kubeadm部署k8s:v1.16.3高可用集群

一、环境说明

cat  /etc/hosts

192.168.10.11  node1        #master1

192.168.10.14  node4        #master2

192.168.10.15  node5        #master3

备注：由于是在自己虚拟机操作，因此只部署了master节点，worker节点执行的操作我会一并写出，按照操作即可。

二、环境配置<master和worker执行>

 1、设置阿里云yum源（可选）

curl -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

rm -rf /var/cache/yum && yum makecache

2、安装依赖包

yum install -y epel-release conntrack ipvsadm ipset jq sysstat curl iptables libseccomp

3、关闭防火墙

systemctl stop firewalld && systemctl disable firewalld

iptables -F && iptables -X && iptables -F -t nat && iptables -X -t nat && iptables -P FORWARD ACCEPT

4、关闭SELinux

setenforce 0

sed -i "s/SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config

5、关闭 swap 分区

swapoff -a

sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab

6、加载内核模块

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

modprobe -- br_netfilter

EOF

chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules

7、设置内核参数

cat << EOF | tee /etc/sysctl.d/k8s.conf

net.bridge.bridge-nf-call-iptables=1

net.bridge.bridge-nf-call-ip6tables=1

net.ipv4.ip_forward=1

net.ipv4.tcp_tw_recycle=0

vm.swappiness=0

vm.overcommit_memory=1

vm.panic_on_oom=0

fs.inotify.max_user_watches=89100

fs.file-max=52706963

fs.nr_open=52706963

net.ipv6.conf.all.disable_ipv6=1

net.netfilter.nf_conntrack_max=2310720

EOF

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

 8、安装Docker

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

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

yum makecache fast

yum install -y docker-ce-18.09.6

systemctl start docker

systemctl enable docker

安装完成后配置启动时的命令，否则docker会将iptables FORWARD chain的默认策略设置为DROP

另外Kubeadm建议将systemd设置为cgroup驱动，所以还要修改daemon.json

sed -i "13i ExecStartPost=/usr/sbin/iptables -P FORWARD ACCEPT" /usr/lib/systemd/system/docker.service

tee /etc/docker/daemon.json <<-'EOF'

{  "exec-opts": ["native.cgroupdriver=systemd"]  }

EOF

systemctl daemon-reload

systemctl restart docker

 9、安装kubeadm和kubelet

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

yum makecache fast

yum install -y kubelet kubeadm kubectl

systemctl enable kubelet

vim /usr/lib/systemd/system/kubelet.service.d/10-kubeadm.conf

#设置kubelet的cgroup driver

KUBELET_KUBECONFIG_ARGS=--cgroup-driver=systemd

systemctl daemon-reload

systemctl restart kubelet.service

10、拉取所需镜像

kubeadm config images list | sed -e 's/^/docker pull /g' -e 's#k8s.gcr.io#registry.cn-hangzhou.aliyuncs.com/google_containers#g' | sh -x

docker images | grep registry.cn-hangzhou.aliyuncs.com/google_containers | awk '{print "docker tag",$1":"$2,$1":"$2}' | sed -e 's/registry.cn-hangzhou.aliyuncs.com\/google_containers/k8s.gcr.io/2' | sh -x

docker images | grep registry.cn-hangzhou.aliyuncs.com/google_containers | awk '{print "docker rmi """$1""":"""$2}' | sh -x

三、安装keepalived和haproxy<master执行>

    Kubernetes的高可用主要指的是控制平面的高可用，简单说就是有多套Master节点组件和Etcd组件，工作节点通过负载均衡连接到各Master。

将etcd与Master节点组件混布在一起：

Etcd混布方式：
    所需机器资源少
    部署简单，利于管理
    容易进行横向扩展
    风险大，一台宿主机挂了，master和etcd就都少了一套，集群冗余度受到的影响比较大。

    3.1master安装

yum install -y keepalived haproxy

    3.2修改haproxy配置文件：(三个节点都一致)

global
    log         127.0.0.1 local2
    chroot      /var/lib/haproxy
    pidfile     /var/run/haproxy.pid
    maxconn     4000
    user        haproxy
    group       haproxy
    daemon
    stats socket /var/lib/haproxy/stats
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
listen stats
    bind                 *:1080
    stats auth           admin:awesomePassword
    stats refresh        5s
    stats realm          HAProxy\ Statistics
    stats uri            /admin?stats
frontend kubernetes-apiserver
   mode  tcp
   bind  *:8443
   option   tcplog
   default_backend     kubernetes-apiserver
backend kubernetes-apiserver
    balance     roundrobin
    mode        tcp
    server  node1 192.168.10.11:6443 check inter 5000 fall 2 rise 2 weight 1
    server  node4 192.168.10.14:6443 check inter 5000 fall 2 rise 2 weight 1
    server  node5 192.168.10.15:6443 check inter 5000 fall 2 rise 2 weight 1

