Merge branch 'master' into env-yaml

.travis.yml

@@ -1,6 +1,6 @@
 language: go
 go:
-  - 1.6.2
+  - 1.7.3
 
 # Don't want default ./... here:
 install:

_data/guides.yml

@@ -71,7 +71,6 @@ toc:
   - docs/user-guide/pods/init-container.md
   - docs/user-guide/configuring-containers.md
   - docs/user-guide/pod-templates.md
-  - docs/user-guide/production-pods.md
   - docs/user-guide/containers.md
   - docs/user-guide/environment-guide/index.md
   - docs/user-guide/compute-resources.md

_data/tasks.yml

@@ -14,6 +14,7 @@ toc:
   - docs/tasks/configure-pod-container/configure-liveness-readiness-probes.md
   - docs/tasks/configure-pod-container/communicate-containers-same-pod.md
   - docs/tasks/configure-pod-container/configure-pod-initialization.md
+  - docs/tasks/configure-pod-container/attach-handler-lifecycle-event.md
 
 - title: Accessing Applications in a Cluster
   section:

docs/admin/salt.md

@@ -6,7 +6,7 @@ title: Configuring Kubernetes with Salt
 
 The Kubernetes cluster can be configured using Salt.
 
-The Salt scripts are shared across multiple hosting providers, so it's important to understand some background information prior to making a modification to ensure your changes do not break hosting Kubernetes across multiple environments.  Depending on where you host your Kubernetes cluster, you may be using different operating systems and different networking configurations.  As a result, it's important to understand some background information before making Salt changes in order to minimize introducing failures for other hosting providers.
+The Salt scripts are shared across multiple hosting providers and depending on where you host your Kubernetes cluster, you may be using different operating systems and different networking configurations. As a result, it's important to understand some background information before making Salt changes in order to minimize introducing failures for other hosting providers.
 
 ## Salt cluster setup
 

docs/api.md

@@ -77,7 +77,7 @@ groups*](https://github.com/kubernetes/kubernetes/blob/{{page.githubbranch}}/doc
 same underlying resources.  The API group is specified in a REST path and in the `apiVersion` field
 of a serialized object.
 
-Currently there are two API groups in use:
+Currently there are several API groups in use:
 
 1. the "core" group, which is at REST path `/api/v1` and is not specified as part of the `apiVersion` field, e.g.
    `apiVersion: v1`.

docs/getting-started-guides/minikube.md

@@ -225,7 +225,7 @@ Any services of type `NodePort` can be accessed over that IP address, on the Nod
 
 To determine the NodePort for your service, you can use a `kubectl` command like this:
 
-`kubectl get service $SERVICE --output='jsonpath="{.spec.ports[0].NodePort}"'`
+`kubectl get service $SERVICE --output='jsonpath="{.spec.ports[0].nodePort}"'`
 
 ## Persistent Volumes
 Minikube supports [PersistentVolumes](http://kubernetes.io/docs/user-guide/persistent-volumes/) of type `hostPath`.

