1. 简介

测试环境Kubernetes 1.14.2版本高可用搭建文档，搭建方式为kubeadm

2. 服务器版本和架构信息

系统版本：CentOS Linux release 7.6.1810 (Core)
内核：4.4.184-1.el7.elrepo.x86_64    注意：有可能后面安装的内核版本高于此版本
Kubernetes: v1.14.2
Docker-ce: 18.06
网络组件：calico
硬件配置：16核64G

Keepalived保证apiserever服务器的IP高可用
Haproxy实现apiserver的负载均衡

3. 服务器角色规划

一定注意对应自己的服务器IP和主机名

master01/02节点上面部署了kubelet、keepalived、haproxy、controllmanager、apiserver、scheduler、docker、kube-proxy、calico组件

master03节点上面部署了kubelet、controllmanager、apiserver、scheduler、docker、kube-proxy、calico组件

node01/node02节点上面部署了kubelet、kube-proxy、docker、calico组件

其中除了kubelet和docker组件，其他组件都是以静态pod模式存在

节点名称	角色	IP	安装软件
负载VIP	VIP	172.16.4.231
master-01	master	172.16.4.129	kubeadm、kubelet、kubectl、docker、haproxy、keepalived
master-02	master	172.16.4.130	kubeadm、kubelet、kubectl、docker、haproxy、keepalived
master-03	master	172.16.4.133	kubeadm、kubelet、kubectl、docker
node-01	node	172.16.4.128	kubeadm、kubelet、kubectl、docker
node-03	node	172.16.4.132	kubeadm、kubelet、kubectl、docker
service网段		10.209.0.0/16

4. 服务器初始化

4.1 关闭Selinux/firewalld/iptables(所有机器执行)

setenforce 0 \
&& sed -i 's/^SELINUX=.*$/SELINUX=disabled/' /etc/selinux/config \
&& getenforce

systemctl stop firewalld \
&& systemctl daemon-reload \
&& systemctl disable firewalld \
&& systemctl daemon-reload \
&& systemctl status firewalld

yum install -y iptables-services \
&& systemctl stop iptables \
&& systemctl disable iptables \
&& systemctl status iptables

4.2 为每台服务器添加host解析记录(所有机器执行)

cat >>/etc/hosts<<EOF
172.16.4.129 master01
172.16.4.130 master02
172.16.4.133 master03
172.16.4.128 node01
172.16.4.132 node03
EOF

4.3 更换阿里源(所有机器执行)

yum install wget -y
cp -r /etc/yum.repos.d /etc/yum.repos.d.bak
rm -f /etc/yum.repos.d/*.repo
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo \
&& wget -O /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo

yum clean all && yum makecache

4.4 设置limits.conf(所有机器执行)

cat >> /etc/security/limits.conf <<EOF
# End of file
* soft nproc 10240000
* hard nproc 10240000
* soft nofile 10240000
* hard nofile 10240000
EOF

4.5 设置sysctl.conf(所有机器执行)

[ ! -e "/etc/sysctl.conf_bk" ] && /bin/mv /etc/sysctl.conf{,_bk} \
&& cat > /etc/sysctl.conf << EOF
fs.file-max=1000000
fs.nr_open=20480000
net.ipv4.tcp_max_tw_buckets = 180000
net.ipv4.tcp_sack = 1
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_rmem = 4096 87380 4194304
net.ipv4.tcp_wmem = 4096 16384 4194304
net.ipv4.tcp_max_syn_backlog = 16384
net.core.netdev_max_backlog = 32768
net.core.somaxconn = 32768
net.core.wmem_default = 8388608
net.core.rmem_default = 8388608
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_timestamps = 0
net.ipv4.tcp_fin_timeout = 20
net.ipv4.tcp_synack_retries = 2
net.ipv4.tcp_syn_retries = 2
net.ipv4.tcp_syncookies = 1
#net.ipv4.tcp_tw_len = 1
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_mem = 94500000 915000000 927000000
net.ipv4.tcp_max_orphans = 3276800
net.ipv4.ip_local_port_range = 1024 65000
#net.nf_conntrack_max = 6553500
#net.netfilter.nf_conntrack_max = 6553500
#net.netfilter.nf_conntrack_tcp_timeout_close_wait = 60
#net.netfilter.nf_conntrack_tcp_timeout_fin_wait = 120
#net.netfilter.nf_conntrack_tcp_timeout_time_wait = 120
#net.netfilter.nf_conntrack_tcp_timeout_established = 3600
EOF

sysctl -p

4.6 配置时间同步(所有机器执行)

ntpdate -u pool.ntp.org
crontab -e       #加入定时任务
*/15 * * * * /usr/sbin/ntpdate -u pool.ntp.org >/dev/null 2>&1

