Add documentation for crictl (#8880)

* Add documentation for crictl * Copyedit Signed-off-by: Misty Stanley-Jones <[email protected]> * Final copyedit
kubernetes · Jun 27, 2018 · d6b0282 · d6b0282
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diff --git a/content/en/docs/tasks/debug-application-cluster/crictl.md b/content/en/docs/tasks/debug-application-cluster/crictl.md
@@ -0,0 +1,326 @@
+---
+reviewers:
+- Random-Liu
+- feiskyer
+- mrunalp
+title: Debugging Kubernetes nodes with crictl
+content_template: templates/task
+---
+
+{{< toc >}}
+
+{{% capture overview %}}
+
+{{< feature-state for_k8s_version="v1.11" state="stable" >}}
+
+`crictl` is a command-line interface for CRI-compatible container runtimes.
+You can use it to inspect and debug container runtimes and applications on a
+Kubernetes node. `crictl` and its source are hosted in the
+[cri-tools](https://github.com/kubernetes-incubator/cri-tools) repository.
+
+{{% /capture %}}
+
+{{% capture prerequisites %}}
+
+`crictl` requires a Linux operating system with a CRI runtime.
+
+{{% /capture %}}
+
+{{% capture steps %}}
+
+## Installing crictl
+
+You can download a compressed archive `crictl` from the cri-tools [release
+page](https://github.com/kubernetes-incubator/cri-tools/releases), for several
+different architectures. Download the version that corresponds to your version
+of Kubernetes. Extract it and move it to a location on your system path, such as
+`/usr/local/bin/`.
+
+## General usage
+
+The `crictl` command has several subcommands and runtime flags. Use
+`crictl help` or `crictl <subcommand> help` for more details.
+
+`crictl` connects to `unix:///var/run/dockershim.sock` by default. For other
+runtimes, you can set the endpoint in multiple different ways:
+
+- By setting flags `--runtime-endpoint` and `--image-endpoint`
+- By setting environment variables `CONTAINER_RUNTIME_ENDPOINT` and `IMAGE_SERVICE_ENDPOINT`
+- By setting the endpoint in the config file `--config=/etc/crictl.yaml`
+
+You can also specify timeout values when connecting to the server and enable or
+disable debugging, by specifying `timeout` or `debug` values in the configuration
+file or using the `--timeout` and `--debug` command-line flags.
+
+To view or edit the current configuration, view or edit the contents of
+`/etc/crictl.yaml`.
+
+```sh
+$ cat /etc/crictl.yaml
+runtime-endpoint: unix:///var/run/dockershim.sock
+image-endpoint: unix:///var/run/dockershim.sock
+timeout: 10
+debug: true
+```
+
+## Example crictl commands
+
+The following examples show some `crictl` commands and and example output.
+
+{{< warning >}}
+If you use `crictl` to create pod sandboxes or containers on a running
+Kubernetes cluster, the Kubelet will eventually delete them. `crictl` is not a
+general purpose workflow tool, but a tool that is useful for debugging.
+{{< /warning >}}
+
+### List pods
+
+List all pods:
+
+```bash
+crictl pods
+```
+```none
+POD ID              CREATED              STATE               NAME                         NAMESPACE           ATTEMPT
+926f1b5a1d33a       About a minute ago   Ready               sh-84d7dcf559-4r2gq          default             0
+4dccb216c4adb       About a minute ago   Ready               nginx-65899c769f-wv2gp       default             0
+a86316e96fa89       17 hours ago         Ready               kube-proxy-gblk4             kube-system         0
+919630b8f81f1       17 hours ago         Ready               nvidia-device-plugin-zgbbv   kube-system         0
+```
+
+List pods by name:
+
+```bash
+crictl pods --name nginx-65899c769f-wv2gp
+```
+```none
+POD ID              CREATED             STATE               NAME                     NAMESPACE           ATTEMPT
+4dccb216c4adb       2 minutes ago       Ready               nginx-65899c769f-wv2gp   default             0
+```
+
+List pods by label:
+
+```bash
+crictl pods --label run=nginx
+```
+```none
+POD ID              CREATED             STATE               NAME                     NAMESPACE           ATTEMPT
