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docs/admin/README.md
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@@ -56,6 +56,8 @@ Before choosing a particular guide, here are some things to consider:
- If you are configuring kubernetes on-premises, you will need to consider what [networking
model](networking.md) fits best.
- If you are designing for very high-availability, you may want [clusters in multiple zones](multi-cluster.md).
- You may want to familiarize yourself with the various
[components](cluster-components.md) needed to run a cluster.
## Setting up a cluster

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<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
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<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
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<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<h2>PLEASE NOTE: This document applies to the HEAD of the source tree</h2>
If you are using a released version of Kubernetes, you should
refer to the docs that go with that version.
<strong>
The latest 1.0.x release of this document can be found
[here](http://releases.k8s.io/release-1.0/docs/admin/cluster-components.md).
Documentation for other releases can be found at
[releases.k8s.io](http://releases.k8s.io).
</strong>
--
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# Kubernetes Cluster Admin Guide: Cluster Components
This document outlines the various binary components that need to run to
deliver a functioning Kubernetes cluster.
## Master Components
Master components are those that provide the cluster's control plane. For
example, master components are responsible for making global decisions about the
cluster (e.g., scheduling), and detecting and responding to cluster events
(e.g., starting up a new pod when a replication controller's 'replicas' field is
unsatisfied).
Master components could in theory be run on any node in the cluster. However,
for simplicity, current set up scripts typically start all master components on
the same VM, and does not run user containers on this VM. See
[high-availability.md](high-availability.md) for an example multi-master-VM setup.
Even in the future, when Kubernetes is fully self-hosting, it will probably be
wise to only allow master components to schedule on a subset of nodes, to limit
co-running with user-run pods, reducing the possible scope of a
node-compromising security exploit.
### kube-apiserver
[kube-apiserver](kube-apiserver.md) exposes the Kubernetes API; it is the front-end for the
Kubernetes control plane. It is designed to scale horizontally (i.e., one scales
it by running more of them-- [high-availability.md](high-availability.md)).
### etcd
```etcd``` is used as Kubernetes' backing store. All cluster data is stored here.
Proper administration of a Kubernetes cluster includes a backup plan for etcd's
data.
### kube-controller-manager
[kube-controller-manager](kube-controller-manager.md) is a binary that runs controllers, which are the
background threads that handle routine tasks in the cluster. Logically, each
controller is a separate process, but to reduce the number of moving pieces in
the system, they are all compiled into a single binary and run in a single
process.
These controllers include:
* Node Controller
* Responsible for noticing & responding when nodes go down.
* Replication Controller
* Responsible for maintaining the correct number of pods for every replication
controller object in the system.
* Endpoints Controller
* Populates the Endpoints object (i.e., join Services & Pods).
* Service Account & Token Controllers
* Create default accounts and API access tokens for new namespaces.
* ... and others.
### kube-scheduler
[kube-scheduler](kube-scheduler.md) watches newly created pods that have no node assigned, and
selects a node for them to run on.
### addons
Addons are pods and services that implement cluster features. They don't run on
the master VM, but currently the default setup scripts that make the API calls
to create these pods and services does run on the master VM. See:
[kube-master-addons](../../cluster/saltbase/salt/kube-master-addons/kube-master-addons.sh)
Addon objects are created in the "kube-system" namespace.
Example addons are:
* [DNS](../../cluster/addons/dns/) provides cluster local DNS.
* [kube-ui](../../cluster/addons/kube-ui/) provides a graphical UI for the
cluster.
* [fluentd-elasticsearch](../../cluster/addons/fluentd-elasticsearch) provides
log storage. Also see the [gcp version](../../cluster/addons/fluentd-gcp).
* [cluster-monitoring](../../cluster/addons/cluster-monitoring) provides
monitoring for the cluster.
## Node components
Node components run on every node, maintaining running pods and providing them
the Kubernetes runtime environment.
