通过 Kubeadm 安装 K8S 1.13.4与高可用

一、kuberadm 简介

Kuberadm 作用

Kubeadm 是一个工具，它提供了 kubeadm init 以及 kubeadm join 这两个命令作为快速创建 kubernetes 集群的最佳实践。

kubeadm 通过执行必要的操作来启动和运行一个最小可用的集群。它被故意设计为只关心启动集群，而不是之前的节点准备工作。同样的，诸如安装各种各样值得拥有的插件，例如 Kubernetes Dashboard、监控解决方案以及特定云提供商的插件，这些都不在它负责的范围。

相反，我们期望由一个基于 kubeadm 从更高层设计的更加合适的工具来做这些事情；并且，理想情况下，使用 kubeadm 作为所有部署的基础将会使得创建一个符合期望的集群变得容易。

Kuberadm 功能

• kubeadm init： 启动一个 Kubernetes 主节点
• kubeadm join： 启动一个 Kubernetes 工作节点并且将其加入到集群
• kubeadm upgrade： 更新一个 Kubernetes 集群到新版本
• kubeadm config： 如果使用 v1.7.x 或者更低版本的 kubeadm 初始化集群，您需要对集群做一些配置以便使用 kubeadm upgrade 命令
• kubeadm token： 管理 kubeadm join 使用的令牌
• kubeadm reset： 还原 kubeadm init 或者 kubeadm join 对主机所做的任何更改
• kubeadm version： 打印 kubeadm 版本
• kubeadm alpha： 预览一组可用的新功能以便从社区搜集反馈

功能版本

Area	Maturity Level
Command line UX	GA
Implementation	GA
Config file API	beta
CoreDNS	GA
kubeadm alpha subcommands	alpha
High availability	alpha
DynamicKubeletConfig	alpha
Self-hosting	alpha

二、前期准备

1、虚拟机分配说明

地址	主机名	内存&CPU	角色
192.168.2.10	—	—	vip
192.168.2.11	k8s-master-01	2C & 2G	master
192.168.2.12	k8s-master-02	2C & 2G	master
192.168.2.13	k8s-master-03	2C & 2G	master
192.168.2.21	k8s-node-01	2c & 4G	node
192.168.2.22	k8s-node-02	2c & 4G	node

2、各个节点端口占用

• Master 节点

规则	方向	端口范围	作用	使用者
TCP	Inbound	6443*	Kubernetes API	server All
TCP	Inbound	2379-2380	etcd server	client API kube-apiserver, etcd
TCP	Inbound	10250	Kubelet API	Self, Control plane
TCP	Inbound	10251	kube-scheduler	Self
TCP	Inbound	10252	kube-controller-manager	Sel

• node 节点

规则	方向	端口范围	作用	使用者
TCP	Inbound	10250	Kubelet API	Self, Control plane
TCP	Inbound	30000-32767	NodePort Services**	All

3、基础环境设置

Kubernetes 需要一定的环境来保证正常运行，如各个节点时间同步，主机名称解析，关闭防火墙等等。

主机名称解析

分布式系统环境中的多主机通信通常基于主机名称进行，这在 IP 地址存在变化的可能 性时为主机提供了固定的访问人口，因此一般需要有专用的 DNS 服务负责解决各节点主机 不过，考虑到此处部署的是测试集群，因此为了降低系复杂度，这里将基于 hosts 的文件进行主机名称解析。

修改hosts

分别进入不同服务器，进入 /etc/hosts 进行编辑

vim /etc/hosts

加入下面内容：

192.168.2.10    master.k8s.io      k8s-vip
192.168.2.11    master01.k8s.io    k8s-master-01
192.168.2.12    master02.k8s.io    k8s-master-02
192.168.2.13    master03.k8s.io    k8s-master-03
192.168.2.21    node01.k8s.io      k8s-node-01
192.168.2.22    node02.k8s.io      k8s-node-02

修改hostname

分别进入不同的服务器修改 hostname 名称

# 修改 192.168.2.11 服务器
hostnamectl  set-hostname  k8s-master-01
# 修改 192.168.2.12 服务器
hostnamectl  set-hostname  k8s-master-02
# 修改 192.168.2.13 服务器 hostnamectl set-hostname k8s-master-03 # 修改 192.168.2.21 服务器 hostnamectl set-hostname k8s-node-01 # 修改 192.168.2.22 服务器 hostnamectl set-hostname k8s-node-02 