+4dccb216c4adb       2 minutes ago       Ready               nginx-65899c769f-wv2gp   default             0
+```
+
+### List images
+
+List all images:
+
+```bash
+crictl images
+```
+```none
+IMAGE                                     TAG                 IMAGE ID            SIZE
+busybox                                   latest              8c811b4aec35f       1.15MB
+k8s-gcrio.azureedge.net/hyperkube-amd64   v1.10.3             e179bbfe5d238       665MB
+k8s-gcrio.azureedge.net/pause-amd64       3.1                 da86e6ba6ca19       742kB
+nginx                                     latest              cd5239a0906a6       109MB
+```
+
+List images by repository:
+
+```bash
+crictl images nginx
+```
+```none
+IMAGE               TAG                 IMAGE ID            SIZE
+nginx               latest              cd5239a0906a6       109MB
+```
+
+Only list image IDs:
+
+```bash
+crictl images -q
+```
+```none
+sha256:8c811b4aec35f259572d0f79207bc0678df4c736eeec50bc9fec37ed936a472a
+sha256:e179bbfe5d238de6069f3b03fccbecc3fb4f2019af741bfff1233c4d7b2970c5
+sha256:da86e6ba6ca197bf6bc5e9d900febd906b133eaa4750e6bed647b0fbe50ed43e
+sha256:cd5239a0906a6ccf0562354852fae04bc5b52d72a2aff9a871ddb6bd57553569
+```
+
+### List containers
+
+List all containers:
+
+```bash
+crictl ps -a
+```
+```none
+CONTAINER ID        IMAGE                                                                                                             CREATED             STATE               NAME                       ATTEMPT
+1f73f2d81bf98       busybox@sha256:141c253bc4c3fd0a201d32dc1f493bcf3fff003b6df416dea4f41046e0f37d47                                   7 minutes ago       Running             sh                         1
+9c5951df22c78       busybox@sha256:141c253bc4c3fd0a201d32dc1f493bcf3fff003b6df416dea4f41046e0f37d47                                   8 minutes ago       Exited              sh                         0
+87d3992f84f74       nginx@sha256:d0a8828cccb73397acb0073bf34f4d7d8aa315263f1e7806bf8c55d8ac139d5f                                     8 minutes ago       Running             nginx                      0
+1941fb4da154f       k8s-gcrio.azureedge.net/hyperkube-amd64@sha256:00d814b1f7763f4ab5be80c58e98140dfc69df107f253d7fdd714b30a714260a   18 hours ago        Running             kube-proxy                 0
+```
+
+List running containers:
+
+```bash
+crictl ps
+```
+```none
+CONTAINER ID        IMAGE                                                                                                             CREATED             STATE               NAME                       ATTEMPT
+1f73f2d81bf98       busybox@sha256:141c253bc4c3fd0a201d32dc1f493bcf3fff003b6df416dea4f41046e0f37d47                                   6 minutes ago       Running             sh                         1
+87d3992f84f74       nginx@sha256:d0a8828cccb73397acb0073bf34f4d7d8aa315263f1e7806bf8c55d8ac139d5f                                     7 minutes ago       Running             nginx                      0
+1941fb4da154f       k8s-gcrio.azureedge.net/hyperkube-amd64@sha256:00d814b1f7763f4ab5be80c58e98140dfc69df107f253d7fdd714b30a714260a   17 hours ago        Running             kube-proxy                 0
+```
+
+### Execute a command in a running container
+
+```bash
+crictl exec -i -t 1f73f2d81bf98 ls
+```
+```none
+bin   dev   etc   home  proc  root  sys   tmp   usr   var
+```
+
+### Get a coontainer's logs
+
+Get all container logs:
+
+```bash
+crictl logs 87d3992f84f74
+```
+```none
+10.240.0.96 - - [06/Jun/2018:02:45:49 +0000] "GET / HTTP/1.1" 200 612 "-" "curl/7.47.0" "-"
+10.240.0.96 - - [06/Jun/2018:02:45:50 +0000] "GET / HTTP/1.1" 200 612 "-" "curl/7.47.0" "-"
+10.240.0.96 - - [06/Jun/2018:02:45:51 +0000] "GET / HTTP/1.1" 200 612 "-" "curl/7.47.0" "-"
+```
+
+Get only the latest `N` lines of logs:
+
+```bash
+crictl logs --tail=1 87d3992f84f74
+```
+```none
+10.240.0.96 - - [06/Jun/2018:02:45:51 +0000] "GET / HTTP/1.1" 200 612 "-" "curl/7.47.0" "-"
+```
+
+### Run a pod sandbox
+
+Using `crictl` to run a pod sandbox is useful for debugging container runtimes.
