2019独角兽企业重金招聘Python工程师标准>>> 
一、搭建RKE集群
1.1 概述
REK是Rancher Kubernetes Engine，通过rke工具可以快速简单地搭建一套 Kubernetes集群。
搭建的重点在于环境，如果环境配置正确，一切都会很顺利。
1.2 环境准备
首先说明下依赖版本：
| 序号 | 名称 | 版本 | 备注 |
| 1 | ubuntu | 16.04.1 | |
| 2 | docker | 17.03.2-ce | |
| 3 | rke | 0.1.1 | |
| 4 | k8s | 1.8.7 | |
| 5 | rancher | 2.0.0-alpha16 |
然后开始准备环境，注意需要两台机器，一台用于安装rke集群，一台用于rke工具控制机。注意控制机最好和rke集群执行同样的环境准备，否则有可能出现莫名安装不上的问题。
1、初装的ubuntu自带的编辑命令不太好用，这里卸载原来的，然后安装vi
#此时未使用root登陆，需要增加sudo，以获取root权限
#首先卸载旧版本的vi编辑器：
sudo apt-get remove vim-common
#然后安装新版vi即可：
$sudo apt-get install vim
2、ubuntu默认不允许使用root登陆，为了减少不必要的麻烦，这里修改配置启用root，然后以后所有步骤都在root用户下操作。
#1、将PermitRootLogin prohibit-password修改为PermitRootLogin yes
#2、取消注释AuthorizedKeysFile %h/.ssh/authorized_keys
sudo vi /etc/ssh/sshd_config
#3、切换到root登陆
sudo su
#4、设置root密码
sudo passwd root
#5、更新密码
sudo passwd -u root
#6、重启ssh
sudo service ssh restart
修改完后，使用root登陆，重新打开客户端。
3、修改主机名，注意不能包含大写字母，并且最好不要包含特殊字符,修改完后重启机器。
vi /etc/hostname 4、确保hosts文件包含如下行
127.0.0.1 localhost另外ubuntu会把主机名对应127.0.0.1加入到hosts里，第三步我们改了名称，所以hosts也要相应改变，但注意IP要改为真实IP
172.16.10.99 worker025、启用cgroup内存和Swap限额，修改/etc/default/grub 配置文件，修改/增加两项
GRUB_CMDLINE_LINUX_DEFAULT="cgroup_enable=memory swapaccount=1"
GRUB_CMDLINE_LINUX="cgroup_enable=memory swapaccount=1"修改完后执行
update-grub执行完后，再次重启机器。
6、永久禁用交换分区，直接修改/etc/fstab文件，注释掉swap项
# swap was on /dev/sda6 during installation
#UUID=5e4b0d14-ad10-4d24-8f7c-4a07c4eb4d29 none swap sw 0 07、其他的检查防火墙（默认无规则）、SELinux（默认未启用）、ipv4转发（默认已启用）、配置rke控制机到rke集群机器的单向免密登陆
8、下载安装docker17.03.2-ce版本（https://docs.docker.com/install/linux/docker-ce/ubuntu/#upgrade-docker-ce），最好再设置加速器，不然下载镜像会很慢。最后将root再添加到docker用户组中。
1.3安装rke
rke的github地址是https://github.com/rancher/rke，点击到releases页面，下载rke工具。下载成功后，无需其他操作，只需要赋权即可使用。
chmod 777 rke
#验证安装
./rke -version1.4部署rke集群
1、重启一下机器（为什么重启？不知道，偶发装不上，重启就好了，这里为了确保成功，先重启下。）
2、创建cluster.yml文件，内容类似如下：
nodes:
- address: 172.16.10.99
user: root
role: [controlplane,worker,etcd]
services:
etcd:
image: quay.io/coreos/etcd:latest
kube-api:
image: rancher/k8s:v1.8.3-rancher2
kube-controller:
image: rancher/k8s:v1.8.3-rancher2
scheduler:
image: rancher/k8s:v1.8.3-rancher2
kubelet:
image: rancher/k8s:v1.8.3-rancher2
kubeproxy:
image: rancher/k8s:v1.8.3-rancher2注意etcd的那个镜像，不要更换其他etcd镜像，更换会导致启动403错误。quay.io的镜像比较慢，可以先pull下来，但绝对不能换。
3、执行
./rke up --config cluster.yml执行结果如下：
root@master:/opt/rke# ./rke up --config cluster-99.yml
INFO[0000] Building Kubernetes cluster
INFO[0000] [dialer] Setup tunnel for host [172.16.10.99]
INFO[0000] [network] Deploying port listener containers
INFO[0001] [network] Successfully started [rke-etcd-port-listener] container on host [172.16.10.99]
INFO[0001] [network] Successfully started [rke-cp-port-listener] container on host [172.16.10.99]
INFO[0002] [network] Successfully started [rke-worker-port-listener] container on host [172.16.10.99]
INFO[0002] [network] Port listener containers deployed successfully
INFO[0002] [network] Running all -> etcd port checks
INFO[0003] [network] Successfully started [rke-port-checker] container on host [172.16.10.99]
INFO[0004] [network] Successfully started [rke-port-checker] container on host [172.16.10.99]
INFO[0004] [network] Running control plane -> etcd port checks
