docs: add doc about cri-annotation-support

Signed-off-by: Starnop <[email protected]>
AliyunContainerService · Sep 14, 2018 · de92e30 · de92e30
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diff --git a/docs/kubernetes/pouch_cri_annotation_support.md b/docs/kubernetes/pouch_cri_annotation_support.md
@@ -0,0 +1,166 @@
+# CRI ANNOTATIONS SUPPORTED CHANGELOG
+
+* [Overview](#overview "Overview")
+* [The Annotations Supported](#the-annotations-supported "The Annotations Supported")
+  * [Make runtime choosing supported](#make-runtime-choosing-supported "Make runtime choosing supported")
+  * [Make lxcfs configurable supported](#make-lxcfs-configurable-supported "Make lxcfs configurable supported")
+* [Pull Request](#pull-request "Pull Request")
+
+## Overview
+
+Currently, PouchContainer has lots of advantages over other container runtimes, such as:
+
+* resource review isolation via lxcfs
+* runtime choosing for runc-based container or runv-based containers
+* and so on
+
+While actually in kubernetes, there is no related API to support these feature.
+
+While for these extended features in Kubernetes, Kubernetes has a hiden way to support this: make user-defined parameters in annotations field in pod's definition.
+When CRI manager deals the annotation details, it could pass these parameters to container manager, and container manager definitely implement these features very well.
+
+So, we need to accomplish the following things:
+
+* define the specific naming in annotations for each feature;
+* implement the transformation in CRI manager and pass them to container manager.
+
+Kubernetes Version: V1.10.0+
+
+## The Annotations Supported
+
+| Requirement                       | Field definition                             | Pull Request                               |
+|-----------------------------------|----------------------------------------------|--------------------------------------------|
+| make runtime choosing supported   | KubernetesRuntime = "io.kubernetes.runtime"  | https://github.com/alibaba/pouch/pull/1593 |
+| make lxcfs configurable supported | LxcfsEnabled = "io.kubernetes.lxcfs.enabled" | https://github.com/alibaba/pouch/pull/2210 |
+
+### Make runtime choosing supported
+
+#### What To Solve
+
+1. Support choosing the runtime for a container by making runtime choosing supported.
+
+#### How to verify it
+
+1. Prerequisites Installation, the runtime binaries you will use is necessary.
+
+2. You should start pouchd with the configuration like this:
+
+```
+pouchd --enable-cri --cri-version v1alpha2 --add-runtime runv=runv >pouchd.log 2>&1  &
+```
+
+3. After setting up your kubernetes cluster, you can create a deployment like this :
+
+```
+# cat pouch-runtime.yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: pouch-runtime
+  labels:
+    pouch: pouch-runtime
+spec:
+  selector:
+    matchLabels:
+      pouch: pouch-runtime
+  template:
+    metadata:
+      labels:
+        pouch: pouch-runtime
+      annotations:
+        io.kubernetes.runtime: runv
+    spec:
+      containers:
+      - name: pouch-runtime
+        image: docker.io/library/nginx:latest
+        ports:
+        - containerPort: 80
+                  
+# kubectl create -f pouch-runtime.yaml
+```
+
+4. Use command `pouch ps` to observe the runtime of the container and use command `uname -a` to view the system info.
+
+```
+# pouch ps
+Name                                                                                                     ID       Status          Created          Image                                                                 Runtime
+k8s_pouch-runtime_pouch-runtime-76c8d4d79b-6l5w7_default_47e8f918-b7c8-11e8-b238-42010a8c0004_0          59ce1d   Up 8 seconds    9 seconds ago    docker.io/library/nginx:latest                                        runv
+k8s_POD_pouch-runtime-76c8d4d79b-6l5w7_default_47e8f918-b7c8-11e8-b238-42010a8c0004_0                    9492db   Up 21 seconds   29 seconds ago   registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0   runv
+
+// the system info for host
+# uname -a
+Linux k8s 4.15.0-1019-gcp #20~16.04.1-Ubuntu SMP Thu Aug 30 11:52:19 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
+
+// the system info for the pod with runv 
+# kubectl exec -it pouch-runtime-76c8d4d79b-6l5w7 -- bash
+$ uname -a
+Linux pouch-runtime-76c8d4d79b-6l5w7 4.12.4-hyper #18 SMP Mon Sep 4 15:10:13 CST 2017 x86_64 GNU/Linux
+
+```
+
+### Make lxcfs configurable supported
+
+#### What To Solve
+
+1. Support resource review isolation via lxcfs in CRI Manager by making lxcfs configurable supported.
+
+#### How to verify it
+
+1. Prerequisites Installation and make sure your lxcfs service is running.
+
+2. Enable pouchd lxcfs (with --enable-lxcfs flag).
+
+3. After setting up your kubernetes cluster, you can create a deployment like this :
+
+```
+# cat pouch-lxcfs.yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: pouch-lxcfs
+  labels:
+    pouch: pouch-lxcfs
+spec:
+  selector:
+    matchLabels:
+      pouch: pouch-lxcfs
+  template:
+    metadata:
+      labels:
+        pouch: pouch-lxcfs
+      annotations:
+        io.kubernetes.lxcfs.enabled: "true"
+    spec:
+      containers:
+      - name: pouch-lxcfs
+        image: docker.io/library/busybox:latest
+        command:
+          - top
+        resources:
+          requests:
+            memory: "256Mi"
+          limits:
+            memory: "256Mi"
+
+# kubectl create -f pouch-lxcfs.yaml
+```
+
+4. View the results.
+
+```
+# pouch ps
+Name                                                                                                           ID       Status       Created       Image                                                                 Runtime
+k8s_pouch_pouch-5ddd8fc467-rmtcw_default_bc4b7972-b181-11e8-adae-42010a8c0003_0                                5391a9   Up 8 hours   8 hours ago   docker.io/library/busybox:latest                                      runc
+k8s_POD_pouch-5ddd8fc467-rmtcw_default_bc4b7972-b181-11e8-adae-42010a8c0003_0                                  60a833   Up 8 hours   8 hours ago   registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0   runc
+
+# pouch exec k8s_pouch_pouch-5ddd8fc467-rmtcw_default_bc4b7972-b181-11e8-adae-42010a8c0003_0 cat /proc/meminfo 
+MemTotal:         262144 kB
+MemFree:          261368 kB
+MemAvailable:     261368 kB
+......
+```
+
+## Pull Request
+
+* feature: make runtime choosing supported [#1593](https://github.com/alibaba/pouch/pull/1593)
+* feature: make lxcfs configurable supportd in CRI [#2210](https://github.com/alibaba/pouch/pull/2210)
diff --git a/docs/kubernetes/pouch_cri_api_changelog.md b/docs/kubernetes/pouch_cri_api_changelog.md
@@ -311,4 +311,4 @@ message Mount {
 + feature: extend cri apis for special needs [#1617](https://github.com/alibaba/pouch/pull/1617)
 + feature: extend cri apis for remove volume [#2124](https://github.com/alibaba/pouch/pull/2124)
 + feature: extend cri apis for support quotaID [#2138](https://github.com/alibaba/pouch/pull/2138)
-
++ feature: extend cri apis for get envs [#2163](https://github.com/alibaba/pouch/pull/2163)