### kubelet
[kubelet](kubelet.md) is the primary node agent. It:
* Watches for pods that have been assigned to its node (either by apiserver or
or via local configuration file) and:
* Mounts the pod's required volumes
* Downloads the pod's secrets
* Run the pod's containers via docker (or, experimentally, rkt).
* Periodically executes any requested container liveness probes.
* Reports the status of the pod back to the rest of the system, by creating a
"mirror pod" if necessary.
* Reports the status of the node back to the rest of the system.
### kube-proxy
[kube-proxy](kube-proxy.md) enables the Kubernetes service abstraction by maintaining
network rules on the host and performing connection forwarding.
### docker
```docker``` is of course used for actually running containers.
### rkt
```rkt``` is supported experimentally as an alternative to docker.
### monit
```monit``` is a lightweight process babysitting system for keeping kubelet and docker
running.
<!-- BEGIN MUNGE: GENERATED_ANALYTICS -->
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<!-- BEGIN STRIP_FOR_RELEASE -->
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<h2>PLEASE NOTE: This document applies to the HEAD of the source tree</h2>
If you are using a released version of Kubernetes, you should
refer to the docs that go with that version.
<strong>
The latest 1.0.x release of this document can be found
[here](http://releases.k8s.io/release-1.0/docs/admin/kube-apiserver.md).
Documentation for other releases can be found at
[releases.k8s.io](http://releases.k8s.io).
</strong>
--
<!-- END STRIP_FOR_RELEASE -->
<!-- END MUNGE: UNVERSIONED_WARNING -->
## kube-apiserver
### Synopsis
The kubernetes API server validates and configures data
for the api objects which include pods, services, replicationcontrollers, and
others. The API Server services REST operations and provides the frontend to the
cluster's shared state through which all other components interact.
### Options
```
--address=<nil>: DEPRECATED: see --insecure-bind-address instead
--admission-control="": Ordered list of plug-ins to do admission control of resources into cluster. Comma-delimited list of: AlwaysAdmit, AlwaysDeny, DenyExecOnPrivileged, LimitRanger, NamespaceAutoProvision, NamespaceExists, NamespaceLifecycle, ResourceQuota, SecurityContextDeny, ServiceAccount
--admission-control-config-file="": File with admission control configuration.
--advertise-address=<nil>: The IP address on which to advertise the apiserver to members of the cluster. This address must be reachable by the rest of the cluster. If blank, the --bind-address will be used. If --bind-address is unspecified, the host's default interface will be used.
--allow-privileged=false: If true, allow privileged containers.
--api-burst=0: API burst amount for the read only port
--api-prefix="": The prefix for API requests on the server. Default '/api'.
--api-rate=0: API rate limit as QPS for the read only port
--authorization-mode="": Selects how to do authorization on the secure port. One of: AlwaysAllow,AlwaysDeny,ABAC
--authorization-policy-file="": File with authorization policy in csv format, used with --authorization-mode=ABAC, on the secure port.
--basic-auth-file="": If set, the file that will be used to admit requests to the secure port of the API server via http basic authentication.
--bind-address=<nil>: The IP address on which to serve the --read-only-port and --secure-port ports. The associated interface(s) must be reachable by the rest of the cluster, and by CLI/web clients. If blank, all interfaces will be used (0.0.0.0).
--cert-dir="": The directory where the TLS certs are located (by default /var/run/kubernetes). If --tls-cert-file and --tls-private-key-file are provided, this flag will be ignored.
--client-ca-file="": If set, any request presenting a client certificate signed by one of the authorities in the client-ca-file is authenticated with an identity corresponding to the CommonName of the client certificate.
--cloud-config="": The path to the cloud provider configuration file. Empty string for no configuration file.
--cloud-provider="": The provider for cloud services. Empty string for no provider.
--cluster-name="": The instance prefix for the cluster
--cors-allowed-origins=[]: List of allowed origins for CORS, comma separated. An allowed origin can be a regular expression to support subdomain matching. If this list is empty CORS will not be enabled.
--etcd-config="": The config file for the etcd client. Mutually exclusive with -etcd-servers.
--etcd-prefix="": The prefix for all resource paths in etcd.