主机时间同步

将各个服务器的时间同步，并设置开机启动同步时间服务

systemctl start chronyd.service
systemctl enable chronyd.service

关闭防火墙服务

停止并禁用防火墙

systemctl stop firewalld
systemctl disable firewalld

关闭并禁用SELinux

# 若当前启用了 SELinux 则需要临时设置其当前状态为 permissive
setenforce 0

# 编辑／etc/sysconfig selinux 文件，以彻底禁用 SELinux
sed -i 's/^SELINUX=enforcing$/SELINUX=disabled/' /etc/selinux/config

# 查看selinux状态
getenforce 

如果为permissive，则执行reboot重新启动即可

禁用 Swap 设备

kubeadm 默认会预先检当前主机是否禁用了 Swap 设备，并在未用时强制止部署 过程因此，在主机内存资惊充裕的条件下，需要禁用所有的 Swap 设备

# 关闭当前已启用的所有 Swap 设备
swapoff -a && sysctl -w vm.swappiness=0

# 编辑 fstab 配置文件，注释掉标识为 Swap 设备的所有行
vi /etc/fstab

设置系统参数

设置允许路由转发，不对bridge的数据进行处理

创建 /etc/sysctl.d/k8s.conf 文件

vim /etc/sysctl.d/k8s.conf

加入下面内容:

net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1

挂载br_netfilter

modprobe br_netfilter

生效配置文件

sysctl -p /etc/sysctl.d/k8s.conf

sysctl命令：用于运行时配置内核参数

查看是否生成相关文件

ls /proc/sys/net/bridge

资源配置文件

/etc/security/limits.conf 是 Linux 资源使用配置文件，用来限制用户对系统资源的使用

echo "* soft nofile 65536" >> /etc/security/limits.conf
echo "* hard nofile 65536" >> /etc/security/limits.conf
echo "* soft nproc 65536" >> /etc/security/limits.conf echo "* hard nproc 65536" >> /etc/security/limits.conf echo "* soft memlock unlimited" >> /etc/security/limits.conf echo "* hard memlock unlimited" >> /etc/security/limits.conf 

安装依赖包以及相关工具

yum install -y epel-release

yum install -y yum-utils device-mapper-persistent-data lvm2 net-tools conntrack-tools wget vim  ntpdate libseccomp libtool-ltdl

三、安装Keepalived

• keepalived介绍： 是集群管理中保证集群高可用的一个服务软件，其功能类似于heartbeat，用来防止单点故障
• Keepalived作用： 为haproxy提供vip（192.168.2.10）在三个haproxy实例之间提供主备，降低当其中一个haproxy失效的时对服务的影响。

1、yum安装Keepalived

# 安装keepalived
yum install -y keepalived

2、配置Keepalived

cat <<EOF > /etc/keepalived/keepalived.conf
! Configuration File for keepalived

# 主要是配置故障发生时的通知对象以及机器标识。
global_defs {
   # 标识本节点的字条串，通常为 hostname，但不一定非得是 hostname。故障发生时，邮件通知会用到。
   router_id LVS_k8s
}

# 用来做健康检查的，当时检查失败时会将 vrrp_instance 的 priority 减少相应的值。
vrrp_script check_haproxy {
    script "killall -0 haproxy" #根据进程名称检测进程是否存活 interval 3 weight -2 fall 10 rise 2 } # rp_instance用来定义对外提供服务的 VIP 区域及其相关属性。 vrrp_instance VI_1 { state MASTER #当前节点为MASTER，其他两个节点设置为BACKUP interface ens33 #改为自己的网卡 virtual_router_id 51 priority 250 advert_int 1 authentication { auth_type PASS auth_pass 35f18af7190d51c9f7f78f37300a0cbd } virtual_ipaddress { 192.168.2.10 #虚拟ip，即VIP } track_script { check_haproxy } } EOF 

当前节点的配置中 state 配置为 MASTER，其它两个节点设置为 BACKUP

配置说明：

• virtual_ipaddress： vip
• track_script： 执行上面定义好的检测的script
• interface： 节点固有IP（非VIP）的网卡，用来发VRRP包。
• virtual_router_id： 取值在0-255之间，用来区分多个instance的VRRP组播
• advert_int： 发VRRP包的时间间隔，即多久进行一次master选举（可以认为是健康查检时间间隔）。
• authentication： 认证区域，认证类型有PASS和HA（IPSEC），推荐使用PASS（密码只识别前8位）。
• state： 可以是MASTER或BACKUP，不过当其他节点keepalived启动时会将priority比较大的节点选举为MASTER，因此该项其实没有实质用途。
• priority： 用来选举master的，要成为master，那么这个选项的值最好高于其他机器50个点，该项取值范围是1-255（在此范围之外会被识别成默认值100）。

