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Code Issues Projects Releases Wiki Activity

remove command prompts and separate commands from output (#11848)

pull/11868/head
makocchi 2018-12-23 10:18:36 +09:00 committed by Kubernetes Prow Robot
parent a52dfece47
commit 950bcbef2b
1 changed files with 37 additions and 10 deletions
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47
content/en/docs/tasks/debug-application-cluster/debug-application-introspection.md
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@ -26,12 +26,20 @@ For this example we'll use a Deployment to create two pods, similar to the earli
Create deployment by running following command:
```shell
$ kubectl create -f https://k8s.io/examples/application/nginx-with-request.yaml
kubectl create -f https://k8s.io/examples/application/nginx-with-request.yaml
```
```none
deployment.apps/nginx-deployment created
```
Check pod status by following command:
```shell
$ kubectl get pods
kubectl get pods
```
```none
NAME READY STATUS RESTARTS AGE
nginx-deployment-1006230814-6winp 1/1 Running 0 11s
nginx-deployment-1006230814-fmgu3 1/1 Running 0 11s
@ -40,13 +48,16 @@ nginx-deployment-1006230814-fmgu3 1/1 Running 0 11s
We can retrieve a lot more information about each of these pods using `kubectl describe pod`. For example:
```shell
$ kubectl describe pod nginx-deployment-1006230814-6winp
kubectl describe pod nginx-deployment-1006230814-6winp
```
```none
Name: nginx-deployment-1006230814-6winp
Namespace: default
Node: kubernetes-node-wul5/10.240.0.9
Start Time: Thu, 24 Mar 2016 01:39:49 +0000
Labels: app=nginx,pod-template-hash=1006230814
Annotations: kubernetes.io/created-by={"kind":"SerializedReference","apiVersion":"v1","reference":{"kind" :"ReplicaSet","namespace":"default","name":"nginx-deployment-1956810328","uid":"14e607e7-8ba1-11e7-b5cb-fa16" ...
Annotations: kubernetes.io/created-by={"kind":"SerializedReference","apiVersion":"v1","reference":{"kind":"ReplicaSet","namespace":"default","name":"nginx-deployment-1956810328","uid":"14e607e7-8ba1-11e7-b5cb-fa16" ...
Status: Running
IP: 10.244.0.6
Controllers: ReplicaSet/nginx-deployment-1006230814
@ -112,7 +123,10 @@ Lastly, you see a log of recent events related to your Pod. The system compresse
A common scenario that you can detect using events is when you've created a Pod that won't fit on any node. For example, the Pod might request more resources than are free on any node, or it might specify a label selector that doesn't match any nodes. Let's say we created the previous Deployment with 5 replicas (instead of 2) and requesting 600 millicores instead of 500, on a four-node cluster where each (virtual) machine has 1 CPU. In that case one of the Pods will not be able to schedule. (Note that because of the cluster addon pods such as fluentd, skydns, etc., that run on each node, if we requested 1000 millicores then none of the Pods would be able to schedule.)
```shell
$ kubectl get pods
kubectl get pods
```
```none
NAME READY STATUS RESTARTS AGE
nginx-deployment-1006230814-6winp 1/1 Running 0 7m
nginx-deployment-1006230814-fmgu3 1/1 Running 0 7m
@ -124,7 +138,10 @@ nginx-deployment-1370807587-fz9sd 0/1 Pending 0 1m
To find out why the nginx-deployment-1370807587-fz9sd pod is not running, we can use `kubectl describe pod` on the pending Pod and look at its events:
```shell
$ kubectl describe pod nginx-deployment-1370807587-fz9sd
kubectl describe pod nginx-deployment-1370807587-fz9sd
```
```none
Name: nginx-deployment-1370807587-fz9sd
Namespace: default
Node: /
@ -178,8 +195,11 @@ To see events from all namespaces, you can use the `--all-namespaces` argument.
In addition to `kubectl describe pod`, another way to get extra information about a pod (beyond what is provided by `kubectl get pod`) is to pass the `-o yaml` output format flag to `kubectl get pod`. This will give you, in YAML format, even more information than `kubectl describe pod`--essentially all of the information the system has about the Pod. Here you will see things like annotations (which are key-value metadata without the label restrictions, that is used internally by Kubernetes system components), restart policy, ports, and volumes.
```shell
kubectl get pod nginx-deployment-1006230814-6winp -o yaml
```
```yaml
$ kubectl get pod nginx-deployment-1006230814-6winp -o yaml
apiVersion: v1
kind: Pod
metadata:
@ -255,7 +275,10 @@ status:
Sometimes when debugging it can be useful to look at the status of a node -- for example, because you've noticed strange behavior of a Pod that's running on the node, or to find out why a Pod won't schedule onto the node. As with Pods, you can use `kubectl describe node` and `kubectl get node -o yaml` to retrieve detailed information about nodes. For example, here's what you'll see if a node is down (disconnected from the network, or kubelet dies and won't restart, etc.). Notice the events that show the node is NotReady, and also notice that the pods are no longer running (they are evicted after five minutes of NotReady status).
```shell
$ kubectl get nodes
kubectl get nodes
```
```none
NAME STATUS ROLES AGE VERSION
kubernetes-node-861h NotReady <none> 1h v1.13.0
kubernetes-node-bols Ready <none> 1h v1.13.0
@ -264,7 +287,10 @@ kubernetes-node-unaj Ready <none> 1h v1.13.0
```
```shell
$ kubectl describe node kubernetes-node-861h
kubectl describe node kubernetes-node-861h
```
```none
Name: kubernetes-node-861h
Role
Labels: beta.kubernetes.io/arch=amd64
@ -318,8 +344,9 @@ Events: <none>
```
```shell
$ kubectl get node kubernetes-node-861h -o yaml
kubectl get node kubernetes-node-861h -o yaml
```
```yaml
apiVersion: v1
kind: Node