--etcd-servers=[]: List of etcd servers to watch (http://ip:port), comma separated. Mutually exclusive with -etcd-config
--event-ttl=0: Amount of time to retain events. Default 1 hour.
--external-hostname="": The hostname to use when generating externalized URLs for this master (e.g. Swagger API Docs.)
-h, --help=false: help for kube-apiserver
--insecure-bind-address=<nil>: The IP address on which to serve the --insecure-port (set to 0.0.0.0 for all interfaces). Defaults to localhost.
--insecure-port=0: The port on which to serve unsecured, unauthenticated access. Default 8080. It is assumed that firewall rules are set up such that this port is not reachable from outside of the cluster and that port 443 on the cluster's public address is proxied to this port. This is performed by nginx in the default setup.
--kubelet_certificate_authority="": Path to a cert. file for the certificate authority.
--kubelet_client_certificate="": Path to a client key file for TLS.
--kubelet_client_key="": Path to a client key file for TLS.
--kubelet_https=false: Use https for kubelet connections
--kubelet_port=0: Kubelet port
--kubelet_timeout=0: Timeout for kubelet operations
--long-running-request-regexp="(/|^)((watch|proxy)(/|$)|(logs|portforward|exec)/?$)": A regular expression matching long running requests which should be excluded from maximum inflight request handling.
--master-service-namespace="": The namespace from which the kubernetes master services should be injected into pods
--max-requests-inflight=400: The maximum number of requests in flight at a given time. When the server exceeds this, it rejects requests. Zero for no limit.
--min-request-timeout=1800: An optional field indicating the minimum number of seconds a handler must keep a request open before timing it out. Currently only honored by the watch request handler, which picks a randomized value above this number as the connection timeout, to spread out load.
--old-etcd-prefix="": The previous prefix for all resource paths in etcd, if any.
--port=0: DEPRECATED: see --insecure-port instead
--profiling=true: Enable profiling via web interface host:port/debug/pprof/
--public-address-override=<nil>: DEPRECATED: see --bind-address instead
--runtime-config=: A set of key=value pairs that describe runtime configuration that may be passed to the apiserver. api/<version> key can be used to turn on/off specific api versions. api/all and api/legacy are special keys to control all and legacy api versions respectively.
--secure-port=0: The port on which to serve HTTPS with authentication and authorization. If 0, don't serve HTTPS at all.
--service-account-key-file="": File containing PEM-encoded x509 RSA private or public key, used to verify ServiceAccount tokens. If unspecified, --tls-private-key-file is used.
--service-account-lookup=false: If true, validate ServiceAccount tokens exist in etcd as part of authentication.
--service-cluster-ip-range=<nil>: A CIDR notation IP range from which to assign service cluster IPs. This must not overlap with any IP ranges assigned to nodes for pods.
--service-node-port-range=: A port range to reserve for services with NodePort visibility. Example: '30000-32767'. Inclusive at both ends of the range.
--ssh-keyfile="": If non-empty, use secure SSH proxy to the nodes, using this user keyfile
--ssh-user="": If non-empty, use secure SSH proxy to the nodes, using this user name
--storage-version="": The version to store resources with. Defaults to server preferred
--tls-cert-file="": File containing x509 Certificate for HTTPS. (CA cert, if any, concatenated after server cert). If HTTPS serving is enabled, and --tls-cert-file and --tls-private-key-file are not provided, a self-signed certificate and key are generated for the public address and saved to /var/run/kubernetes.
--tls-private-key-file="": File containing x509 private key matching --tls-cert-file.
--token-auth-file="": If set, the file that will be used to secure the secure port of the API server via token authentication.
```
###### Auto generated by spf13/cobra at 2015-07-06 18:03:28.852677626 +0000 UTC
<!-- BEGIN MUNGE: GENERATED_ANALYTICS -->
[![Analytics](https://kubernetes-site.appspot.com/UA-36037335-10/GitHub/docs/admin/kube-apiserver.md?pixel)]()
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<!-- BEGIN MUNGE: UNVERSIONED_WARNING -->
<!-- BEGIN STRIP_FOR_RELEASE -->
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<h2>PLEASE NOTE: This document applies to the HEAD of the source tree</h2>
If you are using a released version of Kubernetes, you should
refer to the docs that go with that version.
