目录
前言
运维kubernetes有些时日了，一直有想写一个关于k8s集群完整部署的文章，以记录自己的学习和成长历程，奈何懒作，一直未行动。现在终于动起来了，希望文章能给大家带来一些作用和启发。
架构
先看下基本架构：
环境
| 名称 | IP | 配置 |
|---|---|---|
| k8s-m | 192.168.238.146 | 2CPU,4GB内存 |
| k8s-n01 | 192.168.238.147 | 2CPU,2GB内存 |
| k8s-n02 | 192.168.238.148 | 2CPU,2GB内存 |
部署
准备工作
在所有主机上执行
- 关闭防火墙
systemctl stop firewalld
systemctl disable firewalld
- 关闭selinux
sed -i 's/enforcing/disabled/' /etc/selinux/config
- 关闭swap
swapoff -a # 临时关闭
sed -ri 's/.*swap.*/#&/' /etc/fstab #永久关闭
- 修改主机名称
hostnamectl set-hostname k8s-m
hostnamectl set-hostname k8s-n01
hostnamectl set-hostname k8s-n02
- 添加主机名与IP对应关系(记得设置主机名)：
cat /etc/hosts
192.168.238.146 k8s-m
192.168.238.147 k8s-n01
192.168.238.148 k8s-n02
- 将桥接的IPv4流量传递到iptables的链
cat > /etc/sysctl.d/k8s.conf << EOF
> net.bridge.bridge-nf-call-ip6tables = 1
> net.bridge.bridge-nf-call-iptables = 1
> EOF
sysctl --system
安装Docker/kubeadm/kubelet
在所有节点上执行
- 安装docker
yum install -y wget && wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo
yum list docker-ce --showduplicates | sort -r
yum -y install docker-ce-19.03.9
systemctl enable docker && systemctl start docker
- 安装kubeadm，kubelet，kubectl
添加yum源
cat > /etc/yum.repos.d/kubernetes.repo << EOF
[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
安装
yum install -y kubelet-1.19.0 kubeadm-1.19.0 kubectl-1.19.0
设置kubelet开机启动
systemctl enable kubelet
部署kubernetes
在master上执行
kubeadm init \
--apiserver-advertise-address=192.168.238.146 \
--image-repository registry.aliyuncs.com/google_containers \
--kubernetes-version v1.19.0 \
--service-cidr=10.1.0.0/16 \
--pod-network-cidr=10.244.0.0/16
提示：Your Kubernetes control-plane has initialized successfully! 表明已经初始化成功，接下来进行后续操作。
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
添加节点，在节点上执行命令
kubeadm join 192.168.238.146:6443 --token niulk2.21qj3qsxm0xkdjxy \
--discovery-token-ca-cert-hash sha256:8aeb688e1572d72c76c57faba593d7e8bb3f30e0e0ada900ae9f0e872d0bf038
查看节点
kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-m NotReady master 3m42s v1.19.0
k8s-n01 NotReady <none> 69s v1.19.0
k8s-n02 NotReady <none> 39s v1.19.0
安装flannel网络组件
地址：https://raw.githubusercontent.com/flannel-io/flannel/master/Documentation/kube-flannel.yml
可能需要*，展现各位神通的时候到了。
安装flannel
kubectl apply -f kube-flannel.yaml
podsecuritypolicy.policy/psp.flannel.unprivileged created
clusterrole.rbac.authorization.k8s.io/flannel created
clusterrolebinding.rbac.authorization.k8s.io/flannel created
serviceaccount/flannel created
configmap/kube-flannel-cfg created
daemonset.apps/kube-flannel-ds created
查看flannel状态
kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
...
kube-flannel-ds-5dn86 1/1 Running 0 57s
kube-flannel-ds-ddwjx 1/1 Running 0 57s
kube-flannel-ds-zjv2n 1/1 Running 0 57s
...