INFO[0005] [network] Successfully started [rke-port-checker] container on host [172.16.10.99]
INFO[0005] [network] Running workers -> control plane port checks
INFO[0005] [network] Successfully started [rke-port-checker] container on host [172.16.10.99]
INFO[0006] [network] Checking KubeAPI port Control Plane hosts
INFO[0006] [network] Removing port listener containers
INFO[0006] [remove/rke-etcd-port-listener] Successfully removed container on host [172.16.10.99]
INFO[0007] [remove/rke-cp-port-listener] Successfully removed container on host [172.16.10.99]
INFO[0007] [remove/rke-worker-port-listener] Successfully removed container on host [172.16.10.99]
INFO[0007] [network] Port listener containers removed successfully
INFO[0007] [certificates] Attempting to recover certificates from backup on host [172.16.10.99]
INFO[0007] [certificates] No Certificate backup found on host [172.16.10.99]
INFO[0007] [certificates] Generating kubernetes certificates
INFO[0007] [certificates] Generating CA kubernetes certificates
INFO[0008] [certificates] Generating Kubernetes API server certificates
INFO[0008] [certificates] Generating Kube Controller certificates
INFO[0009] [certificates] Generating Kube Scheduler certificates
INFO[0011] [certificates] Generating Kube Proxy certificates
INFO[0011] [certificates] Generating Node certificate
INFO[0012] [certificates] Generating admin certificates and kubeconfig
INFO[0012] [certificates] Generating etcd-172.16.10.99 certificate and key
INFO[0013] [certificates] Temporarily saving certs to etcd host [172.16.10.99]
INFO[0018] [certificates] Saved certs to etcd host [172.16.10.99]
INFO[0018] [reconcile] Reconciling cluster state
INFO[0018] [reconcile] This is newly generated cluster
INFO[0018] [certificates] Deploying kubernetes certificates to Cluster nodes
INFO[0024] Successfully Deployed local admin kubeconfig at [./kube_config_cluster-99.yml]
INFO[0024] [certificates] Successfully deployed kubernetes certificates to Cluster nodes
INFO[0024] Pre-pulling kubernetes images
INFO[0024] Kubernetes images pulled successfully
INFO[0024] [etcd] Building up Etcd Plane..
INFO[0025] [etcd] Successfully started [etcd] container on host [172.16.10.99]
INFO[0025] [etcd] Successfully started Etcd Plane..
INFO[0025] [controlplane] Building up Controller Plane..
INFO[0026] [controlplane] Successfully started [kube-api] container on host [172.16.10.99]
INFO[0026] [healthcheck] Start Healthcheck on service [kube-api] on host [172.16.10.99]
INFO[0036] [healthcheck] service [kube-api] on host [172.16.10.99] is healthy
INFO[0037] [controlplane] Successfully started [kube-controller] container on host [172.16.10.99]
INFO[0037] [healthcheck] Start Healthcheck on service [kube-controller] on host [172.16.10.99]
INFO[0037] [healthcheck] service [kube-controller] on host [172.16.10.99] is healthy
INFO[0038] [controlplane] Successfully started [scheduler] container on host [172.16.10.99]
INFO[0038] [healthcheck] Start Healthcheck on service [scheduler] on host [172.16.10.99]
INFO[0038] [healthcheck] service [scheduler] on host [172.16.10.99] is healthy
INFO[0038] [controlplane] Successfully started Controller Plane..