3、启动Keepalived

# 设置开机启动
systemctl enable keepalived
# 启动keepalived
systemctl start keepalived
# 查看启动状态
systemctl status keepalived

4、查看网络状态

kepplived 配置中 state 为 MASTER 的节点启动后，查看网络状态，可以看到虚拟IP已经加入到绑定的网卡中

ip address show ens33

当关掉当前节点的keeplived服务后将进行虚拟IP转移，将会推选state 为 BACKUP 的节点的某一节点为新的MASTER，可以在那台节点上查看网卡，将会查看到虚拟IP

四、安装haproxy

此处的haproxy为apiserver提供反向代理，haproxy将所有请求轮询转发到每个master节点上。相对于仅仅使用keepalived主备模式仅单个master节点承载流量，这种方式更加合理、健壮。

1、yum安装haproxy

yum install -y haproxy

2、配置haproxy

cat > /etc/haproxy/haproxy.cfg << EOF
#---------------------------------------------------------------------
# Global settings
#---------------------------------------------------------------------
global
    # to have these messages end up in /var/log/haproxy.log you will
    # need to: # 1) configure syslog to accept network log events. This is done # by adding the '-r' option to the SYSLOGD_OPTIONS in # /etc/sysconfig/syslog # 2) configure local2 events to go to the /var/log/haproxy.log # file. A line like the following can be added to # /etc/sysconfig/syslog # # local2.* /var/log/haproxy.log # log 127.0.0.1 local2 chroot /var/lib/haproxy pidfile /var/run/haproxy.pid maxconn 4000 user haproxy group haproxy daemon # turn on stats unix socket stats socket /var/lib/haproxy/stats #--------------------------------------------------------------------- # common defaults that all the 'listen' and 'backend' sections will # use if not designated in their block #--------------------------------------------------------------------- defaults mode http log global option httplog option dontlognull option http-server-close option forwardfor except 127.0.0.0/8 option redispatch retries 3 timeout http-request 10s timeout queue 1m timeout connect 10s timeout client 1m timeout server 1m timeout http-keep-alive 10s timeout check 10s maxconn 3000 #--------------------------------------------------------------------- # kubernetes apiserver frontend which proxys to the backends #--------------------------------------------------------------------- frontend kubernetes-apiserver mode tcp bind *:16443 option tcplog default_backend kubernetes-apiserver #--------------------------------------------------------------------- # round robin balancing between the various backends #--------------------------------------------------------------------- backend kubernetes-apiserver mode tcp balance roundrobin server master01.k8s.io 192.168.2.11:6443 check server master02.k8s.io 192.168.2.12:6443 check server master03.k8s.io 192.168.2.13:6443 check #--------------------------------------------------------------------- # collection haproxy statistics message #--------------------------------------------------------------------- listen stats bind *:1080 stats auth admin:awesomePassword stats refresh 5s stats realm HAProxy\ Statistics stats uri /admin?stats EOF 

haproxy配置在其他master节点上(192.168.2.12和192.168.2.13)相同

3、启动并检测haproxy

# 设置开机启动
systemctl enable haproxy
# 开启haproxy
systemctl start haproxy
# 查看启动状态
systemctl status haproxy

4、检测haproxy端口

ss -lnt | grep -E "16443|1080"

显示：

五、安装Docker (所有节点)

1、移除之前安装过的Docker

sudo yum remove docker \
                  docker-client \
                  docker-client-latest \
                  docker-common \
                  docker-latest \
                  docker-latest-logrotate \
                  docker-logrotate \
                  docker-selinux \
                  docker-engine-selinux \
                  docker-ce-cli \
                  docker-engine

查看还有没有存在的docker组件

rpm -qa|grep docker

有则通过命令 yum -y remove XXX 来删除,比如：

yum remove docker-ce-cli

2、配置docker的yum源

下面两个镜像源选择其一即可，由于官方下载速度比较慢，推荐用阿里镜像源

• 阿里镜像源

sudo yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

• Docker官方镜像源

sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo

2、安装Docker：

显示docker-ce所有可安装版本：

yum list docker-ce --showduplicates | sort -r

安装指定docker版本

sudo yum install docker-ce-18.06.1.ce-3.el7 -y

设置镜像存储目录

找到大点的挂载的目录进行存储

# 修改docker配置
vi /lib/systemd/system/docker.service

找到这行，王后面加上存储目录，例如这里是 --graph /apps/docker
ExecStart=/usr/bin/docker --graph /apps/docker