docs/tasks/configure-pod-container/attach-handler-lifecycle-event.md

@@ -0,0 +1,94 @@
+---
+title: Attaching Handlers to Container Lifecycle Events
+---
+
+{% capture overview %}
+
+This page shows how to attach handlers to Container lifecycle events. Kubernetes supports
+the postStart and preStop events. Kubernetes sends the postStart event immediately
+after a Container is started, and it sends the preStop event immediately before the
+Container is terminated.
+
+{% endcapture %}
+
+
+{% capture prerequisites %}
+
+{% include task-tutorial-prereqs.md %}
+
+{% endcapture %}
+
+
+{% capture steps %}
+
+### Defining postStart and preStop handlers
+
+In this exercise, you create a Pod that has one Container. The Container has handlers
+for the postStart and preStop events.
+
+Here is the configuration file for the Pod:
+
+{% include code.html language="yaml" file="lifecycle-events.yaml" ghlink="/docs/tasks/configure-pod-container/lifecycle-events.yaml" %}
+
+In the configuration file, you can see that the postStart command writes a `message`
+file to the Container's `/usr/share` directory. The preStop command shuts down
+nginx gracefully. This is helpful if the Container is being terminated because of a failure.
+
+Create the Pod:
+
+    kubectl create -f http://k8s.io/docs/tasks/configure-pod-container/lifecycle-events.yaml
+
+Verify that the Container in the Pod is running:
+
+    kubectl get pod lifecycle-demo
+
+Get a shell into the Container running in your Pod:
+
+    kubectl exec -it lifecycle-demo -- /bin/bash
+
+In your shell, verify that the `postStart` handler created the `message` file:
+
+    root@lifecycle-demo:/# cat /usr/share/message
+
+The output shows the text written by the postStart handler:
+
+    Hello from the postStart handler
+
+{% endcapture %}
+
+
+
+{% capture discussion %}
+
+### Discussion
+
+Kubernetes sends the postStart event immediately after the Container is created.
+There is no guarantee, however, that the postStart handler is called before
+the Container's entrypoint is called. The postStart handler runs asynchronously
+relative to the Container's code, but Kubernetes' management of the container
+blocks until the postStart handler completes. The Container's status is not
+set to RUNNING until the postStart handler completes.
+
+Kubernetes sends the preStop event immediately before the Container is terminated.
+Kubernetes' management of the Container blocks until the preStop handler completes,
+unless the Pod's grace period expires. For more details, see
+[Termination of Pods](/docs/user-guide/pods/#termination-of-pods).
+
+{% endcapture %}
+
+
+{% capture whatsnext %}
+
+* Learn more about [Container lifecycle hooks](/docs/user-guide/container-environment/.)
+* Learn more about the [lifecycle of a Pod](https://kubernetes.io/docs/user-guide/pod-states/).
+
+
+#### Reference
+ 
+* [Lifecycle](https://kubernetes.io/docs/resources-reference/1_5/#lifecycle-v1)
+* [Container](https://kubernetes.io/docs/resources-reference/1_5/#container-v1)
+* See `terminationGracePeriodSeconds` in [PodSpec](/docs/resources-reference/v1.5/#podspec-v1)
+
+{% endcapture %}
+
+{% include templates/task.md %}

docs/tasks/configure-pod-container/lifecycle-events.yaml

@@ -0,0 +1,33 @@
+apiVersion: v1
+kind: Pod
+metadata:
+  name: lifecycle-demo
+spec:
+  containers:
+  - name: lifecycle-demo-container
+    image: nginx
+
+    lifecycle:
+      postStart:
+        exec:
+          command: ["/bin/sh", "-c", "echo Hello from the postStart handler > /usr/share/message"]
+      preStop:
+        exec:
+          command: ["/usr/sbin/nginx","-s","quit"]
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+

docs/tasks/index.md

@@ -1,5 +1,8 @@
 ---
 title: Tasks
+redirect_from:
+- "/docs/user-guide/production-pods/"
+- "/docs/user-guide/production-pods.html"
 ---
 
 This section of the Kubernetes documentation contains pages that
@@ -17,6 +20,7 @@ single thing, typically by giving a short sequence of steps.
 * [Configuring Liveness and Readiness Probes](/docs/tasks/configure-pod-container/configure-liveness-readiness-probes/)
 * [Communicating Between Pods Running in the Same Container](/docs/tasks/configure-pod-container/communicate-containers-same-pod/)
 * [Configuring Pod Initialization](/docs/tasks/configure-pod-container/configure-pod-initialization/)
+* [Attaching Handlers to Container Lifecycle Events](/docs/tasks/configure-pod-container/attach-handler-lifecycle-event/)
 