4.7 配置k8s.conf(所有机器执行)

cat <<EOF >  /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1
vm.swappiness=0
EOF

#执行命令使其修改生效
modprobe br_netfilter \
&& sysctl -p /etc/sysctl.d/k8s.conf

4.8 关闭交换分区(所有机器执行)

swapoff -a
yes | cp /etc/fstab /etc/fstab_bak
cat /etc/fstab_bak |grep -v swap > /etc/fstab

4.9 升级系统内核(所有机器执行)

yum update -y

rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-2.el7.elrepo.noarch.rpm ;yum --enablerepo=elrepo-kernel install kernel-lt-devel kernel-lt -y

查看内核修改结果
grub2-editenv list  

#注意，这里执行下面的命令会出现多个内核版本
[root@master01 ~]# cat /boot/grub2/grub.cfg |grep "menuentry "
menuentry 'CentOS Linux (4.4.184-1.el7.elrepo.x86_64) 7 (Core)' --class centos --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-3.10.0-862.el7.x86_64-advanced-021a955b-781d-425a-8250-f39857437658' 


设置默认内核版本，改版本必须已经存在，请注意执行命令cat /boot/grub2/grub.cfg |grep "menuentry "后生成的内容，切勿随意复制
grub2-set-default 'CentOS Linux (4.4.184-1.el7.elrepo.x86_64) 7 (Core)'

查看内核修改结果
grub2-editenv list  

# 检查默认内核版本高于4.1，否则请调整默认启动参数
# 查看内核修改结果
grub2-editenv list  

#重启以更换内核使其生效
reboot

4.10 加载ipvs模块(所有机器执行)

cat > /etc/sysconfig/modules/ipvs.modules <<EOF
#!/bin/bash
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
EOF
chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules && lsmod | grep -e ip_vs -e nf_conntrack_ipv4

4.11 添加k8s yum源(所有机器执行)

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=1
repo_gpgcheck=1
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF

4.12 安装服务器必备软件

yum -y install wget vim iftop iotop net-tools nmon telnet lsof iptraf nmap httpd-tools lrzsz mlocate ntp ntpdate strace libpcap nethogs iptraf iftop nmon bridge-utils bind-utils telnet nc nfs-utils rpcbind nfs-utils dnsmasq python python-devel tcpdump mlocate tree 

5. 安装keepalived和haproxy

5.1 在master01和master02上安装keepalived和haproxy

master01的priority为250，master02的priority为200，其他配置一样。

master01(172.16.4.129)

vim /etc/keepalived/keepalived.conf

注意interface这个配置，配置成你服务器的网卡，切勿随意粘贴

! Configuration File for keepalived

global_defs {
   router_id LVS_DEVEL
}

vrrp_script check_haproxy {
    script "killall -0 haproxy"
    interval 3
    weight -2
    fall 10
    rise 2
}

vrrp_instance VI_1 {
    state MASTER
    interface ens160
    virtual_router_id 51
    priority 250
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 35f18af7190d51c9f7f78f37300a0cbd
    }
    virtual_ipaddress {
        172.16.4.231
    }
    track_script {
        check_haproxy
    }
}

master02(172.16.4.130)

vim /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {
   router_id LVS_DEVEL
}

vrrp_script check_haproxy {
    script "killall -0 haproxy"
    interval 3
    weight -2
    fall 10
    rise 2
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens160
    virtual_router_id 51
    priority 200
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 35f18af7190d51c9f7f78f37300a0cbd
    }
    virtual_ipaddress {
        172.16.4.231
    }
    track_script {
        check_haproxy
    }
}