启动docker并设置docker开机启动

systemctl enable docker
systemctl start docker

确认一下iptables

确认一下iptables filter表中FOWARD链的默认策略(pllicy)为ACCEPT。

iptables -nvL

显示：

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         
    0     0 DOCKER-USER  all  --  *      *       0.0.0.0/0            0.0.0.0/0           
    0     0 DOCKER-ISOLATION-STAGE-1  all  --  *      *       0.0.0.0/0            0.0.0.0/0           
    0     0 ACCEPT     all  --  *      docker0  0.0.0.0/0            0.0.0.0/0            ctstate RELATED,ESTABLISHED
    0     0 DOCKER     all  --  *      docker0  0.0.0.0/0            0.0.0.0/0           
    0     0 ACCEPT     all  --  docker0 !docker0  0.0.0.0/0            0.0.0.0/0           
    0     0 ACCEPT     all  --  docker0 docker0  0.0.0.0/0            0.0.0.0/0            

Docker从1.13版本开始调整了默认的防火墙规则，禁用了iptables filter表中FOWARD链，这样会引起Kubernetes集群中跨Node的Pod无法通信。但这里通过安装docker 1806，发现默认策略又改回了ACCEPT，这个不知道是从哪个版本改回的，因为我们线上版本使用的1706还是需要手动调整这个策略的。

六、安装kubeadm、kubelet

1、配置可用的国内yum源用于安装：

cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF

2、安装kubelet

• 需要在每台机器上都安装以下的软件包：

  • kubeadm: 用来初始化集群的指令。
  • kubelet: 在集群中的每个节点上用来启动 pod 和 container 等。
  • kubectl: 用来与集群通信的命令行工具。

查看kubelet版本列表

yum list kubelet --showduplicates | sort -r 

安装kubelet

yum install -y kubelet-1.13.4-0

启动kubelet并设置开机启动

systemctl enable kubelet 
systemctl start kubelet

检查状态

检查状态,发现是failed状态，正常，kubelet会10秒重启一次，等初始化master节点后即可正常

systemctl status kubelet

3、安装kubeadm

负责初始化集群

查看kubeadm版本列表

yum list kubeadm --showduplicates | sort -r 

安装kubeadm

yum install -y kubeadm-1.13.4-0

安装 kubeadm 时候会默认安装 kubectl ，所以不需要单独安装kubectl

4、重启服务器

为了防止发生某些未知错误，这里我们重启下服务器，方便进行后续操作

reboot

七、初始化第一个kubernetes master节点

因为需要绑定虚拟IP，所以需要首先先查看虚拟IP启动这几台master机子哪台上

ip address show ens33

显示：

 ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:7e:65:b3 brd ff:ff:ff:ff:ff:ff
    inet 192.168.2.11/24 brd 192.168.2.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet 192.168.2.10/32 scope global ens33
       valid_lft forever preferred_lft forever

可以看到 10虚拟ip 和 11的ip 在一台机子上，所以初始化kubernetes第一个master要在master01机子上进行安装

1、创建kubeadm配置的yaml文件

cat > kubeadm-config.yaml << EOF
apiServer:
  certSANs:
    - k8s-master-01
    - k8s-master-02
    - k8s-master-03
    - master.k8s.io
    - 192.168.2.10
    - 192.168.2.11
    - 192.168.2.12
    - 192.168.2.13
    - 127.0.0.1
  extraArgs:
    authorization-mode: Node,RBAC
  timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta1
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controlPlaneEndpoint: "master.k8s.io:16443"
controllerManager: {}
dns: 
  type: CoreDNS
etcd:
  local:    
    dataDir: /var/lib/etcd
imageRepository: registry.aliyuncs.com/google_containers
kind: ClusterConfiguration
kubernetesVersion: v1.13.4
networking: 
  dnsDomain: cluster.local  
  podSubnet: 10.20.0.0/16
  serviceSubnet: 10.10.0.0/16
scheduler: {}
EOF

以下两个地方设置： - certSANs： 虚拟ip地址（为了安全起见，把所有集群地址都加上） - controlPlaneEndpoint： 虚拟IP:监控端口号

配置说明：

• imageRepository： registry.aliyuncs.com/google_containers (使用阿里云镜像仓库)
• podSubnet： 10.20.0.0/16 (pod地址池)
• serviceSubnet： 10.10.0.0/16

#service地址池

2、初始化第一个master节点

kubeadm init --config kubeadm-config.yaml 

日志：

Your Kubernetes master has initialized successfully!