 #### Accessing Applications in a Cluster
 

docs/tutorials/kubernetes-basics/explore-intro.html

@@ -28,7 +28,7 @@ title: Viewing Pods and Nodes
 
 			<div class="col-md-8">
 				<h2>Kubernetes Pods</h2>
-				<p>When you created a Deployment in Module <a href="/docs/tutorials/kubernetes-basics/deploy-intro/">2</a>, Kubernetes created a <b>Pod</b> to host your application instance. A Pod is Kubernetes abstraction that represents a group of one or more application containers (such as Docker or rkt), and some shared resources for those containers. Those resources include:</p>
+				<p>When you created a Deployment in Module <a href="/docs/tutorials/kubernetes-basics/deploy-intro/">2</a>, Kubernetes created a <b>Pod</b> to host your application instance. A Pod is a Kubernetes abstraction that represents a group of one or more application containers (such as Docker or rkt), and some shared resources for those containers. Those resources include:</p>
 				<ul>
 					<li>Shared storage, as Volumes</li>
 					<li>Networking, as a unique cluster IP address</li>

docs/user-guide/kubeconfig-file.md

@@ -16,7 +16,7 @@ So in order to easily switch between multiple clusters, for multiple users, a ku
 
 This file contains a series of authentication mechanisms and cluster connection information associated with nicknames.  It also introduces the concept of a tuple of authentication information (user) and cluster connection information called a context that is also associated with a nickname.
 
-Multiple kubeconfig files are allowed, if specified explicitly.  At runtime they are loaded and merged along with override options specified from the command line (see [rules](#loading-and-merging) below).
+Multiple kubeconfig files are allowed, if specified explicitly.  At runtime they are loaded and merged along with override options specified from the command line (see [rules](#loading-and-merging-rules) below).
 