5.2 haproxy配置

master01和master02的haproxy配置是一样的。此处我们监听的是172.16.4.231的8443端口，因为haproxy是和k8s apiserver是部署在同一台服务器上，都用6443会冲突。

172.16.4.129
vim /etc/haproxy/haproxy.cfg

#---------------------------------------------------------------------
# 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
    log 127.0.0.1 local0 info

    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                 *:8443
    option               tcplog
    default_backend      kubernetes-apiserver

#---------------------------------------------------------------------
# round robin balancing between the various backends
#---------------------------------------------------------------------
backend kubernetes-apiserver
    mode        tcp
    balance     roundrobin
    server master01 172.16.4.129:6443 check
    server master02 172.16.4.130:6443 check
    server master03 172.16.4.133:6443 check

#---------------------------------------------------------------------
# collection haproxy statistics message
#---------------------------------------------------------------------
listen stats
    bind                 *:1080
    stats auth           admin:awesomePassword
    stats refresh        5s
    stats realm          HAProxy\ Statistics
    stats uri            /admin?stats

172.16.4.130
vim /etc/haproxy/haproxy.cfg

#---------------------------------------------------------------------

# 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
    log 127.0.0.1 local0 info

​```
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                 *:8443
    option               tcplog
    default_backend      kubernetes-apiserver

#---------------------------------------------------------------------

# round robin balancing between the various backends

#---------------------------------------------------------------------
backend kubernetes-apiserver
    mode        tcp
    balance     roundrobin
    server master01 172.16.4.129:6443 check
    server master02 172.16.4.130:6443 check
    server master03 172.16.4.133:6443 check

#---------------------------------------------------------------------

# collection haproxy statistics message

#---------------------------------------------------------------------
listen stats
    bind                 *:1080
    stats auth           admin:awesomePassword
    stats refresh        5s
    stats realm          HAProxy\ Statistics
    stats uri            /admin?stats

5.3 设置服务启动顺序及依赖关系（master01和master02操作）

vim /usr/lib/systemd/system/keepalived.service

[Unit]
Description=LVS and VRRP High Availability Monitor
After=syslog.target network-online.target haproxy.service
Requires=haproxy.service

5.4 启动服务

systemctl enable keepalived && systemctl start keepalived \
&& systemctl enable haproxy && systemctl start haproxy && systemctl status keepalived && systemctl status haproxy

6.安装docker

6.1 安装必要的一些系统工具（所有服务器安装）

yum install -y yum-utils device-mapper-persistent-data lvm2

6.2 添加软件源信息（所有服务器配置）

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

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

yum -y install docker-ce-18.06.3.ce-3.el7

usermod -aG docker bumblebee

6.3 配置daemon.json文件（所有服务器配置）

mkdir -p /etc/docker/ \
&& cat > /etc/docker/daemon.json << EOF
{
    "registry-mirrors":[
        "https://c6ai9izk.mirror.aliyuncs.com"
    ],
    "max-concurrent-downloads":3,
    "data-root":"/data/docker",
    "log-driver":"json-file",
    "log-opts":{
        "max-size":"100m",
        "max-file":"1"
    },
    "max-concurrent-uploads":5,
    "storage-driver":"overlay2",
    "storage-opts": [
    "overlay2.override_kernel_check=true"
  ]
}
EOF

6.4 启动检查docker服务

systemctl enable docker \
&& systemctl restart docker \
&& systemctl status docker

7 使用kubeadm部署kubernetes

7.1 配置kubernetes.repo(每台机器都需要配置)

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

7.2 安装必备软件(所有机器安装)

yum install -y kubelet-1.14.2 kubeadm-1.14.2 kubectl-1.14.2 ipvsadm ipset

#设置kubelet开机自启动,注意：这一步不能直接执行 systemctl start kubelet，会报错，成功初始化完后kubelet会自动起来
systemctl enable kubelet

7.3 修改初始化配置

使用kubeadm config print init-defaults > kubeadm-init.yaml 打印出默认配置，然后在根据自己的环境修改配置

注意需要修改advertiseAddress、controlPlaneEndpoint、imageRepository、serviceSubnet

其中advertiseAddress为master01的ip，controlPlaneEndpoint为VIP+8443端口，imageRepository修改为阿里的源，serviceSubnet找网络组要一段没人使用的IP段

