Merge branch 'master' of https://github.com/kubernetes/kubernetes.git…

…hub.io into release-1.8 * 'master' of https://github.com/kubernetes/kubernetes.github.io: fix noindex for vnext-staging (#4640) Add network overlay details to cloud routes flag Revert "Update volumes.md" add examples for interpod configurations (#4557) Update "readonly" in abac
kubernetes · Aug 4, 2017 · 08e6c4c · 08e6c4c
2 parents 3641330 + 8825d5a
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diff --git a/docs/admin/authorization/abac.md b/docs/admin/authorization/abac.md
@@ -45,7 +45,7 @@ properties:
         - Wildcard: 
           - `*` matches all non-resource requests.
           - `/foo/*` matches all subpaths of `/foo/`.
-    - `readonly`, type boolean, when true, means that the policy only applies to get, list, and watch operations.
+    - `readonly`, type boolean, when true, means that the Resource-matching policy only applies to get, list, and watch operations, Non-resource-matching policy only applies to get operation.
 
 **NOTES:** An unset property is the same as a property set to the zero value for its type
 (e.g. empty string, 0, false). However, unset should be preferred for

diff --git a/docs/admin/kube-controller-manager.md b/docs/admin/kube-controller-manager.md
@@ -45,7 +45,7 @@ kube-controller-manager
       --concurrent-service-syncs int32                                    The number of services that are allowed to sync concurrently. Larger number = more responsive service management, but more CPU (and network) load (default 1)
       --concurrent-serviceaccount-token-syncs int32                       The number of service account token objects that are allowed to sync concurrently. Larger number = more responsive token generation, but more CPU (and network) load (default 5)
       --concurrent_rc_syncs int32                                         The number of replication controllers that are allowed to sync concurrently. Larger number = more responsive replica management, but more CPU (and network) load (default 5)
-      --configure-cloud-routes                                            Should CIDRs allocated by allocate-node-cidrs be configured on the cloud provider. (default true)
+      --configure-cloud-routes                                            Should CIDRs allocated by allocate-node-cidrs be configured on the cloud provider. If using a network overlay which will handle routing independent of the cloud provider, set this to false. (default true)
       --contention-profiling                                              Enable lock contention profiling, if profiling is enabled
       --controller-start-interval duration                                Interval between starting controller managers.
       --controllers stringSlice                                           A list of controllers to enable.  '*' enables all on-by-default controllers, 'foo' enables the controller named 'foo', '-foo' disables the controller named 'foo'.

diff --git a/docs/concepts/configuration/assign-pod-node.md b/docs/concepts/configuration/assign-pod-node.md
@@ -168,7 +168,7 @@ and an example `preferredDuringSchedulingIgnoredDuringExecution` anti-affinity w
 Inter-pod affinity is specified as field `podAffinity` of field `affinity` in the PodSpec.
 And inter-pod anti-affinity is specified as field `podAntiAffinity` of field `affinity` in the PodSpec.
 
-Here's an example of a pod that uses pod affinity:
+#### An example of a pod that uses pod affinity:
 
 {% include code.html language="yaml" file="pod-with-pod-affinity.yaml" ghlink="/docs/concepts/configuration/pod-with-pod-affinity.yaml" %}
 
@@ -206,6 +206,95 @@ If defined but empty, it means "all namespaces."
 All `matchExpressions` associated with `requiredDuringSchedulingIgnoredDuringExecution` affinity and anti-affinity
 must be satisfied for the pod to schedule onto a node.
 
