1.2 additions for getting-started-guides/ and new non-Markdown files for user-guides

2016-03-06 17:55:12 +00:00
parent 97c728d343
commit a6f6fd01cd
78 changed files with 2314 additions and 975 deletions
@@ -0,0 +1,99 @@
+---
+---
+
+# Notes on Different UX with rkt container runtime
+
+### Doesn't support ENTRYPOINT + CMD feature
+
+To run a Docker image, rkt will convert it into [App Container Image (ACI) format](https://github.com/appc/spec/blob/master/SPEC.md) first.
+However, during the conversion, the `ENTRYPOINT` and `CMD` are concatentated to construct ACI's `Exec` field.
+This means after the conversion, we are not able to replace only `ENTRYPOINT` or `CMD` without touching the other part.
+So for now, users are recommended to specify the **executable path** in `Command` and **arguments** in `Args`.
+(This has the same effect if users specify the **executable path + arguments** in `Command` or `Args` alone).
+
+For example:
+
+```yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: nginx
+  labels:
+    name: nginx
+spec:
+  containers:
+  - name: nginx
+    image: nginx
+    ports:
+    - containerPort: 80
+```
+
+The above pod yaml file is valid as it's not specifying `Command` or `Args`, so the default `ENTRYPOINT` and `CMD` of the image will be used.
+
+```yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: busybox
+  labels:
+    name: busybox
+spec:
+  containers:
+  - name: busybox
+    image: busybox
+    command:
+    - /bin/sleep
+    - 1000
+```
+
+```yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: busybox
+  labels:
+    name: busybox
+spec:
+  containers:
+  - name: busybox
+    image: busybox
+    command:
+    - /bin/sleep
+    args:
+    - 1000
+```
+
+```yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: busybox
+  labels:
+    name: busybox
+spec:
+  containers:
+  - name: busybox
+    image: busybox
+    args:
+    - /bin/sleep
+    - 1000
+```
+
+All the three examples above are valid as they contain both the executable path and the arguments.
+
+```yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: busybox
+  labels:
+    name: busybox
+spec:
+  containers:
+  - name: busybox
+    image: busybox
+    args:
+    - 1000
+```
+
+The last example is invalid, as we cannot override just the `CMD` of the image alone.