[root@master01 ~]# cat kubeadm-init.yaml 
apiVersion: kubeadm.k8s.io/v1beta1
bootstrapTokens:
- groups:
  - system:bootstrappers:kubeadm:default-node-token
  token: abcdef.0123456789abcdef
  ttl: 24h0m0s
  usages:
  - signing
  - authentication
kind: InitConfiguration
localAPIEndpoint:
  advertiseAddress: 172.16.4.129
  bindPort: 6443
nodeRegistration:
  criSocket: /var/run/dockershim.sock
  name: master01
  taints:
  - effect: NoSchedule
    key: node-role.kubernetes.io/master
---
apiServer:
  timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta1
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controlPlaneEndpoint: "172.16.4.231:8443"
controllerManager: {}
dns:
  type: CoreDNS
etcd:
  local:
    dataDir: /var/lib/etcd
imageRepository: registry.cn-hangzhou.aliyuncs.com/google_containers
kind: ClusterConfiguration
kubernetesVersion: v1.14.2
networking:
  dnsDomain: cluster.local
  podSubnet: ""
  serviceSubnet: "10.209.0.0/16"
scheduler: {}

7.4 预下载镜像

[root@master01 ~]# kubeadm config images pull --config kubeadm-init.yaml
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver:v1.14.2
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager:v1.14.2
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler:v1.14.2
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy:v1.14.2
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/etcd:3.3.10
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:1.3.1

7.5 初始化

[root@master01 ~]# kubeadm init --config kubeadm-init.yaml
[init] Using Kubernetes version: v1.14.2
[preflight] Running pre-flight checks
	[WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Activating the kubelet service
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "etcd/ca" certificate and key
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [master01 localhost] and IPs [172.16.4.129 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [master01 localhost] and IPs [172.16.4.129 127.0.0.1 ::1]
[certs] Generating "ca" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [master01 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.209.0.1 172.16.4.129 172.16.4.231]
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Generating "front-proxy-ca" certificate and key
[certs] Generating "front-proxy-client" certificate and key
[certs] Generating "sa" key and public key
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
[kubeconfig] Writing "admin.conf" kubeconfig file
[endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
[kubeconfig] Writing "kubelet.conf" kubeconfig file
[endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
[kubeconfig] Writing "controller-manager.conf" kubeconfig file
[endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
[kubeconfig] Writing "scheduler.conf" kubeconfig file
[control-plane] Using manifest folder "/etc/kubernetes/manifests"
[control-plane] Creating static Pod manifest for "kube-apiserver"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
[wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
[apiclient] All control plane components are healthy after 17.506253 seconds
[upload-config] storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.14" in namespace kube-system with the configuration for the kubelets in the cluster
[upload-certs] Skipping phase. Please see --experimental-upload-certs
[mark-control-plane] Marking the node master01 as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node master01 as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: abcdef.0123456789abcdef
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstrap-token] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
[bootstrap-token] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
[bootstrap-token] creating the "cluster-info" ConfigMap in the "kube-public" namespace
[addons] Applied essential addon: CoreDNS
[endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
[addons] Applied essential addon: kube-proxy

Your Kubernetes control-plane 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 control-plane nodes by copying certificate authorities 
and service account keys on each node and then running the following as root:

  kubeadm join 172.16.4.231:8443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:0ca0a5fd28409faecba5d2f21aeb010a945a5dae42023fe361424d621708edc1 \
    --experimental-control-plane 	  

Then you can join any number of worker nodes by running the following on each as root:

kubeadm join 172.16.4.231:8443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:0ca0a5fd28409faecba5d2f21aeb010a945a5dae42023fe361424d621708edc1 

