一、环境准备
2台主机都要安装 docker Centos7 安装 docker_一直被模仿，从未被超越-CSDN博客
master 192.168.2.100
node1 192.168.2.101
node2 192.168.2.102
1、修改 master 主机名 及 host
hostnamectl set-hostname master
cat <<EOF >> /etc/hosts
master 192.168.2.100
node1 192.168.2.101
node2 192.168.2.102
EOF
2、关闭 selinux 及防火墙
sed -i "s/SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config
systemctl stop firewalld && systemctl disable firewalld
3、禁用swap
# 临时
swapoff -a
# 永久，打开/etc/fstab注释掉swap那一行
sed -i 's/.*swap.*/#&/' /etc/fstab
4、修改网桥过滤及地址转发
cat <<EOF > /etc/sysctl.d/k8s.conf
vm.swappiness = 0
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
EOF
# 加载
modprobe br_netfilter
# 生效
sysctl -p /etc/sysctl.d/k8s.conf
5、修改Cgroup Driver
# 消除告警
cat <<EOF > /etc/docker/daemon.json
{
"registry-mirrors": ["http://hub-mirror.c.163.com"],
"exec-opts": ["native.cgroupdriver=systemd"]
}
EOF
# 重启生效
systemctl restart docker
6、开启 IPVS
yum install ipset ipvsadm -y
cat <<EOF > /etc/sysconfig/modules/ipvs.modules
#/bin/bash
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
EOF
chmod +x /etc/sysconfig/modules/ipvs.modules
bash /etc/sysconfig/modules/ipvs.modules
# 查看
lsmod | grep -e ip_vs -e nf_conntrack_ipv4
7、设置 kubenetes 源
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
８、安装
# 查看版本
yum list kubelet --showduplicates | sort -r
# 安装指定版本
yum install -y kubelet-1.17.2 kubeadm-1.17.2 kubectl-1.17.2
- kubelet 运行在集群所有节点上，用于启动Pod和容器等对象的工具
- kubeadm 用于初始化集群，启动集群的命令工具
- kubectl 用于和集群通信的命令行，通过kubectl可以部署和管理应用，查看各种资源，创建、删除和更新各种组件
９、启动
启动 kubelet 之后 我们查看一下 kubelet 状态是未启动状态，查看原因发现是 “/var/lib/kubelet/config.yaml”文件不存在，这里可以暂时先不用处理，当kubeadm init 之后会创建此文件
# 启动
systemctl start kubelet && systemctl enable kubelet
# 查看状态
systemctl status kubelet
kubelet.service - kubelet: The Kubernetes Node Agent
Loaded: loaded (/usr/lib/systemd/system/kubelet.service; enabled; vendor preset: disabled)
Drop-In: /usr/lib/systemd/system/kubelet.service.d
└─10-kubeadm.conf
Active: activating (auto-restart) (Result: exit-code) since 日 2019-03-31 16:18:55 CST; 7s ago
Docs: https://kubernetes.io/docs/
Process: 4564 ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_CONFIG_ARGS $KUBELET_KUBEADM_ARGS $KUBELET_EXTRA_ARGS (code=exited, status=255)
Main PID: 4564 (code=exited, status=255)
二、master 安装
1、初始化 k8s
kubeadm init \
--image-repository registry.aliyuncs.com/google_containers \
--kubernetes-version v1.17.2 \
--apiserver-advertise-address 192.168.2.100 \
--pod-network-cidr=10.244.0.0/16
--image-repository：指定镜像源
--kubernetes-version：指定 k8s 版本，要跟上面安装的保持一致
--apiserver-advertise-address：指定master的interface
--pod-network-cidr：指定Pod网络的范围，这里使用flannel网络方案
成功后，自动创建了 "/var/lib/kubelet/config.yaml"
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/
Then you can join any number of worker nodes by running the following on each as root:
# 记录这行,后面 node 节点加入集群会用到
kubeadm join 192.168.1.111:6443 --token 8a1x7a.84gh8ghc9c3z7uak \
--discovery-token-ca-cert-hash sha256:16ebeae9143006938c81126050f8fc8527d2a6b1c4991d07b9282f47cf4203d6
2、加载环境变量
mkdir -p $HOME/.kube
cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
chown $(id -u):$(id -g) $HOME/.kube/config
3、查看组件状态
[root@master ~]# kubectl get cs
NAME STATUS MESSAGE ERROR
scheduler Healthy ok
etcd-0 Healthy {"health":"true"}
controller-manager Healthy ok
4、查看 node
# 状态为 NotReady，因为没有安装 pod 网络
[root@mysql-master1 ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master NotReady master 105s v1.17.2
5、安装 pod 网络
k8s cluster 工作必须安装pod网络，否则pod之间无法通信，k8s支持多种方案，这里选择flannel
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
6、查看 pod 状态，确保当前 pod 都为 Running
# 查看所有命名空间 pod
[root@master ~]# kubectl get pod --all-namespaces -o wide
NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
kube-system coredns-9d85f5447-qghnb 1/1 Running 1 63m 10.244.0.5 master1 <none> <none>
kube-system coredns-9d85f5447-xqsl2 1/1 Running 1 63m 10.244.0.4 master1 <none> <none>
kube-system etcd-master1 1/1 Running 1 63m 192.168.2.100 master1 <none> <none>
kube-system kube-apiserver-master1 1/1 Running 1 63m 192.168.2.100 master1 <none> <none>
kube-system kube-controller-manager-master1 1/1 Running 1 63m 192.168.2.100 master1 <none> <none>
kube-system kube-flannel-ds-amd64-52n6m 1/1 Running 0 9m9s 192.168.2.100 master1 <none> <none>
