update readme for notes

Signed-off-by: honglei <shenhongleigood@163.com>

README.md

@@ -52,10 +52,11 @@ There are three scenarios to use KubeKey.
   * `sudo`/`curl`/`openssl` should be used in all nodes.
   * `ebtables`/`socat`/`ipset`/`conntrack` should be installed in all nodes.
   * `docker` can be installed by yourself or by KubeKey.
-
+  * `Red Hat` includes `SELinux` in its `Linux release`. It is recommended to close SELinux or [switch the mode of SELinux](./docs/turn-off-SELinux.md) to `Permissive`
 > * It's recommended that Your OS is clean (without any other software installed), otherwise there may be conflicts.  
 > * A container image mirror (accelerator) is recommended to be prepared if you have trouble downloading images from dockerhub.io. [Configure registry-mirrors for the Docker daemon](https://docs.docker.com/registry/recipes/mirror/#configure-the-docker-daemon).
 > * KubeKey will install [OpenEBS](https://openebs.io/) to provision LocalPV for development and testing environment by default, this is convenient for new users. For production, please use NFS / Ceph / GlusterFS  or commercial products as persistent storage, and install the [relevant client](docs/storage-client.md) in all nodes.
+> * If you encounter `Permission denied` when copying, it is recommended to check [SELinux and turn off it](./docs/turn-off-SELinux.md) first 
 
 * Networking and DNS requirements:
   * Make sure the DNS address in `/etc/resolv.conf` is available. Otherwise, it may cause some issues of DNS in cluster.

README_zh-CN.md

@@ -52,10 +52,12 @@
   * `sudo`/`curl`/`openssl` 应在所有节点使用。
   * `ebtables`/`socat`/`ipset`/`conntrack` 应安装在所有节点。
   * `docker` 可以自己安装，也可以通过 KubeKey 安装。
+  * `Red Hat` 在其 `Linux` 发行版本中包括了`SELinux`，建议[关闭SELinux](./docs/turn-off-SELinux_zh-CN.md)或者将[SELinux的模式切换](./docs/turn-off-SELinux_zh-CN.md)为Permissive[宽容]工作模式
 
 > * 建议您的操作系统环境足够干净 (不安装任何其他软件)，否则可能会发生冲突。
 > * 如果在从 dockerhub.io 下载镜像时遇到问题，建议准备一个容器镜像仓库 (加速器)。[为 Docker 守护程序配置镜像加速](https://docs.docker.com/registry/recipes/mirror/#configure-the-docker-daemon)。
 > * 默认情况下，KubeKey 将安装 [OpenEBS](https://openebs.io/) 来为开发和测试环境配置 LocalPV，这对新用户来说非常方便。对于生产，请使用 NFS/Ceph/GlusterFS 或商业化存储作为持久化存储，并在所有节点中安装[相关的客户端](./docs/storage-client.md) 。
+> * 如果遇到拷贝时报权限问题Permission denied,建议优先考虑查看[SELinux的原因](./docs/turn-off-SELinux_zh-CN.md)。
 
 * 网络和 DNS 要求：
   * 确保 `/etc/resolv.conf` 中的 DNS 地址可用。否则，可能会导致群集中出现某些 DNS 问题。

docs/turn-off-SELinux.md

@@ -0,0 +1,21 @@
+# How to turn off SELinux
+## turn off SELinux
+```shell script
+# Edit the configuration
+sed -i ‘s/SELINUX=enforcing/SELINUX=disabled/g’ /etc/selinux/config
+#restart the system  
+reboot
+# check SELinux
+getenforce
+```
+> Edit the configuration file /etc/selinux/config, change SELINUX= to SELINUX=disabled, then restart the system, SELinux will be disabled
+
+## Temporarily shut down SELinux
+```shell script
+# Temporarily closing SELinux is to switch between enforcing and permissive modes
+setenforce 0 #Switch to tolerance mode
+setenforce 1 #Switch to mandatory mode
+# check SELinux
+getenforce
+```
+> Temporary shutdown enforcing, invalid after restarting the system

docs/turn-off-SELinux_zh-CN.md

@@ -0,0 +1,21 @@
+# 如何关闭SELinux
+## 永久关闭SELinux
+```shell script
+# 永久关闭SELinux
+sed -i ‘s/SELINUX=enforcing/SELINUX=disabled/g’ /etc/selinux/config
+#关闭后需要重启系统
+reboot
+# 查看SELinux的状态
+getenforce
+```
+> 编辑配置文件/etc/selinux/config，把 SELINUX= 更改为 SELINUX=disabled ，然后重启系统，SELinux 就被禁用了
+
+## 临时关闭SELinux
+```shell script
+# 临时关闭SELinux就是enforcing 和 permissive 两种模式之间进行切换
+setenforce 0 #切换成宽容模式
+setenforce 1 #切换成强制模式
+# check SELinux
+getenforce
+```
+> 临时切换工作模式，重启系统生失效