+#### More Practical Use-cases 
+
+Interpod Affinity and AnitAffinity can be even more useful when they are used with higher
+level collections such as ReplicaSets, Statefulsets, Deployments, etc.  One can easily configure that a set of workloads should
+be co-located in the same defined topology, eg., the same node. 
+
+##### Always co-located in the same node
+
+In a three node cluster, a web application has in-memory cache such as redis, we want the web-servers to be co-located with the cache as much as possible. 
+Here is the yaml snippet of a simple redis deployment with three replicas and selector label `app=store`
+
+```yaml
+apiVersion: apps/v1beta1 # for versions before 1.6.0 use extensions/v1beta1
+kind: Deployment
+metadata:
+  name: redis-cache
+spec:
+  replicas: 3
+  template:
+    metadata:
+      labels:
+        app: store
+    spec:
+      containers:
+      - name: redis-server
+        image: redis:3.2-alpine
+```
+
+Below yaml snippet of the webserver deployment has `podAffinity` configured, this informs the scheduler that all its replicas are to be 
+co-located with pods that has selector label `app=store` 
+
+```yaml
+apiVersion: apps/v1beta1 # for versions before 1.6.0 use extensions/v1beta1
+kind: Deployment
+metadata:
+  name: web-server
+spec:
+  replicas: 3
+  template:
+    metadata:
+      labels:
+        app: web-store
+    spec:
+      affinity:
+        podAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+          - labelSelector:
+              matchExpressions:
+              - key: app
+                operator: In
+                values:
+                - store
+            topologyKey: "kubernetes.io/hostname"
+      containers:
+      - name: web-app
+```
+
+if we create the above two deployments, our three node cluster could look like below.
+
+|       node-1         |       node-2        |       node-3       |
+|:--------------------:|:-------------------:|:------------------:|
+| *webserver-1*        |   *webserver-2*     |    *webserver-3*   |
+|  *cache-1*           |     *cache-2*       |     *cache-3*      |
+
+As you can see, all the 3 replicas of the `web-server` are automatically co-located with the cache as expected. 
+
+```
+$kubectl get pods -o wide
+NAME                           READY     STATUS    RESTARTS   AGE       IP           NODE
+redis-cache-1450370735-6dzlj   1/1       Running   0          8m        10.192.4.2   kube-node-3
+redis-cache-1450370735-j2j96   1/1       Running   0          8m        10.192.2.2   kube-node-1
+redis-cache-1450370735-z73mh   1/1       Running   0          8m        10.192.3.1   kube-node-2
+web-server-1287567482-5d4dz    1/1       Running   0          7m        10.192.2.3   kube-node-1
+web-server-1287567482-6f7v5    1/1       Running   0          7m        10.192.4.3   kube-node-3
+web-server-1287567482-s330j    1/1       Running   0          7m        10.192.3.2   kube-node-2
+```
+
+Best practice is to configure these highly available stateful workloads such as redis with AntiAffinity rules for more guaranteed spreading, which we will see in the next section.
+
+##### Never co-located in the same node
+
+Highly Available database statefulset has one master and three replicas, one may prefer none of the database instances to be co-located in the same node.
+
+|       node-1         |       node-2        |       node-3       |       node-4       |
+|:--------------------:|:-------------------:|:------------------:|:------------------:|
+| *DB-MASTER*          | *DB-REPLICA-1*      | *DB-REPLICA-2*     | *DB-REPLICA-3*     |
+
+[Here](https://kubernetes.io/docs/tutorials/stateful-application/zookeeper/#tolerating-node-failure) is an example of zookeper statefulset configured with anti-affinity for high availablity.
+
 For more information on inter-pod affinity/anti-affinity, see the design doc
 [here](https://git.k8s.io/community/contributors/design-proposals/podaffinity.md).
 

diff --git a/docs/concepts/storage/volumes.md b/docs/concepts/storage/volumes.md
@@ -289,10 +289,10 @@ spec:
 
 ### nfs
 
-A `nfs` volume allows an existing NFS (Network File System) share to be
+An `nfs` volume allows an existing NFS (Network File System) share to be
 mounted into your pod. Unlike `emptyDir`, which is erased when a Pod is
 removed, the contents of an `nfs` volume are preserved and the volume is merely
-unmounted.  This means that a NFS volume can be pre-populated with data, and
+unmounted.  This means that an NFS volume can be pre-populated with data, and
 that data can be "handed off" between pods.  NFS can be mounted by multiple
 writers simultaneously.
 
@@ -322,7 +322,7 @@ See the [iSCSI example](https://github.com/kubernetes/kubernetes/tree/{{page.git
 
 ### fc (fibre channel)
 
-A `fc` volume allows an existing fibre channel volume to be mounted into your pod.
+An `fc` volume allows an existing fibre channel volume to be mounted into your pod.
 You can specify single or multiple target World Wide Names to the parameter
 targetWWNs in your volume configuration. If multiple WWNs are specified,
 targetWWNs expects that those WWNs form multipath connection.
@@ -365,7 +365,7 @@ See the [GlusterFS example](https://github.com/kubernetes/kubernetes/tree/{{page
 
 ### rbd
 
-A `rbd` volume allows a [Rados Block
+An `rbd` volume allows a [Rados Block
 Device](http://ceph.com/docs/master/rbd/rbd/) volume to be mounted into your
 pod.  Unlike `emptyDir`, which is erased when a Pod is removed, the contents of
 a `rbd` volume are preserved and the volume is merely unmounted.  This

diff --git a/netlify.toml b/netlify.toml
@@ -4,6 +4,3 @@
 
 [context.deploy-preview]
   command = "make build-preview"
-
-[context.vnext-staging]
-  command = "make build && cp netlify_noindex_headers.txt _site/_headers"
diff --git a/netlify_noindex_headers.txt b/netlify_noindex_headers.txt
@@ -0,0 +1,3 @@
+# Prevent bots from indexing site
+/*
+  X-Robots-Tag: noindex