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

learn/learn-kubernetes-master/kiamol/ch18/lab/README.md

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+# ch18 lab
+
+## Setup
+
+Connect to the control plane node:
+
+```
+vagrant ssh kiamol-control
+```
+
+## Sample Solution
+
+You take a node out of service by draining it, which reschedules the Pods - you need the DaemonSet flag so the system components are ignored:
+
+```
+kubectl drain kiamol-node --ignore-daemonsets
+```
+
+There is also the `kubectl cordon` command which marks the node so it won't have any new Pods scheduled, but that doesn't remove the existing Pods.
+
+When you're done working on the node you can bring it back into service by uncordoning it:
+
+```
+kubectl uncordon kiamol-node
+```
+
+That marks the node as available for work, but Kubernetes doesn't automatically reschedule existing workloads so the node won't start any application Pods. 
+
+You can rebalance the API Pods by restarting the rollout:
+
+```
+kubectl rollout restart deploy apod-api
+```
+
+## Teardown
+
+You can delete all of the Vagrant VMs with:
+
+```
+vagrant destroy
+```