kubeadm init主要执行了以下操作：

• [init]：指定版本进行初始化操作
• [preflight] ：初始化前的检查和下载所需要的Docker镜像文件
• [kubelet-start] ：生成kubelet的配置文件”/var/lib/kubelet/config.yaml”，没有这个文件kubelet无法启动，所以初始化之前的kubelet实际上启动失败。
• [certificates]：生成Kubernetes使用的证书，存放在/etc/kubernetes/pki目录中。
• [kubeconfig] ：生成 KubeConfig 文件，存放在/etc/kubernetes目录中，组件之间通信需要使用对应文件。
• [control-plane]：使用/etc/kubernetes/manifest目录下的YAML文件，安装 Master 组件。
• [etcd]：使用/etc/kubernetes/manifest/etcd.yaml安装Etcd服务。
• [wait-control-plane]：等待control-plan部署的Master组件启动。
• [apiclient]：检查Master组件服务状态。
• [uploadconfig]：更新配置
• [kubelet]：使用configMap配置kubelet。
• [patchnode]：更新CNI信息到Node上，通过注释的方式记录。
• [mark-control-plane]：为当前节点打标签，打了角色Master，和不可调度标签，这样默认就不会使用Master节点来运行Pod。
• [bootstrap-token]：生成token记录下来，后边使用kubeadm join往集群中添加节点时会用到
• [addons]：安装附加组件CoreDNS和kube-proxy

7.6 为kubectl准备Kubeconfig文件

kubectl默认会在执行的用户家目录下面的.kube目录下寻找config文件。这里是将在初始化时[kubeconfig]步骤生成的admin.conf拷贝到.kube/config。

[root@master01 ~]# mkdir -p $HOME/.kube
[root@master01 ~]# sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
[root@master01 ~]# sudo chown $(id -u):$(id -g) $HOME/.kube/config

在该配置文件中，记录了API Server的访问地址，所以后面直接执行kubectl命令就可以正常连接到API Server中。

7.7 查看组件状态

[root@master01 ~]# kubectl get cs
NAME                 STATUS    MESSAGE             ERROR
controller-manager   Healthy   ok                  
scheduler            Healthy   ok                  
etcd-0               Healthy   {"health":"true"}   
[root@master01 ~]# kubectl get nodes
NAME       STATUS     ROLES    AGE     VERSION
master01   NotReady   master   4m20s   v1.14.2

目前只有一个节点，角色是Master，状态是NotReady，状态是NotReady状态是因为还没有安装网络插件

7.8 其他master部署(在master01机器上执行)

在master01将证书文件拷贝至master02、master03节点

#拷贝正式至master02节点
USER=root
CONTROL_PLANE_IPS="master02"
for host in ${CONTROL_PLANE_IPS}; do
    ssh "${USER}"@$host "mkdir -p /etc/kubernetes/pki/etcd"
    scp /etc/kubernetes/pki/ca.* "${USER}"@$host:/etc/kubernetes/pki/
    scp /etc/kubernetes/pki/sa.* "${USER}"@$host:/etc/kubernetes/pki/
    scp /etc/kubernetes/pki/front-proxy-ca.* "${USER}"@$host:/etc/kubernetes/pki/
    scp /etc/kubernetes/pki/etcd/ca.* "${USER}"@$host:/etc/kubernetes/pki/etcd/
    scp /etc/kubernetes/admin.conf "${USER}"@$host:/etc/kubernetes/
done


#拷贝正式至master03节点
USER=root
CONTROL_PLANE_IPS="master03"
for host in ${CONTROL_PLANE_IPS}; do
    ssh "${USER}"@$host "mkdir -p /etc/kubernetes/pki/etcd"
    scp /etc/kubernetes/pki/ca.* "${USER}"@$host:/etc/kubernetes/pki/
    scp /etc/kubernetes/pki/sa.* "${USER}"@$host:/etc/kubernetes/pki/
    scp /etc/kubernetes/pki/front-proxy-ca.* "${USER}"@$host:/etc/kubernetes/pki/
    scp /etc/kubernetes/pki/etcd/ca.* "${USER}"@$host:/etc/kubernetes/pki/etcd/
    scp /etc/kubernetes/admin.conf "${USER}"@$host:/etc/kubernetes/
done