 ## Related discussion
 

docs/user-guide/production-pods.md

@@ -1,245 +0,0 @@
----
-assignees:
-- bgrant0607
-- janetkuo
-- thockin
-title: Working with Containers in Production
----
-
-You've seen [how to configure and deploy pods and containers](/docs/user-guide/configuring-containers), using some of the most common configuration parameters. This section dives into additional features that are especially useful for running applications in production.
-
-* TOC
-{:toc}
-
-## Using a Volume for storage
-
-The container file system only lives as long as the container does, so when a container crashes and restarts, changes to the filesystem will be lost and the container will restart from a clean slate. For more consistent storage that lasts for the life of a Pod, you need a [*volume*](/docs/user-guide/volumes). This is especially important to stateful applications, such as key-value stores and databases.
-
-For example, [Redis](http://redis.io/) is a key-value cache and store, which we use in the [guestbook](https://github.com/kubernetes/kubernetes/tree/{{page.githubbranch}}/examples/guestbook/) and other examples. We can add a volume to it to store data as follows:
-
-{% include code.html language="yaml" file="redis-deployment.yaml" ghlink="/docs/user-guide/redis-deployment.yaml" %}
-
-`emptyDir` volumes live for the lifespan of the [pod](/docs/user-guide/pods), which is longer than the lifespan of any one container, so if the container fails and is restarted, our storage will live on.
-
-In addition to the local disk storage provided by `emptyDir`, Kubernetes supports many different network-attached storage solutions, including PD on GCE and EBS on EC2, which are preferred for critical data, and will handle details such as mounting and unmounting the devices on the nodes. See [the volumes doc](/docs/user-guide/volumes) for more details.
-
-## Distributing credentials
-
-Many applications need credentials, such as passwords, OAuth tokens, and TLS keys, to authenticate with other applications, databases, and services. Storing these credentials in container images or environment variables is less than ideal, since the credentials can then be copied by anyone with access to the image, pod/container specification, host file system, or host Docker daemon.
-
-Kubernetes provides a mechanism, called [*secrets*](/docs/user-guide/secrets), that facilitates delivery of sensitive credentials to applications. A `Secret` is a simple resource containing a map of data. For instance, you can create a simple secret with a username and password as follows:
-
-```shell
-$ kubectl create secret generic mysecret --from-literal=username="admin",password="1234"
-secret "mysecret" created
-```
-
-This is equivalent to `kubectl create -f`:
-
-```yaml
-apiVersion: v1
-kind: Secret
-metadata:
-  name: mysecret
-type: Opaque
-data:
-  username: YWRtaW4=
-  password: MTIzNA==
-```
-
-As with other resources, the created secret can be viewed with `get`:
-
-```shell
-$ kubectl get secrets
-NAME                  TYPE                                  DATA      AGE
-default-token-zirbw   kubernetes.io/service-account-token   3         3h
-mysecret              Opaque                                2         2m
-```
-
-To use the secret, you need to reference it in a pod or pod template. The `secret` volume source enables you to mount it as an in-memory directory into your containers.
-
-{% include code.html language="yaml" file="redis-secret-deployment.yaml" ghlink="/docs/user-guide/redis-secret-deployment.yaml" %}
-
-For more details, see the [secrets document](/docs/user-guide/secrets), [example](/docs/user-guide/secrets/) and [design doc](https://github.com/kubernetes/kubernetes/blob/{{page.githubbranch}}/docs/design/secrets.md).
-
-## Authenticating with a private image registry
-
-Secrets can also be used to pass [image registry credentials](/docs/user-guide/images/#using-a-private-registry).
-
-The easiest way to create a secret for Docker registry is:
-
-```shell
-$ kubectl create secret docker-registry myregistrykey --docker-username=janedoe --docker-password=●●●●●●●●●●● --docker-email=jdoe@example.com
-secret "myregistrykey" created
-```
-
-Alternatively, you can do the equivalent with the following steps. First, create a `.docker/config.json`, such as by running `docker login <registry.domain>`.
-Then put the resulting `.docker/config.json` file into a [secret resource](secrets.md).  For example:
-
-```shell
-$ docker login
-Username: janedoe
-Password: ●●●●●●●●●●●
-Email: jdoe@example.com
-WARNING: login credentials saved in /Users/jdoe/.docker/config.json.
-Login Succeeded
-
-$ echo $(cat ~/.docker/config.json)
-{ "https://index.docker.io/v1/": { "auth": "ZmFrZXBhc3N3b3JkMTIK", "email": "jdoe@example.com" } }
-
-$ cat ~/.docker/config.json | base64
-eyAiaHR0cHM6Ly9pbmRleC5kb2NrZXIuaW8vdjEvIjogeyAiYXV0aCI6ICJabUZyWlhCaGMzTjNiM0prTVRJSyIsICJlbWFpbCI6ICJqZG9lQGV4YW1wbGUuY29tIiB9IH0K
-
-$ cat > /tmp/image-pull-secret.yaml <<EOF
-apiVersion: v1
-kind: Secret
-metadata:
-  name: myregistrykey
-data:
