新增learn-kubernetes（https://github.com/yyong-brs/learn-kubernetes）相关文件

learn/learn-kubernetes-master/kiamol/ch12/lab/README.md

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+# Ch12 lab
+
+## Setup
+
+Deploy the namespaces & Services:
+
+```
+kubectl apply -f lab/namespaces.yaml -f lab/services.yaml
+```
+
+Find out how many cores your node has available:
+
+```
+kubectl get nodes -o jsonpath='{.items[].status.allocatable.cpu}'
+```
+
+> Quotas should allocate 50% for UAT, 25% for test and 25% for dev
+
+## Sample Solution
+
+My node has 8 CPU cores, so my [quotas.yaml](./solution/quotas.yaml) is set with 4 cores for UAT and 2 each for dev and test.
+
+Set the quotas:
+
+```
+kubectl apply -f lab/solution/quotas.yaml
+```
+
+My Pi app is set in [web.yaml](./solution/web.yaml) to use 0.5 cores, so I can run at least four replicas in every environment.
+
+Deploy to each namespace:
+
+```
+kubectl apply -f lab/solution/web.yaml -n pi-dev
+
+kubectl apply -f lab/solution/web.yaml -n pi-test
+
+kubectl apply -f lab/solution/web.yaml -n pi-uat
+```
+
+You should find all ReplicaSets are running at desired capacity:
+
+```
+kubectl get rs -l app=pi-web --all-namespaces
+```
+
+UAT has enough quota to run 8 replicas on my node:
+
+```
+kubectl scale deploy/pi-web --replicas 8 -n pi-uat
+```
+
+... except that it doesn't:
+
+```
+kubectl get rs -l app=pi-web -n pi-uat\
+
+# returns 6 Pods running out of 8 desired
+```
+
+> You can't use 100% of the node's CPU because Kubernetes system components allocate CPU themselves.
+
+## Teardown
+
+Remove the namespaces and that removes everything:
+
+```
+kubectl delete ns -l kiamol=ch12-lab
+```