在master02上执行，注意注意--experimental-control-plane参数

[root@master02 ~]# kubeadm join 172.16.4.231:8443 --token abcdef.0123456789abcdef \
>     --discovery-token-ca-cert-hash sha256:0ca0a5fd28409faecba5d2f21aeb010a945a5dae42023fe361424d621708edc1 \
>     --experimental-control-plane
[preflight] Running pre-flight checks
	[WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/
[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -oyaml'
[preflight] Running pre-flight checks before initializing the new control plane instance
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [master02 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.209.0.1 172.16.4.130 172.16.4.231]
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [master02 localhost] and IPs [172.16.4.130 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [master02 localhost] and IPs [172.16.4.130 127.0.0.1 ::1]
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "front-proxy-client" certificate and key
[certs] Valid certificates and keys now exist in "/etc/kubernetes/pki"
[certs] Using the existing "sa" key
[kubeconfig] Generating kubeconfig files
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
[kubeconfig] Using existing kubeconfig file: "/etc/kubernetes/admin.conf"
[kubeconfig] Writing "controller-manager.conf" kubeconfig file
[kubeconfig] Writing "scheduler.conf" kubeconfig file
[control-plane] Using manifest folder "/etc/kubernetes/manifests"
[control-plane] Creating static Pod manifest for "kube-apiserver"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[check-etcd] Checking that the etcd cluster is healthy
[kubelet-start] Downloading configuration for the kubelet from the "kubelet-config-1.14" ConfigMap in the kube-system namespace
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Activating the kubelet service
[kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap...
[etcd] Announced new etcd member joining to the existing etcd cluster
[etcd] Wrote Static Pod manifest for a local etcd member to "/etc/kubernetes/manifests/etcd.yaml"
[etcd] Waiting for the new etcd member to join the cluster. This can take up to 40s
[upload-config] storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[mark-control-plane] Marking the node master02 as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node master02 as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]

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.
* Control plane (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.

注意**：token有效期是有限的，如果旧的token过期，可以使用kubeadm token create --print-join-command重新创建一条token。

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

在master03上执行，注意注意--experimental-control-plane参数

[root@master03 ~]# kubeadm join 172.16.4.231:8443 --token abcdef.0123456789abcdef \
>     --discovery-token-ca-cert-hash sha256:0ca0a5fd28409faecba5d2f21aeb010a945a5dae42023fe361424d621708edc1 \
>     --experimental-control-plane
[preflight] Running pre-flight checks
	[WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/
[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -oyaml'
[preflight] Running pre-flight checks before initializing the new control plane instance
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "front-proxy-client" certificate and key
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [master03 localhost] and IPs [172.16.4.133 127.0.0.1 ::1]
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [master03 localhost] and IPs [172.16.4.133 127.0.0.1 ::1]
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [master03 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.209.0.1 172.16.4.133 172.16.4.231]
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Valid certificates and keys now exist in "/etc/kubernetes/pki"
[certs] Using the existing "sa" key
[kubeconfig] Generating kubeconfig files
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
[kubeconfig] Using existing kubeconfig file: "/etc/kubernetes/admin.conf"
[kubeconfig] Writing "controller-manager.conf" kubeconfig file
[kubeconfig] Writing "scheduler.conf" kubeconfig file
[control-plane] Using manifest folder "/etc/kubernetes/manifests"
[control-plane] Creating static Pod manifest for "kube-apiserver"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[check-etcd] Checking that the etcd cluster is healthy
[kubelet-start] Downloading configuration for the kubelet from the "kubelet-config-1.14" ConfigMap in the kube-system namespace
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Activating the kubelet service
[kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap...
[etcd] Announced new etcd member joining to the existing etcd cluster
[etcd] Wrote Static Pod manifest for a local etcd member to "/etc/kubernetes/manifests/etcd.yaml"
[etcd] Waiting for the new etcd member to join the cluster. This can take up to 40s
[upload-config] storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[mark-control-plane] Marking the node master03 as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node master03 as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]

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.
* Control plane (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.

[root@master03 ~]# mkdir -p $HOME/.kube \
> && cp -i /etc/kubernetes/admin.conf $HOME/.kube/config \
> && chown $(id -u):$(id -g) $HOME/.kube/config
[root@master03 ~]# kubectl get nodes
NAME       STATUS     ROLES    AGE     VERSION
master01   NotReady   master   15m     v1.14.2
master02   NotReady   master   3m40s   v1.14.2
master03   NotReady   master   2m1s    v1.14.2

8. node节点部署

在node01、node02执行,注意没有--experimental-control-plane参数

注意**：token有效期是有限的，如果旧的token过期，可以在master节点上使用kubeadm token create --print-join-command重新创建一条token。