<strong>
The latest 1.0.x release of this document can be found
[here](http://releases.k8s.io/release-1.0/docs/admin/kube-controller-manager.md).
Documentation for other releases can be found at
[releases.k8s.io](http://releases.k8s.io).
</strong>
--
<!-- END STRIP_FOR_RELEASE -->
<!-- END MUNGE: UNVERSIONED_WARNING -->
## kube-controller-manager
### Synopsis
The kubernetes controller manager is a daemon that embeds
the core control loops shipped with Kubernetes. In applications of robotics and
automation, a control loop is a non-terminating loop that regulates the state of
the system. In Kubernetes, a controller is a control loop that watches the shared
state of the cluster through the apiserver and makes changes attempting to move the
current state towards the desired state. Examples of controllers that ship with
Kubernetes today are the replication controller, endpoints controller, namespace
controller, and serviceaccounts controller.
### Options
```
--address=<nil>: The IP address to serve on (set to 0.0.0.0 for all interfaces)
--allocate-node-cidrs=false: Should CIDRs for Pods be allocated and set on the cloud provider.
--cloud-config="": The path to the cloud provider configuration file. Empty string for no configuration file.
--cloud-provider="": The provider for cloud services. Empty string for no provider.
--cluster-cidr=<nil>: CIDR Range for Pods in cluster.
--cluster-name="": The instance prefix for the cluster
--concurrent-endpoint-syncs=0: The number of endpoint syncing operations that will be done concurrently. Larger number = faster endpoint updating, but more CPU (and network) load
--concurrent_rc_syncs=0: The number of replication controllers that are allowed to sync concurrently. Larger number = more responsive replica management, but more CPU (and network) load
--deleting-pods-burst=10: Number of nodes on which pods are bursty deleted in case of node failure. For more details look into RateLimiter.
--deleting-pods-qps=0.1: Number of nodes per second on which pods are deleted in case of node failure.
-h, --help=false: help for kube-controller-manager
--kubeconfig="": Path to kubeconfig file with authorization and master location information.
--master="": The address of the Kubernetes API server (overrides any value in kubeconfig)
--namespace-sync-period=0: The period for syncing namespace life-cycle updates
--node-monitor-grace-period=40s: Amount of time which we allow running Node to be unresponsive before marking it unhealthy. Must be N times more than kubelet's nodeStatusUpdateFrequency, where N means number of retries allowed for kubelet to post node status.
--node-monitor-period=5s: The period for syncing NodeStatus in NodeController.
--node-startup-grace-period=1m0s: Amount of time which we allow starting Node to be unresponsive before marking it unhealthy.
--node-sync-period=0: The period for syncing nodes from cloudprovider. Longer periods will result in fewer calls to cloud provider, but may delay addition of new nodes to cluster.
--pod-eviction-timeout=0: The grace period for deleting pods on failed nodes.
--port=0: The port that the controller-manager's http service runs on
--profiling=true: Enable profiling via web interface host:port/debug/pprof/
--pvclaimbinder-sync-period=0: The period for syncing persistent volumes and persistent volume claims
--register-retry-count=0: The number of retries for initial node registration. Retry interval equals node-sync-period.
--resource-quota-sync-period=0: The period for syncing quota usage status in the system
--root-ca-file="": If set, this root certificate authority will be included in service account's token secret. This must be a valid PEM-encoded CA bundle.
--service-account-private-key-file="": Filename containing a PEM-encoded private RSA key used to sign service account tokens.
