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docs/kube-runtime/kube-runtime.md

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+# Kube-runtime
+
+## Goal
+[kube-runtime](https://github.com/microsoft/openpai-runtime) is a module that provides runtime support for job containers. For more detail, please refer to [openpai-runtime](https://github.com/microsoft/openpai-runtime).
+
+## Build
+If you want to build [kube-runtime](https://github.com/microsoft/openpai-runtime) only, under the `build` directory, run the following command, note to replace `/path/to/cluster-configuration/dir` with your own cluster configuration path.
+
+```sh
+python pai_build.py -p /path/to/cluster-configuration/dir -n kube-runtime
+```
+
+## Deployment
+
+The deployment of kube-runtime goes with the bootstrapping process of the whole PAI cluster, which is described in detail in [Tutorial: Booting up the cluster](../pai-management/doc/distributed-deploy.md).
+
+If you want to redeploy kube-runtime only, you can run following commands, note to replace `/path/to/cluster-configuration/dir` with your own cluster configuration path:
+
+```sh
+python paictl.py service start -p /path/to/cluster-configuration/dir -n kube-runtime
+```
+For more details, please refer to [Maintain your service](../paictl/paictl-manual.md#Service).
+
+
+## Reference
+
+- [openpai-runtime](https://github.com/microsoft/openpai-runtime)