在node01和node02上执行下面这条命令

kubeadm join 172.16.4.231:8443 --token lwsk91.y2ywpq0y74wt03tb     --discovery-token-ca-cert-hash sha256:0ca0a5fd28409faecba5d2f21aeb010a945a5dae42023fe361424d621708edc1 

9. 部署网络插件calico

9.1 下载calico.yaml文件

wget -c https://docs.projectcalico.org/v3.6/getting-started/kubernetes/installation/hosted/kubernetes-datastore/calico-networking/1.7/calico.yaml

9.2 修改calico.yaml（根据实际情况配置）

修改CALICO_IPV4POOL_CIDR这个下面的vaule值，默认是192.168.0.0/16

        # The default IPv4 pool to create on startup if none exists. Pod IPs will be
        # chosen from this range. Changing this value after installation will have
        # no effect. This should fall within `--cluster-cidr`.
        - name: CALICO_IPV4POOL_CIDR
          value: "10.209.0.0/16"

9.3 执行kubectl apply -f calico.yaml

[root@master01 ~]# kubectl apply -f calico.yaml
configmap/calico-config created
customresourcedefinition.apiextensions.k8s.io/felixconfigurations.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/ipamblocks.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/blockaffinities.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/ipamhandles.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/ipamconfigs.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/bgppeers.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/bgpconfigurations.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/ippools.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/hostendpoints.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/clusterinformations.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/globalnetworkpolicies.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/globalnetworksets.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/networkpolicies.crd.projectcalico.org created
clusterrole.rbac.authorization.k8s.io/calico-kube-controllers created
clusterrolebinding.rbac.authorization.k8s.io/calico-kube-controllers created
clusterrole.rbac.authorization.k8s.io/calico-node created
clusterrolebinding.rbac.authorization.k8s.io/calico-node created
daemonset.extensions/calico-node created
serviceaccount/calico-node created
deployment.extensions/calico-kube-controllers created
serviceaccount/calico-kube-controllers created

9.4 查看节点状态

一开始没安装网络组件，是显示notReady的，装完cailco后就变成Ready，说明集群已就绪了，可以进行下一步验证集群是否搭建成功

[root@master01 ~]# kubectl get nodes
NAME       STATUS     ROLES    AGE   VERSION
master01   Ready      master   23h   v1.14.2
master02   Ready      master   22h   v1.14.2
master03   Ready      master   22h   v1.14.2
node01     NotReady   <none>   19m   v1.14.2
node03     NotReady   <none>   5s    v1.14.2

10. kube-proxy开启ipvs[单个master节点执行]

10.1 修改ConfigMap的kube-system/kube-proxy中的config.conf，mode: "ipvs"：

kubectl edit cm kube-proxy -n kube-system

10.2 之后重启各个节点上的kube-proxy pod：

[root@master01 ~]# kubectl get pod -n kube-system | grep kube-proxy | awk '{system("kubectl delete pod "$1" -n kube-system")}'
pod "kube-proxy-8fpjb" deleted
pod "kube-proxy-dqqxh" deleted
pod "kube-proxy-mxvz2" deleted
pod "kube-proxy-np9x9" deleted
pod "kube-proxy-rtzcn" deleted

10.3 查看kube-proxy pod状态

[root@master01 ~]# kubectl get pod -n kube-system | grep kube-proxy
kube-proxy-4fhpg                           1/1     Running   0          81s
kube-proxy-9f2x6                           1/1     Running   0          109s
kube-proxy-cxl5m                           1/1     Running   0          89s
kube-proxy-lvp9q                           1/1     Running   0          78s
kube-proxy-v4mg8                           1/1     Running   0          99s