```
###### Auto generated by spf13/cobra at 2015-07-06 18:03:31.507732064 +0000 UTC
<!-- BEGIN MUNGE: GENERATED_ANALYTICS -->
[![Analytics](https://kubernetes-site.appspot.com/UA-36037335-10/GitHub/docs/admin/kube-controller-manager.md?pixel)]()
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<!-- BEGIN MUNGE: UNVERSIONED_WARNING -->
<!-- BEGIN STRIP_FOR_RELEASE -->
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<h2>PLEASE NOTE: This document applies to the HEAD of the source tree</h2>
If you are using a released version of Kubernetes, you should
refer to the docs that go with that version.
<strong>
The latest 1.0.x release of this document can be found
[here](http://releases.k8s.io/release-1.0/docs/admin/kube-proxy.md).
Documentation for other releases can be found at
[releases.k8s.io](http://releases.k8s.io).
</strong>
--
<!-- END STRIP_FOR_RELEASE -->
<!-- END MUNGE: UNVERSIONED_WARNING -->
## kube-proxy
### Synopsis
The kubernetes network proxy runs on each node. This
reflects services as defined in the Kubernetes API on each node and can do simple
TCP,UDP stream forwarding or round robin TCP,UDP forwarding across a set of backends.
Service cluster ips and ports are currently found through Docker-links-compatible
environment variables specifying ports opened by the service proxy. There is an optional
addon that provides cluster DNS for these cluster IPs. The user must create a service
with the apiserver API to configure the proxy.
### Options
```
--bind-address=<nil>: The IP address for the proxy server to serve on (set to 0.0.0.0 for all interfaces)
--healthz-bind-address=<nil>: The IP address for the health check server to serve on, defaulting to 127.0.0.1 (set to 0.0.0.0 for all interfaces)
--healthz-port=0: The port to bind the health check server. Use 0 to disable.
-h, --help=false: help for kube-proxy
--kubeconfig="": Path to kubeconfig file with authorization information (the master location is set by the master flag).
--master="": The address of the Kubernetes API server (overrides any value in kubeconfig)
--oom-score-adj=0: The oom_score_adj value for kube-proxy process. Values must be within the range [-1000, 1000]
--proxy-port-range=: Range of host ports (beginPort-endPort, inclusive) that may be consumed in order to proxy service traffic. If unspecified (0-0) then ports will be randomly chosen.
--resource-container="": Absolute name of the resource-only container to create and run the Kube-proxy in (Default: /kube-proxy).
```
###### Auto generated by spf13/cobra at 2015-07-06 18:03:37.657112759 +0000 UTC
<!-- BEGIN MUNGE: GENERATED_ANALYTICS -->
[![Analytics](https://kubernetes-site.appspot.com/UA-36037335-10/GitHub/docs/admin/kube-proxy.md?pixel)]()
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<!-- BEGIN MUNGE: UNVERSIONED_WARNING -->
<!-- BEGIN STRIP_FOR_RELEASE -->
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<h2>PLEASE NOTE: This document applies to the HEAD of the source tree</h2>
If you are using a released version of Kubernetes, you should
refer to the docs that go with that version.
<strong>
The latest 1.0.x release of this document can be found
[here](http://releases.k8s.io/release-1.0/docs/admin/kube-scheduler.md).
Documentation for other releases can be found at
[releases.k8s.io](http://releases.k8s.io).
</strong>
--
<!-- END STRIP_FOR_RELEASE -->
<!-- END MUNGE: UNVERSIONED_WARNING -->
## kube-scheduler
### Synopsis
The kubernetes scheduler is a policy-rich, topology-aware,
workload-specific function that significantly impacts availability, performance,
and capacity. The scheduler needs to take into account individual and collective
resource requirements, quality of service requirements, hardware/software/policy
constraints, affinity and anti-affinity specifications, data locality, inter-workload
interference, deadlines, and so on. Workload-specific requirements will be exposed
through the API as necessary.
### Options
```
--address=<nil>: The IP address to serve on (set to 0.0.0.0 for all interfaces)
--algorithm-provider="": The scheduling algorithm provider to use, one of: DefaultProvider
-h, --help=false: help for kube-scheduler
--kubeconfig="": Path to kubeconfig file with authorization and master location information.