To start using your cluster, you need to run the following as a regular user:

  mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config

You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
  https://kubernetes.io/docs/concepts/cluster-administration/addons/

You can now join any number of machines by running the following on each node
as root:

  kubeadm join master.k8s.io:16443 --token dm3cw1.kw4hq84ie1376hji --discovery-token-ca-cert-hash sha256:f079b624773145ba714b56e177f52143f90f75a1dcebabda6538a49e224d4009

在此处看日志可以知道，通过

kubeadm join master.k8s.io:16443 --token dm3cw1.kw4hq84ie1376hji --discovery-token-ca-cert-hash sha256:f079b624773145ba714b56e177f52143f90f75a1dcebabda6538a49e224d4009

来让节点加入集群

3、配置kubectl环境变量

配置环境变量

mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

4、查看组件状态

kubectl get cs

显示：

NAME                 STATUS    MESSAGE              ERROR
controller-manager   Healthy   ok                   
scheduler            Healthy   ok                   
etcd-0               Healthy   {"health": "true"}   

查看pod状态

kubectl get pods --namespace=kube-system

显示：

可以看到coredns没有启动，这是由于还没有配置网络插件，接下来配置下后再重新查看启动状态

八、安装网络插件

1、配置flannel插件的yaml文件

cat > kube-flannel.yaml << EOF
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1beta1 metadata:  name: flannel rules:  - apiGroups:  - ""  resources:  - pods  verbs:  - get  - apiGroups:  - ""  resources:  - nodes  verbs:  - list  - watch  - apiGroups:  - ""  resources:  - nodes/status  verbs:  - patch --- kind: ClusterRoleBinding apiVersion: rbac.authorization.k8s.io/v1beta1 metadata:  name: flannel roleRef:  apiGroup: rbac.authorization.k8s.io  kind: ClusterRole  name: flannel subjects: - kind: ServiceAccount  name: flannel  namespace: kube-system --- apiVersion: v1 kind: ServiceAccount metadata:  name: flannel  namespace: kube-system --- kind: ConfigMap apiVersion: v1 metadata:  name: kube-flannel-cfg  namespace: kube-system  labels:  tier: node  app: flannel data: cni-conf.json: | { "name": "cbr0", "plugins": [ { "type": "flannel", "delegate": { "hairpinMode": true, "isDefaultGateway": true } }, { "type": "portmap", "capabilities": { "portMappings": true } } ] } net-conf.json: | { "Network": "10.20.0.0/16", "Backend": { "Type": "vxlan" } } --- apiVersion: extensions/v1beta1 kind: DaemonSet metadata:  name: kube-flannel-ds-amd64  namespace: kube-system  labels:  tier: node  app: flannel spec:  template:  metadata:  labels:  tier: node  app: flannel  spec:  hostNetwork: true  nodeSelector: beta.kubernetes.io/arch: amd64  tolerations:  - operator: Exists  effect: NoSchedule  serviceAccountName: flannel  initContainers:  - name: install-cni  image: registry.cn-shenzhen.aliyuncs.com/cp_m/flannel:v0.10.0-amd64  command:  - cp  args:  - -f  - /etc/kube-flannel/cni-conf.json  - /etc/cni/net.d/10-flannel.conflist  volumeMounts:  - name: cni  mountPath: /etc/cni/net.d  - name: flannel-cfg  mountPath: /etc/kube-flannel/  containers:  - name: kube-flannel  image: registry.cn-shenzhen.aliyuncs.com/cp_m/flannel:v0.10.0-amd64  command:  - /opt/bin/flanneld  args:  - --ip-masq  - --kube-subnet-mgr  resources:  requests:  cpu: "100m"  memory: "50Mi"  limits:  cpu: "100m"  memory: "50Mi"  securityContext:  privileged: true  env:  - name: POD_NAME  valueFrom:  fieldRef:  fieldPath: metadata.name  - name: POD_NAMESPACE  valueFrom:  fieldRef:  fieldPath: metadata.namespace  volumeMounts:  - name: run  mountPath: /run  - name: flannel-cfg  mountPath: /etc/kube-flannel/  volumes:  - name: run  hostPath:  path: /run  - name: cni  hostPath:  path: /etc/cni/net.d  - name: flannel-cfg  configMap:  name: kube-flannel-cfg EOF 

“Network”: “10.20.0.0/16”要和kubeadm-config.yaml配置文件中podSubnet: 10.20.0.0/16相同

2、创建flanner相关role和pod

kubectl apply -f kube-flannel.yaml

等待一会时间，再次查看各个pods的状态

kubectl get pods --namespace=kube-system

显示：

可以看到coredns已经启动

九、加入集群

1、Master加入集群构成高可用

复制秘钥到各个节点

在master01 服务器上执行下面命令，将kubernetes相关文件复制到 master02、master03

如果其他节点为初始化第一个master节点，则将该节点的配置文件复制到其余两个主节点，例如master03为第一个master节点，则将它的k8s配置复制到master02和master01。

