
Fixed typo in comments.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes # N/A
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 46327, 47166)
mark --network-plugin-dir deprecated for kubelet
**What this PR does / why we need it**:
**Which issue this PR fixes** : fixes#43967
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
It was discussed and agreed by sig-storage that
this flag causes unnecessary confusion and is hard to keep
synchornized with controller's attach/detach functionality.
Automatic merge from submit-queue
bazel: stamp multiple packages by using x_defs instead of linkstamp in go_binary rules
**What this PR does / why we need it**: Fixes regression introduced sometime in the last few months that prevented bazel-built clusters from identifying version properly.
It does so by updating the bazelbuild/rules_go and kubernetes/repo-infra dependencies to support using stamp values in `go_binary` `x_defs`, and then changing our `go_binary` rules to use `x_defs` instead of `linkstamp`.
This whole charade is necessary because we need to stamp version information in multiple packages.
This pretty much only affects the bazel build, so it should be low risk.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes#45298
**Special notes for your reviewer**: depends on https://github.com/kubernetes/repo-infra/pull/18; should not be merged before it.
**Release note**:
```release-note
NONE
```
/assign @spxtr @mikedanese
cAdvisor currently binds to all interfaces. Currently the only
solution is to use iptables to block access to the port. We
are better off making cAdvisor to bind to the interface that
kubelet uses for better security.
Fixes#11710
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
```
Kubelet flags are not necessarily appropriate for the KubeletConfiguration
object. For example, this PR also removes HostnameOverride and NodeIP
from KubeletConfiguration. This is a preleminary step to enabling Nodes
to share configurations, as part of the dynamic Kubelet configuration
feature (#29459). Fields that must be unique for each node inhibit
sharing, because their values, by definition, cannot be shared.
Automatic merge from submit-queue
kubelet: change image-gc-high-threshold below docker dm.min_free_space
docker dm.min_free_space defaults to 10%, which "specifies the min free space percent in a thin pool require for new device creation to succeed....Whenever a new a thin pool device is created (during docker pull or during container creation), the Engine checks if the minimum free space is available. If sufficient space is unavailable, then device creation fails and any relevant docker operation fails." [1]
This setting is preventing the storage usage to cross the 90% limit. However, image GC is expected to kick in only beyond image-gc-high-threshold. The image-gc-high-threshold has a default value of 90%, and hence GC never triggers. If image-gc-high-threshold is set to a value lower than (100 - dm.min_free_space)%, GC triggers.
xref https://bugzilla.redhat.com/show_bug.cgi?id=1408309
```release-note
changed kubelet default image-gc-high-threshold to 85% to resolve a conflict with default settings in docker that prevented image garbage collection from resolving low disk space situations when using devicemapper storage.
```
@derekwaynecarr @sdodson @rhvgoyal
Automatic merge from submit-queue
Use realistic value for the memory example of kube-reserved and system-reserved
Use realistic value for the memory example of kube-reserved and system-reserved
Currently, kublet help shows the memory example of
kube-reserved and system-reserved as 150G. This 150G is not realistic
value and it leads misconfiguration or confusion. This patch changes
to example value as 500Mi.
Before(same with system-reserved):
```
--kube-reserved value A set of ResourceName=ResourceQuantity (e.g. cpu=200m,memory=150G) pairs that describe resources reserved for kubernetes system components. Currently only cpu and memory are supported. See http://releases.k8s.io/HEAD/docs/user-guide/compute-resources.md for more detail. [default=none]
```
After(same with system-reserved):
```
--kube-reserved value A set of ResourceName=ResourceQuantity (e.g. cpu=200m,memory=500Mi) pairs that describe resources reserved for kubernetes system components. Currently only cpu and memory are supported. See http://releases.k8s.io/HEAD/docs/user-guide/compute-resources.md for more detail. [default=none]
```
Automatic merge from submit-queue
Eviction Manager Enforces Allocatable Thresholds
This PR modifies the eviction manager to enforce node allocatable thresholds for memory as described in kubernetes/community#348.
This PR should be merged after #41234.
cc @kubernetes/sig-node-pr-reviews @kubernetes/sig-node-feature-requests @vishh
** Why is this a bug/regression**
Kubelet uses `oom_score_adj` to enforce QoS policies. But the `oom_score_adj` is based on overall memory requested, which means that a Burstable pod that requested a lot of memory can lead to OOM kills for Guaranteed pods, which violates QoS. Even worse, we have observed system daemons like kubelet or kube-proxy being killed by the OOM killer.
Without this PR, v1.6 will have node stability issues and regressions in an existing GA feature `out of Resource` handling.
Automatic merge from submit-queue (batch tested with PRs 42443, 38924, 42367, 42391, 42310)
Dell EMC ScaleIO Volume Plugin
**What this PR does / why we need it**
This PR implements the Kubernetes volume plugin to allow pods to seamlessly access and use data stored on ScaleIO volumes. [ScaleIO](https://www.emc.com/storage/scaleio/index.htm) is a software-based storage platform that creates a pool of distributed block storage using locally attached disks on every server. The code for this PR supports persistent volumes using PVs, PVCs, and dynamic provisioning.
You can find examples of how to use and configure the ScaleIO Kubernetes volume plugin in [examples/volumes/scaleio/README.md](examples/volumes/scaleio/README.md).
**Special notes for your reviewer**:
To facilitate code review, commits for source code implementation are separated from other artifacts such as generated, docs, and vendored sources.
```release-note
ScaleIO Kubernetes Volume Plugin added enabling pods to seamlessly access and use data stored on ScaleIO volumes.
```
Automatic merge from submit-queue (batch tested with PRs 41919, 41149, 42350, 42351, 42285)
enable cgroups tiers and node allocatable enforcement on pods by default.
```release-note
Pods are launched in a separate cgroup hierarchy than system services.
```
Depends on #41753
cc @derekwaynecarr