--master="": The address of the Kubernetes API server (overrides any value in kubeconfig)
--policy-config-file="": File with scheduler policy configuration
--port=0: The port that the scheduler's http service runs on
--profiling=true: Enable profiling via web interface host:port/debug/pprof/
```
###### Auto generated by spf13/cobra at 2015-07-06 18:03:39.24859096 +0000 UTC
<!-- BEGIN MUNGE: GENERATED_ANALYTICS -->
[![Analytics](https://kubernetes-site.appspot.com/UA-36037335-10/GitHub/docs/admin/kube-scheduler.md?pixel)]()
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<!-- BEGIN MUNGE: UNVERSIONED_WARNING -->
<!-- BEGIN STRIP_FOR_RELEASE -->
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
width="25" height="25">
<h2>PLEASE NOTE: This document applies to the HEAD of the source tree</h2>
If you are using a released version of Kubernetes, you should
refer to the docs that go with that version.
<strong>
The latest 1.0.x release of this document can be found
[here](http://releases.k8s.io/release-1.0/docs/admin/kubelet.md).
Documentation for other releases can be found at
[releases.k8s.io](http://releases.k8s.io).
</strong>
--
<!-- END STRIP_FOR_RELEASE -->
<!-- END MUNGE: UNVERSIONED_WARNING -->
## kubelet
### Synopsis
The kubelet is the primary "node agent" that runs on each
node. The kubelet works in terms of a PodSpec. A PodSpec is a YAML or JSON object
that describes a pod. The kubelet takes a set of PodSpecs that are provided through
various echanisms (primarily through the apiserver) and ensures that the containers
described in those PodSpecs are running and healthy.
Other than from an PodSpec from the apiserver, there are three ways that a container
manifest can be provided to the Kubelet.
File: Path passed as a flag on the command line. This file is rechecked every 20
seconds (configurable with a flag).
HTTP endpoint: HTTP endpoint passed as a parameter on the command line. This endpoint
is checked every 20 seconds (also configurable with a flag).
HTTP server: The kubelet can also listen for HTTP and respond to a simple API
(underspec'd currently) to submit a new manifest.
### Options
```
--address=<nil>: The IP address for the Kubelet to serve on (set to 0.0.0.0 for all interfaces)
--allow-privileged=false: If true, allow containers to request privileged mode. [default=false]
--api-servers=[]: List of Kubernetes API servers for publishing events, and reading pods and services. (ip:port), comma separated.
--cadvisor-port=0: The port of the localhost cAdvisor endpoint
--cert-dir="": The directory where the TLS certs are located (by default /var/run/kubernetes). If --tls_cert_file and --tls_private_key_file are provided, this flag will be ignored.
--cgroup_root="": Optional root cgroup to use for pods. This is handled by the container runtime on a best effort basis. Default: '', which means use the container runtime default.
--chaos-chance=0: If > 0.0, introduce random client errors and latency. Intended for testing. [default=0.0]
--cloud-config="": The path to the cloud provider configuration file. Empty string for no configuration file.
--cloud-provider="": The provider for cloud services. Empty string for no provider.
--cluster-dns=<nil>: IP address for a cluster DNS server. If set, kubelet will configure all containers to use this for DNS resolution in addition to the host's DNS servers
--cluster-domain="": Domain for this cluster. If set, kubelet will configure all containers to search this domain in addition to the host's search domains
--config="": Path to the config file or directory of files
--configure-cbr0=false: If true, kubelet will configure cbr0 based on Node.Spec.PodCIDR.
--container_runtime="": The container runtime to use. Possible values: 'docker', 'rkt'. Default: 'docker'.
--containerized=false: Experimental support for running kubelet in a container. Intended for testing. [default=false]
--docker-endpoint="": If non-empty, use this for the docker endpoint to communicate with
--docker-exec-handler="": Handler to use when executing a command in a container. Valid values are 'native' and 'nsenter'. Defaults to 'native'.