• 复制文件到 master02

ssh [email protected] mkdir -p /etc/kubernetes/pki/etcd
scp /etc/kubernetes/admin.conf [email protected]:/etc/kubernetes
scp /etc/kubernetes/pki/{ca.*,sa.*,front-proxy-ca.*} [email protected]:/etc/kubernetes/pki
scp /etc/kubernetes/pki/etcd/ca.* [email protected]:/etc/kubernetes/pki/etcd

• 复制文件到 master03

ssh [email protected] mkdir -p /etc/kubernetes/pki/etcd
scp /etc/kubernetes/admin.conf [email protected]:/etc/kubernetes
scp /etc/kubernetes/pki/{ca.*,sa.*,front-proxy-ca.*} [email protected]:/etc/kubernetes/pki
scp /etc/kubernetes/pki/etcd/ca.* [email protected]:/etc/kubernetes/pki/etcd

• master节点加入集群

master02 和 master03 服务器上都执行加入集群操作

kubeadm join master.k8s.io:16443 --token dm3cw1.kw4hq84ie1376hji --discovery-token-ca-cert-hash sha256:f079b624773145ba714b56e177f52143f90f75a1dcebabda6538a49e224d4009 --experimental-control-plane

如果加入失败想重新尝试，请输入 kubeadm reset 命令清除之前的设置，重新执行从“复制秘钥”和“加入集群”这两步

显示安装过程:

......
This node has joined the cluster and a new control plane instance was created:

* Certificate signing request was sent to apiserver and approval was received.
* The Kubelet was informed of the new secure connection details.
* Master label and taint were applied to the new node.
* The Kubernetes control plane instances scaled up.
* A new etcd member was added to the local/stacked etcd cluster.

To start administering your cluster from this node, you need to run the following as a regular user:

	mkdir -p $HOME/.kube
	sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
	sudo chown $(id -u):$(id -g) $HOME/.kube/config

Run 'kubectl get nodes' to see this node join the cluster. 

• 配置kubectl环境变量

mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

2、node节点加入集群

除了让master节点加入集群组成高可用外，slave节点也要加入集群中。

这里将k8s-node-01、k8s-node-02加入集群，进行工作

输入初始化k8s master时候提示的加入命令，如下：

kubeadm join master.k8s.io:16443 --token dm3cw1.kw4hq84ie1376hji --discovery-token-ca-cert-hash sha256:f079b624773145ba714b56e177f52143f90f75a1dcebabda6538a49e224d4009 

3、如果忘记加入集群的token和sha256 (如正常则跳过)

• 显示获取token列表

kubeadm token list

默认情况下 Token 过期是时间是24小时，如果 Token 过期以后，可以输入以下命令，生成新的 Token

kubeadm token create

• 获取ca证书sha256编码hash值

openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | openssl dgst -sha256 -hex | sed 's/^.* //'

• 拼接命令

kubeadm join master.k8s.io:16443 --token 882ik4.9ib2kb0eftvuhb58 --discovery-token-ca-cert-hash sha256:0b1a836894d930c8558b350feeac8210c85c9d35b6d91fde202b870f3244016a 

如果是master加入，请在最后面加上 –experimental-control-plane 这个参数

4、查看各个节点加入集群情况

kubectl get nodes -o wide

显示：

NAME            STATUS   ROLES    AGE   VERSION   INTERNAL-IP    EXTERNAL-IP   OS-IMAGE                KERNEL-VERSION              CONTAINER-RUNTIME
k8s-master-01   Ready    master   12m   v1.13.4   192.168.2.11   <none>        CentOS Linux 7 (Core)   3.10.0-957.1.3.el7.x86_64   docker://18.6.1
k8s-master-02   Ready    master   10m   v1.13.4   192.168.2.12   <none>        CentOS Linux 7 (Core)   3.10.0-957.1.3.el7.x86_64   docker://18.6.1
k8s-master-03   Ready    master   38m   v1.13.4   192.168.2.13   <none>        CentOS Linux 7 (Core)   3.10.0-957.1.3.el7.x86_64   docker://18.6.1
k8s-node-01     Ready    <none>   68s   v1.13.4   192.168.2.21   <none>        CentOS Linux 7 (Core)   3.10.0-957.1.3.el7.x86_64   docker://18.6.1
k8s-node-02     Ready    <none>   61s   v1.13.4   192.168.2.22   <none>        CentOS Linux 7 (Core)   3.10.0-957.1.3.el7.x86_64   docker://18.6.1