    3.3修改keepalived的配置文件

    节点一：

! Configuration File for keepalived
global_defs {
   router_id LVS_DEVEL
}
vrrp_script check_haproxy {
    script "/etc/keepalived/check_haproxy.sh"
    interval 3
    weight -2
    fall 10
    rise 2
}
vrrp_instance VI_1 {
    state MASTER
    interface ens33         #宿主机物理网卡名称
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.10.16      #VIP要与自己的IP在同一网段
    }
        track_script {
            check_haproxy
    }
}

    节点二：

! Configuration File for keepalived
global_defs {
   router_id LVS_DEVEL
}
vrrp_script check_haproxy {
    script "/etc/keepalived/check_haproxy.sh"
    interval 3
    weight -2
    fall 10
    rise 2
}
vrrp_instance VI_1 {
    state BACKUP
    interface ens33
    virtual_router_id 51
    priority 80
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.10.16
    }
        track_script {
            check_haproxy
    }
}

    节点三：

! Configuration File for keepalived
global_defs {
   router_id LVS_DEVEL
}
vrrp_script check_haproxy {
    script "/etc/keepalived/check_haproxy.sh"
    interval 3
    weight -2
    fall 10
    rise 2
}
vrrp_instance VI_1 {
    state BACKUP
    interface ens33
    virtual_router_id 51
    priority 60
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.10.16
    }
        track_script {
            check_haproxy
    }
}

    在三个master执行：

cat > /etc/keepalived/check_haproxy.sh <<EOF
#!/bin/bash
systemctl status haproxy > /dev/null
if [[ \$? != 0 ]];then
        echo "haproxy is down,close the keepalived"
        systemctl stop keepalived
fi
EOF
chmod +x /etc/keepalived/check_haproxy.sh
systemctl enable keepalived && systemctl start keepalived 
systemctl enable haproxy && systemctl start haproxy
systemctl status keepalived && systemctl status haproxy
#如果keepalived状态不是running，则从新执行
systemctl  restart  keepalived

    即可在master节点看到：

到此keepalived和haproxy准备完成。

四、初始化集群

kubeadm init \
  --kubernetes-version=v1.16.3 \
  --pod-network-cidr=10.244.0.0/16 \
  --apiserver-advertise-address=192.168.10.11 \
  --control-plane-endpoint 192.168.10.16:8443 --upload-certs

则表示初始化成功

    1.为需要使用kubectl的用户进行配置

mkdir -p $HOME/.kube

cp -i /etc/kubernetes/admin.conf $HOME/.kube/config

chown $(id -u):$(id -g) $HOME/.kube/config

    2.安装Pod Network

    安装canal网络插件

wget https://docs.projectcalico.org/v3.1/getting-started/kubernetes/installation/hosted/canal/rbac.yaml

wget https://docs.projectcalico.org/v3.1/getting-started/kubernetes/installation/hosted/canal/canal.yaml

这里需要修改canal.yaml文件中

修改为：

    3.然后部署：

看到所有状态都是running则部署成功

    4、加入其他的master节点

kubeadm join 192.168.10.16:8443 --token 4r7i1t.pu099ydf73ju2dq0 \
    --discovery-token-ca-cert-hash sha256:65547a2b5633ea663cf9edbde3a65c3d1eb4d0f932ac2c6c6fcaf77dcd86a55f \
    --control-plane --certificate-key e8aeb23b165bf87988b4b30a80635d35e45a14d958a10ec616190665c835dc6a

在任意节点执行：

kubectl  get  node

    5.进行测试master高可用：

    down掉master1

在其他节点查看

五、加入worker节点

kubeadm join 192.168.10.16:8443 --token 4r7i1t.pu099ydf73ju2dq0 \
    --discovery-token-ca-cert-hash sha256:65547a2b5633ea663cf9edbde3a65c3d1eb4d0f932ac2c6c6fcaf77dcd86a55f