--enable-debugging-handlers=false: Enables server endpoints for log collection and local running of containers and commands
--enable-server=false: Enable the Kubelet's server
--file-check-frequency=0: Duration between checking config files for new data
--healthz-bind-address=<nil>: The IP address for the healthz server to serve on, defaulting to 127.0.0.1 (set to 0.0.0.0 for all interfaces)
--healthz-port=0: The port of the localhost healthz endpoint
-h, --help=false: help for kubelet
--host-network-sources="": Comma-separated list of sources from which the Kubelet allows pods to use of host network. For all sources use "*" [default="file"]
--hostname-override="": If non-empty, will use this string as identification instead of the actual hostname.
--http-check-frequency=0: Duration between checking http for new data
--image-gc-high-threshold=0: The percent of disk usage after which image garbage collection is always run. Default: 90%%
--image-gc-low-threshold=0: The percent of disk usage before which image garbage collection is never run. Lowest disk usage to garbage collect to. Default: 80%%
--kubeconfig=: Path to a kubeconfig file, specifying how to authenticate to API server (the master location is set by the api-servers flag).
--low-diskspace-threshold-mb=0: The absolute free disk space, in MB, to maintain. When disk space falls below this threshold, new pods would be rejected. Default: 256
--manifest-url="": URL for accessing the container manifest
--master-service-namespace="": The namespace from which the kubernetes master services should be injected into pods
--max-pods=40: Number of Pods that can run on this Kubelet.
--maximum-dead-containers=0: Maximum number of old instances of a containers to retain globally. Each container takes up some disk space. Default: 100.
--maximum-dead-containers-per-container=0: Maximum number of old instances of a container to retain per container. Each container takes up some disk space. Default: 2.
--minimum-container-ttl-duration=0: Minimum age for a finished container before it is garbage collected. Examples: '300ms', '10s' or '2h45m'
--network-plugin="": <Warning: Alpha feature> The name of the network plugin to be invoked for various events in kubelet/pod lifecycle
--node-status-update-frequency=0: 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
--oom-score-adj=0: The oom_score_adj value for kubelet process. Values must be within the range [-1000, 1000]
--pod-cidr="": The CIDR to use for pod IP addresses, only used in standalone mode. In cluster mode, this is obtained from the master.
--pod-infra-container-image="": The image whose network/ipc namespaces containers in each pod will use.
--port=0: The port for the Kubelet to serve on. Note that "kubectl logs" will not work if you set this flag.
--read-only-port=0: The read-only port for the Kubelet to serve on (set to 0 to disable)
--really-crash-for-testing=false: If true, when panics occur crash. Intended for testing.
--register-node=false: Register the node with the apiserver (defaults to true if --api-server is set)
--registry-burst=0: Maximum size of a bursty pulls, temporarily allows pulls to burst to this number, while still not exceeding registry_qps. Only used if --registry_qps > 0
--registry-qps=0: If > 0, limit registry pull QPS to this value. If 0, unlimited. [default=0.0]
--resource-container="": Absolute name of the resource-only container to create and run the Kubelet in (Default: /kubelet).
--root-dir="": Directory path for managing kubelet files (volume mounts,etc).
--runonce=false: If true, exit after spawning pods from local manifests or remote urls. Exclusive with --api_servers, and --enable-server
--streaming-connection-idle-timeout=0: Maximum time a streaming connection can be idle before the connection is automatically closed. Example: '5m'
--sync-frequency=0: Max period between synchronizing running containers and config
--system-container="": Optional resource-only container in which to place all non-kernel processes that are not already in a container. Empty for no container. Rolling back the flag requires a reboot. (Default: "").
--tls-cert-file="": File containing x509 Certificate for HTTPS. (CA cert, if any, concatenated after server cert). If --tls_cert_file and --tls_private_key_file are not provided, a self-signed certificate and key are generated for the public address and saved to the directory passed to --cert_dir.
--tls-private-key-file="": File containing x509 private key matching --tls_cert_file.
```
###### Auto generated by spf13/cobra at 2015-07-06 18:03:36.451093085 +0000 UTC
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