kube-system kube-proxy-xk7gq 1/1 Running 1 63m 192.168.2.100 master1 <none> <none>
kube-system kube-scheduler-master1 1/1 Running 1 63m 192.168.2.100 master1 <none> <none>
7、查看 node，status 为 Ready
[root@master1 ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master Ready master 66m v1.17.2
8、安装成功
三、 node 节点 安装
按第一步上面的环境配置，在 node1，node2 节点 安装 k8s，注意要修改对应的主机名及hosts
1、加入集群
# 如果忘记，可以在 master 节点查看
kubeadm token list
# 如果过期，可以在 master 节点重新生成
kubeadm token create --print-join-command
# 显示，在 node1 node2 节点上面分别执行
kubeadm join 192.168.1.111:6443 --token j88bsx.o0ugzfnxqdl5s58e \
--discovery-token-ca-cert-hash sha256:16ebeae9143006938c81126050f8fc8527d2a6b1c4991d07b9282f47cf4203d6
2、查看 节点 网络
# node1 节点分配的子网段是 10.244.1.0/24
[root@node1 ~]# ifconfig | grep -A 6 flannel
flannel.1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1450
inet 10.244.1.0 netmask 255.255.255.255 broadcast 10.244.1.0
inet6 fe80::d4ce:d0ff:fed9:4dd3 prefixlen 64 scopeid 0x20<link>
ether d6:ce:d0:d9:4d:d3 txqueuelen 0 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
[root@node1 ~]#
# node2 节点分配的子网段是 10.244.2.0/24
[root@node2 ~]# ifconfig | grep -A 6 flannel
flannel.1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1450
inet 10.244.2.0 netmask 255.255.255.255 broadcast 10.244.2.0
inet6 fe80::8a3:8cff:fe4b:7692 prefixlen 64 scopeid 0x20<link>
ether 0a:a3:8c:4b:76:92 txqueuelen 0 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
3、查看 node
[root@master ~]# kubectl get nodes
# 显示
NAME STATUS ROLES AGE VERSION
master Ready master 23m v1.17.2
node1 Ready <none> 18m v1.17.2
node2 Ready <none> 15m v1.17.2
4、查看 pod
[root@master ~]# kubectl get pod --all-namespaces -o wide
NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
kube-system coredns-9d85f5447-7wvwr 1/1 Running 0 17m 10.244.0.2 master <none> <none>
kube-system coredns-9d85f5447-jm7t8 1/1 Running 0 17m 10.244.0.3 master <none> <none>
kube-system etcd-master 1/1 Running 0 18m 192.168.2.100 master <none> <none>
kube-system kube-apiserver-master 1/1 Running 0 18m 192.168.2.100 master <none> <none>
kube-system kube-controller-manager-master 1/1 Running 0 18m 192.168.2.100 master <none> <none>
kube-system kube-flannel-ds-8qnct 1/1 Running 0 16m 192.168.2.100 master <none> <none>
kube-system kube-flannel-ds-bnljr 1/1 Running 1 9m54s 192.168.2.102 node2 <none> <none>
kube-system kube-flannel-ds-txw2v 1/1 Running 0 13m 192.168.2.101 node1 <none> <none>
kube-system kube-proxy-998w5 1/1 Running 0 17m 192.168.2.100 master <none> <none>
kube-system kube-proxy-cddmq 1/1 Running 0 13m 192.168.2.101 node1 <none> <none>
kube-system kube-proxy-dkc82 1/1 Running 0 9m54s 192.168.2.102 node2 <none> <none>
kube-system kube-scheduler-master 1/1 Running 0 18m 192.168.2.100 master <none> <none>
５、如何删除 node
# 删除 node2 节点
[root@master1 ~]# kubectl delete node node2
# 重置
[root@node2 ~]# kubeadm reset
# 重新加入
[root@node2 ~]# kubeadm join
四、配置 IPVS
1、修改 kube-proxy 模式
[root@master ~]# kubectl edit cm kube-proxy -n kube-system
apiVersion: v1
data:
config.conf: |-
---
metricsBindAddress: ""
mode: "ipvs" # 修改成ipvs
nodePortAddresses: null
oomScoreAdj: null
portRange: ""
udpIdleTimeout: 0s
winkernel:
enableDSR: false
2、重启
[root@master ~]# kubectl delete pod \
$(kubectl get pod -n kube-system | grep kube-proxy | \
awk '{print $1}') -n kube-system
3、查看
[root@master ~]# kubectl logs kube-proxy-k9lwp -n kube-system
I1025 12:20:39.081445 1 node.go:135] Successfully retrieved node IP: 192.168.2.100
I1025 12:20:39.081559 1 server_others.go:172] Using ipvs Proxier. # 已经使用 ipvs
W1025 12:20:39.081791 1 proxier.go:420] IPVS scheduler not specified, use rr by default
I1025 12:20:39.081985 1 server.go:571] Version: v1.17.2
I1025 12:20:39.082522 1 conntrack.go:52] Setting nf_conntrack_max to 131072
I1025 12:20:39.085741 1 config.go:313] Starting service config controller
I1025 12:20:39.089351 1 shared_informer.go:197] Waiting for caches to sync for service config
I1025 12:20:39.087017 1 config.go:131] Starting endpoints config controller
I1025 12:20:39.089388 1 shared_informer.go:197] Waiting for caches to sync for endpoints config
I1025 12:20:39.189968 1 shared_informer.go:204] Caches are synced for endpoints config
I1025 12:20:39.190031 1 shared_informer.go:204] Caches are synced for service config