+On a running Kubernetes cluster, the sandbox will eventually be stopped and
+deleted by the Kubelet.
+
+1.  Create a JSON file like the following:
+
+      ```json
+      {
+          "metadata": {
+              "name": "nginx-sandbox",
+              "namespace": "default",
+              "attempt": 1,
+              "uid": "hdishd83djaidwnduwk28bcsb"
+          },
+          "logDirectory": "/tmp",
+          "linux": {
+          }
+      }
+      ```
+
+2.  Use the `crictl runp` command to apply the JSON and run the sandbox.
+
+      ```bash
+      crictl runp pod-config.json
+      ```
+
+      The ID of the sandbox is returned.
+
+### Create a container
+
+Using `crictl` to create a container is useful for debugging container runtimes.
+On a running Kubernetes cluster, the sandbox will eventually be stopped and
+deleted by the Kubelet.
+
+1.  Pull a busybox image
+
+      ```bash
+      crictl pull busybox
+      Image is up to date for busybox@sha256:141c253bc4c3fd0a201d32dc1f493bcf3fff003b6df416dea4f41046e0f37d47
+      ```
+
+2.  Create configs for the pod and the container:
+
+      **Pod config**:
+      ```yaml
+      {
+          "metadata": {
+              "name": "nginx-sandbox",
+              "namespace": "default",
+              "attempt": 1,
+              "uid": "hdishd83djaidwnduwk28bcsb"
+          },
+          "log_directory": "/tmp",
+          "linux": {
+          }
+      }
+      ```
+
+      **Container config**:
+      ```yaml
+      {
+        "metadata": {
+            "name": "busybox"
+        },
+        "image":{
+            "image": "busybox"
+        },
+        "command": [
+            "top"
+        ],
+        "log_path":"busybox/0.log",
+        "linux": {
+        }
+      }
+      ```
+
+3.  Create the container, passing the ID of the previously-created pod, the
+    container config file, and the pod config file. The ID of the container is
+    returned.
+
+      ```bash
+      crictl create f84dd361f8dc51518ed291fbadd6db537b0496536c1d2d6c05ff943ce8c9a54f container-config.json pod-config.json
+      ```
+
+4.  List all containers and verify that the newly-created container has its
+    state set to `Created`.
+
+      ```bash
+      crictl ps -a
+      ```
+      ```none
+      CONTAINER ID        IMAGE               CREATED             STATE               NAME                ATTEMPT
+      3e025dd50a72d       busybox             32 seconds ago      Created             busybox             0
+      ```
+
+### Start a container
+
+To start a container, pass its ID to `crictl start`:
+
+```bash
+crictl start 3e025dd50a72d956c4f14881fbb5b1080c9275674e95fb67f965f6478a957d60
+```
+```none
+3e025dd50a72d956c4f14881fbb5b1080c9275674e95fb67f965f6478a957d60
+
+$ crictl ps
+CONTAINER ID        IMAGE               CREATED              STATE               NAME                ATTEMPT
+3e025dd50a72d       busybox             About a minute ago   Running             busybox             0
+```
+
+{{% /capture %}}
+
+
+{{% capture discussion %}}
+
+See [kubernetes-incubator/cri-tools](https://github.com/kubernetes-incubator/cri-tools)
+for more information.
+
+{{% /capture %}}
diff --git a/content/en/docs/tasks/debug-application-cluster/debug-application-introspection.md b/content/en/docs/tasks/debug-application-cluster/debug-application-introspection.md
@@ -363,6 +363,8 @@ status:
     systemUUID: ABE5F6B4-D44B-108B-C46A-24CCE16C8B6E
 ```
 
+{{% /capture %}}
+
 {{% capture whatsnext %}}
 
 Learn about additional debugging tools, including:
@@ -372,5 +374,6 @@ Learn about additional debugging tools, including:
 * [Getting into containers via `exec`](/docs/tasks/debug-application-cluster/get-shell-running-container/)
 * [Connecting to containers via proxies](/docs/tasks/access-kubernetes-api/http-proxy-access-api/)
 * [Connecting to containers via port forwarding](/docs/tasks/access-application-cluster/port-forward-access-application-cluster/)
+* [Inspect Kubernetes node with crictl](/docs/tasks/debug-application-cluster/crictl/)
 
 {{% /capture %}}