-  .dockerconfigjson: eyAiaHR0cHM6Ly9pbmRleC5kb2NrZXIuaW8vdjEvIjogeyAiYXV0aCI6ICJabUZyWlhCaGMzTjNiM0prTVRJSyIsICJlbWFpbCI6ICJqZG9lQGV4YW1wbGUuY29tIiB9IH0K
-type: kubernetes.io/dockerconfigjson
-EOF
-
-$ kubectl create -f /tmp/image-pull-secret.yaml
-secret "myregistrykey" created
-```
-
-Now, you can create pods which reference that secret by adding an `imagePullSecrets`
-section to a pod definition.
-
-```yaml
-apiVersion: v1
-kind: Pod
-metadata:
-  name: foo
-spec:
-  containers:
-    - name: foo
-      image: janedoe/awesomeapp:v1
-  imagePullSecrets:
-    - name: myregistrykey
-```
-
-## Helper containers
-
-[Pods](/docs/user-guide/pods) support running multiple containers co-located together. They can be used to host vertically integrated application stacks, but their primary motivation is to support auxiliary helper programs that assist the primary application. Typical examples are data pullers, data pushers, and proxies.
-
-Such containers typically need to communicate with one another, often through the file system. This can be achieved by mounting the same volume into both containers. An example of this pattern would be a web server with a [program that polls a git repository](http://releases.k8s.io/{{page.githubbranch}}/contrib/git-sync/) for new updates:
-
-```yaml
-apiVersion: extensions/v1beta1
-kind: Deployment
-metadata:
-  name: my-nginx
-spec:
-  template:
-    metadata:
-      labels:
-        app: nginx
-    spec:
-      volumes:
-      - name: www-data
-        emptyDir: {}
-      containers:
-      - name: nginx
-        image: nginx
-        # This container reads from the www-data volume
-        volumeMounts:
-        - mountPath: /srv/www
-          name: www-data
-          readOnly: true
-      - name: git-monitor
-        image: myrepo/git-monitor
-        env:
-        - name: GIT_REPO
-          value: http://github.com/some/repo.git
-        # This container writes to the www-data volume
-        volumeMounts:
-        - mountPath: /data
-          name: www-data
-```
-
-More examples can be found in our [blog article](http://blog.kubernetes.io/2015/06/the-distributed-system-toolkit-patterns.html) and [presentation slides](http://www.slideshare.net/Docker/slideshare-burns).
-
-## Resource management
-
-Kubernetes's scheduler will place applications only where they have adequate CPU and memory, but it can only do so if it knows how much [resources they require](/docs/user-guide/compute-resources). The consequence of specifying too little CPU is that the containers could be starved of CPU if too many other containers were scheduled onto the same node. Similarly, containers could die unpredictably due to running out of memory if no memory were requested, which can be especially likely for large-memory applications.
-
-If no resource requirements are specified, a nominal amount of resources is assumed. (This default is applied via a [LimitRange](/docs/admin/limitrange/) for the default [Namespace](/docs/user-guide/namespaces). It can be viewed with `kubectl describe limitrange limits`.) You may explicitly specify the amount of resources required as follows:
-
-{% include code.html language="yaml" file="redis-resource-deployment.yaml" ghlink="/docs/user-guide/redis-resource-deployment.yaml" %}
-
-The container will die due to OOM (out of memory) if it exceeds its specified limit, so specifying a value a little higher than expected generally improves reliability. By specifying request, pod is guaranteed to be able to use that much of resource when needed. See [Resource QoS](https://github.com/kubernetes/kubernetes/blob/{{page.githubbranch}}/docs/design/resource-qos.md) for the difference between resource limits and requests.
-
-If you're not sure how much resources to request, you can first launch the application without specifying resources, and use [resource usage monitoring](/docs/user-guide/monitoring) to determine appropriate values.
-
-## Liveness and readiness probes (aka health checks)
-
-Many applications running for long periods of time eventually transition to broken states, and cannot recover except by restarting them. Kubernetes provides [*liveness probes*](/docs/user-guide/pod-states/#container-probes) to detect and remedy such situations.
-
-A common way to probe an application is using HTTP, which can be specified as follows:
-
-{% include code.html language="yaml" file="nginx-probe-deployment.yaml" ghlink="/docs/user-guide/nginx-probe-deployment.yaml" %}
-
-Other times, applications are only temporarily unable to serve, and will recover on their own. Typically in such cases you'd prefer not to kill the application, but don't want to send it requests, either, since the application won't respond correctly or at all. A common such scenario is loading large data or configuration files during application startup. Kubernetes provides *readiness probes* to detect and mitigate such situations. Readiness probes are configured similarly to liveness probes, just using the `readinessProbe` field. A pod with containers reporting that they are not ready will not receive traffic through Kubernetes [services](/docs/user-guide/connecting-applications).