INFO[0038] [authz] Creating rke-job-deployer ServiceAccount
INFO[0038] [authz] rke-job-deployer ServiceAccount created successfully
INFO[0038] [authz] Creating system:node ClusterRoleBinding
INFO[0038] [authz] system:node ClusterRoleBinding created successfully
INFO[0038] [certificates] Save kubernetes certificates as secrets
INFO[0039] [certificates] Successfully saved certificates as kubernetes secret [k8s-certs]
INFO[0039] [state] Saving cluster state to Kubernetes
INFO[0039] [state] Successfully Saved cluster state to Kubernetes ConfigMap: cluster-state
INFO[0039] [worker] Building up Worker Plane..
INFO[0039] [sidekick] Sidekick container already created on host [172.16.10.99]
INFO[0040] [worker] Successfully started [kubelet] container on host [172.16.10.99]
INFO[0040] [healthcheck] Start Healthcheck on service [kubelet] on host [172.16.10.99]
INFO[0046] [healthcheck] service [kubelet] on host [172.16.10.99] is healthy
INFO[0046] [worker] Successfully started [kube-proxy] container on host [172.16.10.99]
INFO[0046] [healthcheck] Start Healthcheck on service [kube-proxy] on host [172.16.10.99]
INFO[0052] [healthcheck] service [kube-proxy] on host [172.16.10.99] is healthy
INFO[0052] [sidekick] Sidekick container already created on host [172.16.10.99]
INFO[0052] [healthcheck] Start Healthcheck on service [kubelet] on host [172.16.10.99]
INFO[0052] [healthcheck] service [kubelet] on host [172.16.10.99] is healthy
INFO[0052] [healthcheck] Start Healthcheck on service [kube-proxy] on host [172.16.10.99]
INFO[0052] [healthcheck] service [kube-proxy] on host [172.16.10.99] is healthy
INFO[0052] [sidekick] Sidekick container already created on host [172.16.10.99]
INFO[0052] [healthcheck] Start Healthcheck on service [kubelet] on host [172.16.10.99]
INFO[0052] [healthcheck] service [kubelet] on host [172.16.10.99] is healthy
INFO[0052] [healthcheck] Start Healthcheck on service [kube-proxy] on host [172.16.10.99]
INFO[0052] [healthcheck] service [kube-proxy] on host [172.16.10.99] is healthy
INFO[0052] [worker] Successfully started Worker Plane..
INFO[0052] [network] Setting up network plugin: flannel
INFO[0052] [addons] Saving addon ConfigMap to Kubernetes
INFO[0053] [addons] Successfully Saved addon to Kubernetes ConfigMap: rke-network-plugin
INFO[0053] [addons] Executing deploy job..
INFO[0058] [sync] Syncing nodes Labels and Taints
INFO[0058] [sync] Successfully synced nodes Labels and Taints
INFO[0058] [addons] Setting up KubeDNS
INFO[0058] [addons] Saving addon ConfigMap to Kubernetes
INFO[0058] [addons] Successfully Saved addon to Kubernetes ConfigMap: rke-kubedns-addon
INFO[0058] [addons] Executing deploy job..
INFO[0063] [addons] KubeDNS deployed successfully..
INFO[0063] [ingress] Setting up nginx ingress controller
INFO[0063] [addons] Saving addon ConfigMap to Kubernetes
INFO[0063] [addons] Successfully Saved addon to Kubernetes ConfigMap: rke-ingress-controller
INFO[0063] [addons] Executing deploy job..
INFO[0068] [ingress] ingress controller nginx is successfully deployed
INFO[0068] [addons] Setting up user addons..
INFO[0068] [addons] No user addons configured..
INFO[0068] Finished building Kubernetes cluster successfully 如果执行过程出现错误，可以先执行remove，再执行up，如果还不行，先remove再重启机器，最后在up。一般都会成功，如果执行了如上步骤还不行，再看具体报错信息。
二、导入rke到rancher2.0（预览版）
点击创建集群，在最右边有个导入现有集群。
执行rke命令的目录下会自动生成一个kube_config_cluster.yml文件，点击页面的导入，把该文件导入。
注意：rancher2.0，现在都是开发版，存在各种问题，仅适合调研用，缺少很多东西，不适合生产用。消息说三月底会推送2.0正式版。
三、附录
rke安装注意事项：http://blog.csdn.net/csdn_duomaomao/article/details/79325759
rancher导入rke：http://blog.csdn.net/csdn_duomaomao/article/details/79325436