十、从集群中删除 Node

• Master节点：

kubectl drain <node name> --delete-local-data --force --ignore-daemonsets
kubectl delete node <node name>

• slave节点

kubeadm reset

十一、配置dashboard

这个在一个服务器上部署，其他服务器会复制这个部署的pod，所以这里在master01服务器上部署 dashboard

1、创建 dashboard.yaml 并启动

# ------------------- Dashboard Secret ------------------- #
apiVersion: v1
kind: Secret metadata:  labels:  k8s-app: kubernetes-dashboard  name: kubernetes-dashboard-certs  namespace: kube-system type: Opaque --- # ------------------- Dashboard Service Account ------------------- # apiVersion: v1 kind: ServiceAccount metadata:  labels:  k8s-app: kubernetes-dashboard  name: kubernetes-dashboard  namespace: kube-system --- # ------------------- Dashboard Role & Role Binding ------------------- # kind: Role apiVersion: rbac.authorization.k8s.io/v1 metadata:  name: kubernetes-dashboard-minimal  namespace: kube-system rules: # Allow Dashboard to create 'kubernetes-dashboard-key-holder' secret. - apiGroups: [""]  resources: ["secrets"]  verbs: ["create"] # Allow Dashboard to create 'kubernetes-dashboard-settings' config map. - apiGroups: [""]  resources: ["configmaps"]  verbs: ["create"] # Allow Dashboard to get, update and delete Dashboard exclusive secrets. - apiGroups: [""]  resources: ["secrets"]  resourceNames: ["kubernetes-dashboard-key-holder", "kubernetes-dashboard-certs"]  verbs: ["get", "update", "delete"] # Allow Dashboard to get and update 'kubernetes-dashboard-settings' config map. - apiGroups: [""]  resources: ["configmaps"]  resourceNames: ["kubernetes-dashboard-settings"]  verbs: ["get", "update"] # Allow Dashboard to get metrics from heapster. - apiGroups: [""]  resources: ["services"]  resourceNames: ["heapster"]  verbs: ["proxy"] - apiGroups: [""]  resources: ["services/proxy"]  resourceNames: ["heapster", "http:heapster:", "https:heapster:"]  verbs: ["get"] --- apiVersion: rbac.authorization.k8s.io/v1 kind: RoleBinding metadata:  name: kubernetes-dashboard-minimal  namespace: kube-system roleRef:  apiGroup: rbac.authorization.k8s.io  kind: Role  name: kubernetes-dashboard-minimal subjects: - kind: ServiceAccount  name: kubernetes-dashboard  namespace: kube-system --- # ------------------- Dashboard Deployment ------------------- # # 1.修改了镜像仓库位置，编辑成自己的镜像仓库 # 2.变更了镜像拉去策略imagePullPolicy: IfNotPresent kind: Deployment apiVersion: apps/v1 metadata:  labels:  k8s-app: kubernetes-dashboard  name: kubernetes-dashboard  namespace: kube-system spec:  replicas: 1  revisionHistoryLimit: 10  selector:  matchLabels:  k8s-app: kubernetes-dashboard  template:  metadata:  labels:  k8s-app: kubernetes-dashboard  spec:  containers:  - name: kubernetes-dashboard  image: registry.cn-hangzhou.aliyuncs.com/google_containers/kubernetes-dashboard-amd64:v1.10.1  imagePullPolicy: IfNotPresent  ports:  - containerPort: 8443  protocol: TCP  args:  - --auto-generate-certificates # Uncomment the following line to manually specify Kubernetes API server Host # If not specified, Dashboard will attempt to auto discover the API server and connect # to it. Uncomment only if the default does not work. # - --apiserver-host=http://my-address:port  volumeMounts:  - name: kubernetes-dashboard-certs  mountPath: /certs # Create on-disk volume to store exec logs  - mountPath: /tmp  name: tmp-volume  livenessProbe:  httpGet:  scheme: HTTPS  path: /  port: 8443  initialDelaySeconds: 30  timeoutSeconds: 30  volumes:  - name: kubernetes-dashboard-certs  secret:  secretName: kubernetes-dashboard-certs  - name: tmp-volume  emptyDir: {}  serviceAccountName: kubernetes-dashboard # Comment the following tolerations if Dashboard must not be deployed on master  tolerations:  - key: node-role.kubernetes.io/master  effect: NoSchedule --- # ------------------- Dashboard Service ------------------- # # 增加了nodePort，使得能够访问,改变默认的type类型ClusterIP，变为NodePort # 如果不配置的话默认只能集群内访问 kind: Service apiVersion: v1 metadata:  labels:  k8s-app: kubernetes-dashboard  name: kubernetes-dashboard  namespace: kube-system spec:  type: NodePort  ports:  - port: 443  targetPort: 8443  nodePort: 30001  selector:  k8s-app: kubernetes-dashboard 