-
-For more details (e.g., how to specify command-based probes), see the [example in the walkthrough](/docs/user-guide/walkthrough/k8s201/#health-checking), the [standalone example](/docs/user-guide/liveness/), and the [documentation](/docs/user-guide/pod-states/#container-probes).
-
-## Handling initialization
-
-Applications often need a set of initialization steps prior to performing their day job. This may include:
-
-* Waiting for other components (like a database or web service) to be available
-* Performing configuration templating from environment variables into a config file
-* Registering the pod into a central database, or fetching remote configuration from that database
-* Downloading application dependencies, seed data, or preconfiguring disk
-
-Kubernetes now includes a beta feature known as **init containers**, which are one or more containers in a pod that get a chance to run and initialize shared volumes prior to the other application containers starting.  An init container is exactly like a regular container, except that it always runs to completion and each init container must complete successfully before the next one is started. If the init container fails (exits with a non-zero exit code) on a `RestartNever` pod the pod will fail - otherwise it will be restarted until it succeeds or the user deletes the pod.
-
-Since init containers are a beta feature, they are specified by setting the `pod.beta.kubernetes.io/init-containers` annotation on a pod (or replica set, deployment, daemon set, pet set, or job). The value of the annotation must be a string containing a JSON array of container definitions:
-
-{% include code.html language="yaml" file="nginx-init-containers.yaml" ghlink="/docs/user-guide/nginx-init-containers.yaml" %}
-
-The status of the init containers is returned as another annotation - `pod.beta.kubernetes.io/init-container-statuses` -- as an array of the container statuses (similar to the `status.containerStatuses` field).
-
-Init containers support all of the same features as normal containers, including resource limits, volumes, and security settings. The resource requests and limits for an init container are handled slightly different than normal containers since init containers are run one at a time instead of all at once - any limits or quotas will be applied based on the largest init container resource quantity, rather than as the sum of quantities. Init containers do not support readiness probes since they will run to completion before the pod can be ready.
-
-[Complete Init Container Documentation](/docs/user-guide/pods/init-container/)
-
-
-## Lifecycle hooks and termination notice
-
-Of course, nodes and applications may fail at any time, but many applications benefit from clean shutdown, such as to complete in-flight requests, when the termination of the application is deliberate. To support such cases, Kubernetes supports two kinds of notifications:
-
-* Kubernetes will send SIGTERM to applications, which can be handled in order to effect graceful termination. SIGKILL is sent a configurable number of seconds later if the application does not terminate sooner (defaults to 30 seconds, controlled by `spec.terminationGracePeriodSeconds`).
-* Kubernetes supports the (optional) specification of a [*pre-stop lifecycle hook*](/docs/user-guide/container-environment/#container-hooks), which will execute prior to sending SIGTERM.
-
-The specification of a pre-stop hook is similar to that of probes, but without the timing-related parameters. For example:
-
-{% include code.html language="yaml" file="nginx-lifecycle-deployment.yaml" ghlink="/docs/user-guide/nginx-lifecycle-deployment.yaml" %}
-
-## Termination message
-
-In order to achieve a reasonably high level of availability, especially for actively developed applications, it's important to debug failures quickly. Kubernetes can speed debugging by surfacing causes of fatal errors in a way that can be display using [`kubectl`](/docs/user-guide/kubectl/) or the [UI](/docs/user-guide/ui), in addition to general [log collection](/docs/user-guide/logging/overview). It is possible to specify a `terminationMessagePath` where a container will write its 'death rattle'?, such as assertion failure messages, stack traces, exceptions, and so on. The default path is `/dev/termination-log`.
-
-Here is a toy example:
-
-{% include code.html language="yaml" file="pod-w-message.yaml" ghlink="/docs/user-guide/pod-w-message.yaml" %}
-
-The message is recorded along with the other state of the last (i.e., most recent) termination:
-
-```shell
-{% raw %}
-$ kubectl create -f ./pod-w-message.yaml
-pod "pod-w-message" created
-$ sleep 70
-$ kubectl get pods/pod-w-message -o go-template="{{range .status.containerStatuses}}{{.lastState.terminated.message}}{{end}}"
-Sleep expired
-$ kubectl get pods/pod-w-message -o go-template="{{range .status.containerStatuses}}{{.lastState.terminated.exitCode}}{{end}}"
-0
-{% endraw %}
-```
-
-## What's next?
-
-[Learn more about managing deployments.](/docs/user-guide/managing-deployments)