再次查看节点状态,已经变成ready
kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-m Ready master 12m v1.19.0
k8s-n01 Ready <none> 9m52s v1.19.0
k8s-n02 Ready <none> 9m22s v1.19.0
查看cs，发现controller-manager、scheduler状态为Unhealthy
kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME STATUS MESSAGE ERROR
controller-manager Unhealthy Get "http://127.0.0.1:10252/healthz": dial tcp 127.0.0.1:10252: connect: connection refused
scheduler Unhealthy Get "http://127.0.0.1:10251/healthz": dial tcp 127.0.0.1:10251: connect: connection refused
etcd-0 Healthy {"health":"true"}
通过修改对应yaml文件解决
cd /etc/kubernetes/manifests/
vi kube-controller-manager.yaml
# - --port=0 将其注释掉
vi kube-scheduler.yaml
# - --port=0 将其注释掉
重启kubelet后，再次查看
systemctl restart kubelet
kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME STATUS MESSAGE ERROR
controller-manager Healthy ok
scheduler Healthy ok
etcd-0 Healthy {"health":"true"}
部署 Dashboard
地址：https://raw.githubusercontent.com/kubernetes/dashboard/v2.3.1/aio/deploy/recommended.yaml
git地址：https://github.com/kubernetes/dashboard
修改下载的yaml，因目前条件限制，暂时采用nodePort方式暴露服务
vi k8s-dashboard.yaml
...
kind: Service
apiVersion: v1
metadata:
labels:
k8s-app: kubernetes-dashboard
name: kubernetes-dashboard
namespace: kubernetes-dashboard
spec:
type: NodePort
ports:
- port: 443
targetPort: 8443
nodePort: 32080
selector:
k8s-app: kubernetes-dashboard
...
部署
kubectl apply -f k8s-dashboard.yaml
kubectl get pods --all-namespaces
...
kubernetes-dashboard dashboard-metrics-scraper-85cff7954d-xqff6 1/1 Running 0 3m11s
kubernetes-dashboard kubernetes-dashboard-658485d5c7-kjxjt 1/1 Running 0 3m11s
kubectl get svc --all-namespaces
...
kubernetes-dashboard dashboard-metrics-scraper ClusterIP 10.1.136.196 <none> 8000/TCP 3m54s
kubernetes-dashboard kubernetes-dashboard NodePort 10.1.92.105 <none> 443:32080/TCP 3m54s
访问 https://192.168.238.146:32080/#/login
配置使用kubeonfig登录
# 创建dashboard管理用户
kubectl create serviceaccount dashboard-admin -n kube-system
# 绑定用户为集群管理用户,也可绑定为普通角色
kubectl create clusterrolebinding dashboard-cluster-admin --clusterrole=cluster-admin --serviceaccount=kube-system:dashboard-admin
# 获取tocken
kubectl get secret -n kube-system | grep dashboard-admin
kubectl describe secret dashboard-admin-token-hbsbk -n kube-system
此时，可以使用token登录，但我想通过kubeonfig登录。继续看如何生成kubeconfig
DASH_TOCKEN=$(kubectl get secret dashboard-admin-token-hbsbk -n kube-system -o jsonpath={.data.token}|base64 -d)
kubectl config set-cluster kubernetes --server=192.168.238.146:6443 --kubeconfig=/root/dashbord-admin.conf
kubectl config set-credentials dashboard-admin --token=$DASH_TOCKEN --kubeconfig=/root/dashbord-admin.conf
kubectl config set-context dashboard-admin@kubernetes --cluster=kubernetes --user=dashboard-admin --kubeconfig=/root/dashbord-admin.conf
kubectl config use-context dashboard-admin@kubernetes --kubeconfig=/root/dashbord-admin.conf
将刚才的dashbord-admin.conf文件下载到本地,选择文件，点击登录。
登录成功后
完成以上安装，才只是万里长征第一步，请关注后续章节。