运行 dashboard

kubectl create -f kubernetes-dashboard.yaml

2、Dashboard 创建 ServiceAccount 并绑定 Admin 角色

kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:  name: admin  annotations: rbac.authorization.kubernetes.io/autoupdate: "true" roleRef:  kind: ClusterRole  name: cluster-admin  apiGroup: rbac.authorization.k8s.io subjects: - kind: ServiceAccount  name: admin  namespace: kube-system --- apiVersion: v1 kind: ServiceAccount metadata:  name: admin  namespace: kube-system  labels: kubernetes.io/cluster-service: "true" addonmanager.kubernetes.io/mode: Reconcile 

运行dashboard的用户和角色绑定

kubectl create -f dashboard-user-role.yaml

获取登陆token

kubectl describe secret/$(kubectl get secret -n kube-system |grep admin|awk '{print $1}') -n kube-system

显示：

[root@k8s-master-01 local]# kubectl describe secret/$(kubectl get secret -nkube-system |grep admin|awk '{print $1}') -nkube-system
Name:         admin-token-2mfdz
Namespace:    kube-system
Labels:       <none>
Annotations:  kubernetes.io/service-account.name: admin
              kubernetes.io/service-account.uid: 74efd994-38d8-11e9-8740-000c299624e4

Type:  kubernetes.io/service-account-token

Data
====
ca.crt:     1025 bytes
namespace:  11 bytes

token:

eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJhZG1pbi10b2tlbi1qdjd4ayIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50Lm5hbWUiOiJhZG1pbiIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50LnVpZCI6ImM4ZTMxYzk0LTQ2MWEtMTFlOS1iY2M5LTAwMGMyOTEzYzUxZCIsInN1YiI6InN5c3RlbTpzZXJ2aWNlYWNjb3VudDprdWJlLXN5c3RlbTphZG1pbiJ9.TNw1iFEsZmJsVG4cki8iLtEoiY1pjpnOYm8ZIFjctpBdTOw6kUMvv2b2B2BJ_5rFle31gqGAZBIRyYj9LPAs06qT5uVP_l9o7IyFX4HToBF3veiun4e71822eQRUsgqiPh5uSjKXEkf9yGq9ujiCdtzFxnp3Pnpeuge73syuwd7J6F0-dJAp3b48MLZ1JJwEo6CTCMhm9buysycUYTbT_mUDQMNrHVH0868CdN_H8azA4PdLLLrFfTiVgoGu4c3sG5rgh9kKFqZA6dzV0Kq10W5JJwJRM1808ybLHyV9jfKN8N2_lZ7ehE6PbPU0cV-PyP74iA-HrzFW1yVwSLPVYA

3、运行dashboard并登陆

输入地址：https://192.168.2.10:30001 进入 dashboard 界面

这里输入上面获取的 token 进入 dashboard

问题

1、Master不会参与负载工作

Master不会参与负载工作，如何让其参加，这里需要了解traint

查看traint

# 查看全部节点是否能被安排工作
kubectl describe nodes | grep -E '(Roles|Taints)'

删除traint

# 所有node都可以调度
kubectl taint nodes --all node-role.kubernetes.io/master-
# 指定node可以调度
kubectl taint nodes k8s-master-01 node-role.kubernetes.io/master-

2、重新加入集群

有时候节点出现问题需要重新加入集群，加入前需要清除一些设置，不然可能出现某些错误，比如

network is not ready: [runtime network not ready: NetworkReady=false reason:NetworkPluginNotReady message:docker: network plugin is not ready: cni config uninitialized]
Back-off restarting failed container 

按下面步骤执行，再执行加入集群命令即可

#重置kubernetes服务，重置网络。删除网络配置，link
kubeadm reset

#重启kubelet
systemctl stop kubelet

#停止docker
systemctl stop docker

#重置cni
rm -rf /var/lib/cni/
rm -rf /var/lib/kubelet/*
rm -rf /etc/cni/
ifconfig cni0 down
ifconfig flannel.1 down
ifconfig docker0 down
ip link delete cni0
ip link delete flannel.1

#重启docker systemctl start docker 

再次加入集群

kubeadm join cluster.kube.com:16443 --token gaeyou.k2650x660c8eb98c --discovery-token-ca