10.4 查看是否开启了ipvs

日志中打印出了Using ipvs Proxier，说明ipvs模式已经开启

[root@master01 ~]# kubectl logs kube-proxy-4fhpg -n kube-system
I0705 07:53:05.254157       1 server_others.go:176] Using ipvs Proxier.
W0705 07:53:05.255130       1 proxier.go:380] clusterCIDR not specified, unable to distinguish between internal and external traffic
W0705 07:53:05.255181       1 proxier.go:386] IPVS scheduler not specified, use rr by default
I0705 07:53:05.255599       1 server.go:562] Version: v1.14.2
I0705 07:53:05.280930       1 conntrack.go:52] Setting nf_conntrack_max to 131072
I0705 07:53:05.281426       1 config.go:102] Starting endpoints config controller
I0705 07:53:05.281473       1 controller_utils.go:1027] Waiting for caches to sync for endpoints config controller
I0705 07:53:05.281523       1 config.go:202] Starting service config controller
I0705 07:53:05.281548       1 controller_utils.go:1027] Waiting for caches to sync for service config controller
I0705 07:53:05.381724       1 controller_utils.go:1034] Caches are synced for endpoints config controller
I0705 07:53:05.381772       1 controller_utils.go:1034] Caches are synced for service config controller

11. 查看ipvs状态

[root@master01 ~]# ipvsadm -L -n
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  10.209.0.1:443 rr
  -> 172.16.4.129:6443            Masq    1      0          0         
  -> 172.16.4.130:6443            Masq    1      0          0         
  -> 172.16.4.133:6443            Masq    1      0          0         
TCP  10.209.0.10:53 rr
  -> 10.209.59.193:53             Masq    1      0          0         
  -> 10.209.59.194:53             Masq    1      0          0         
TCP  10.209.0.10:9153 rr
  -> 10.209.59.193:9153           Masq    1      0          0         
  -> 10.209.59.194:9153           Masq    1      0          0         
UDP  10.209.0.10:53 rr
  -> 10.209.59.193:53             Masq    1      0          0         
  -> 10.209.59.194:53             Masq    1      0          0 

12. 测试一个运行一个容器

[root@master01 ~]# kubectl run nginx --image=nginx:1.14 --replicas=2
kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
deployment.apps/nginx created

12.1 查看nginx pod

[root@master01 ~]# kubectl get pods -o wide
NAME                     READY   STATUS    RESTARTS   AGE   IP               NODE     NOMINATED NODE   READINESS GATES
nginx-84b67f57c4-d9k8m   1/1     Running   0          59s   10.209.196.129   node01   <none>           <none>
nginx-84b67f57c4-zcrxn   1/1     Running   0          59s   10.209.186.193   node03   <none>           <none>

12.2 通过curl命令测试nginx

[root@master01 ~]# curl 10.209.196.129
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
    body {
        width: 35em;
        margin: 0 auto;
        font-family: Tahoma, Verdana, Arial, sans-serif;
    }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>

<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>

<p><em>Thank you for using nginx.</em></p>
</body>
</html>
[root@master01 ~]# curl 10.209.186.193
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
    body {
        width: 35em;
        margin: 0 auto;
        font-family: Tahoma, Verdana, Arial, sans-serif;
    }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>

<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>

<p><em>Thank you for using nginx.</em></p>
</body>
</html>

能显示出Welcome to nginx，说明pod运行正常，间接也说明集群可以正常使用

13. 测试dns

进入后执行nslookup kubernetes.default

[root@master01 ~]# kubectl run curl --image=radial/busyboxplus:curl -it
kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
If you don't see a command prompt, try pressing enter.
[ root@curl-66bdcf564-njcqk:/ ]$ nslookup kubernetes.default
Server:    10.209.0.10
Address 1: 10.209.0.10 kube-dns.kube-system.svc.cluster.local

Name:      kubernetes.default
Address 1: 10.209.0.1 kubernetes.default.svc.cluster.local    #能显示类似这样的输出，说明dns是okay的

至此kubernetes集群部署完成。

14.典型报错

14.1 镜像无法拉取报错

ct: connection timed out
  Warning  FailedCreatePodSandBox  3m44s (x17 over 28m)  kubelet, node01    Failed create pod sandbox: rpc error: code = Unknown desc = failed pulling image "k8s.gcr.io/pause:3.1": Error response from daemon: Get https://k8s.gcr.io/v2/: dial tcp 74.125.204.82:443: connect: connection timed out

解决办法

先去其他渠道找到对应的镜像，然后docker tag下

docker pull registry.cn-hangzhou.aliyuncs.com/openthings/k8s-gcr-io-pause:3.1

docker tag registry.cn-hangzhou.aliyuncs.com/openthings/k8s-gcr-io-pause:3.1 k8s.gcr.io/pause:3.1