目录

文章目录

  • 目录
  • Kubernetes 在生产环境中架构
  • 高可用集群部署拓扑
  • 1、网络代理配置
  • 2、Load Balancer 环境准备
  • 3、Kubernetes Cluster 环境准备
  • 安装 Container Runtime
  • 安装 kubeadm、kubelet 和 kubectl
  • 4、初始化 Master 主控制平面节点
  • kubeadm init 的工作流
  • 执行初始化
  • (可选)清理或重新进行初始化
  • 5、添加 Master 冗余控制平面节点
  • 6、添加 Node 工作负载节点
  • 7、安装 CNI 网络插件
  • 8、安装 Metrics Server
  • Kubernetes Metrics Server
  • 启用 API Aggregator
  • 安装 Metrics Server
  • 9、安装 Dashboard GUI
  • 10、访问 Dashboard UI
  • 11、通过 NFS 实现持久化存储
  • NFS Server 安装
  • NFS Client 挂载
  • Kubernetes 部署 nfs-client-provisioner

Kubernetes 在生产环境中架构

kubespray 部署高可用集群 kubeadm高可用_kubespray 部署高可用集群

  1. Client 层:外部用户、客户端等;

  2. 服务访问层:Traefik、Kong APIGW 等 Ingress。外部客户端访问 Kubernetes Cluster 内部的 Service 时,使用 Ingress 支持的服务发现、负载均衡、路由规则定义来实现。此外,应当实现 Ingress 的 HA。
  3. kubespray 部署高可用集群 kubeadm高可用_云原生_02

  4. 业务应用层:即基于 Kubernetes 之上构建和运行的企业业务应用。
  1. 镜像管理:使用 Harbor 私有镜像仓库服务;
  2. 日志管理:使用 ELK Stack;
  3. 监控告警管理:使用 Prometheus 和 Grafana;
  4. 微服务架构:使用 Istio 的 Service Mesh 方案,或者使用 APIGW;
  5. DevOps:使用 Gitlab、Jenkins 等 CI/CD 工具;
  6. 单体应用:无状态类服务使用 Deployment,有状态类服务则使用 Statefulset,如果关联的服务较多且复杂则使用 Helm。
  7. 规划好 Namespace:应当做到每个 Namespace 专属用于某类型的应用,例如:monitor namespace 用于统一管理监控告警、日志管理方面的 pod、service、pvc、ingress 等资源对象。
  1. 基础设施层:即由 Kubernetes、Calico SDN、Ceph SDS 或 NFS 等系统组成的基础设施服务。

高可用集群部署拓扑

官方文档:https://kubernetes.io/zh/docs/setup/production-environment/

  • 基础设施:OpenStack
  • 虚拟机集群:3 Master、2 Node、2 Load Balancer
  • 计算资源:x86-64 processor、2CPU、2GB RAM、20GB free disk space
  • 操作系统:CentOS 7.x+
  • 版本:Kubernetes 1.18.14
  • Container Runtime:Docker

kubespray 部署高可用集群 kubeadm高可用_kubernetes_03

1、网络代理配置

需要对 HTTP/S Proxy 和 No Proxy 进行精心的配置,否则要么下不下来软件,要么出现网络连通性的错误。

export https_proxy=http://{proxy_ip}:7890 http_proxy=http://{proxy_ip}:7890 all_proxy=socks5://{proxy_ip}:7890 no_proxy=localhost,127.0.0.1,{apiserver_endpoint_ip},{k8s_mgmt_network_ip_pool},{pod_network_ip_pool},{service_network_ip_pool}

2、Load Balancer 环境准备

基于 OpenStack Octavia LBaaS 来提供 HA Load Balancer,也可以手动的配置 keepalived and haproxy(https://github.com/kubernetes/kubeadm/blob/master/docs/ha-considerations.md#options-for-software-load-balancing)。


  • VIP 选择 kube-mgmt-subnet
  • kubespray 部署高可用集群 kubeadm高可用_kubespray 部署高可用集群_04


  • Listener 选择 TCP :6443 Socket(kube-apiserver 的监听端口)
  • kubespray 部署高可用集群 kubeadm高可用_docker_05


  • Members 选择 3 个 k8s-master
  • kubespray 部署高可用集群 kubeadm高可用_kubespray 部署高可用集群_06


  • Monitor 同样选择 TCP :6443 Socket
  • kubespray 部署高可用集群 kubeadm高可用_云原生_07

注意:创建好 Load Balancer 之后,首先要测试一下 TCP 反向代理运行正常。由于 apiserver 现在尚未运行,所以预期会出现一个连接拒绝错误。在我们初始化了第一个控制平面节点之后,要记得再次进行测试。

# nc -v LOAD_BALANCER_IP PORT
nc -v 192.168.0.100 6443

3、Kubernetes Cluster 环境准备

注意:在所有节点上执行以下操作。

  • 添加全节点的 Hostname 解析。
# vi /etc/hosts

192.168.0.100 kube-apiserver-endpoint
192.168.0.148 k8s-master-1
192.168.0.112 k8s-master-2
192.168.0.193 k8s-master-3
192.168.0.208 k8s-node-1
192.168.0.174 k8s-node-2
  • 开启全节点之间的 SSH 免密登录。
  • 禁用 Swap 交换分区,为了保证 kubelet 正常工作。
  • 确保 iptables 工具不使用 nftables 后端,nftables 后端与当前的 kubeadm 软件包不兼容,它会导致重复的防火墙规则并破坏 kube-proxy。
  • 确保节点之间的网络联通性。
  • 关闭 SELinux,为了允许容器访问主机的文件系统。
# 将 SELinux 设置为 permissive 模式(相当于将其禁用)
setenforce 0
sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config
  • 在 RHEL/CentOS 7 上为了保证 kube-proxy 控制的数据流量必须进过 iptables 的处理来进行本地路由,所以要确保 sysctl 配置中的 net.bridge.bridge-nf-call-iptables 被设置为 1。
# 确保加载了 br_netfilter 模块。
modprobe br_netfilter
lsmod | grep br_netfilter

# 确保 sysctl 配置,将 Bridge 的 IPv4 流量传递到 iptables 的 Chain(链)
cat <<EOF >  /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl --system
  • 安装基础依赖软件:
yum install ebtables ethtool ipvsadm -y

安装 Container Runtime

注意:当 Linux 使用 systemd 时,会创建一个 cgroup,此时需要保证 Container Runtime、kubelet 和 systemd 使用的是同一个 cgroup,否则会出现不可预测的问题。为此,我们需要将 Container Runtime、kubelet 配置成使用 systemd 来作为 cgroup 驱动,以此使系统更为稳定。

对于 Docker 而言,设置 native.cgroupdriver=systemd 选项即可。

  • 安装
# 安装依赖包
sudo yum install -y yum-utils device-mapper-persistent-data lvm2

# 新增 Docker 仓库
sudo yum-config-manager --add-repo \
  https://download.docker.com/linux/centos/docker-ce.repo

# 安装 Docker CE
sudo yum update -y && sudo yum install -y \
  containerd.io-1.2.13 \
  docker-ce-19.03.11 \
  docker-ce-cli-19.03.11
  • 配置
# 创建 /etc/docker 目录
sudo mkdir /etc/docker

# 设置 Docker daemon
cat <<EOF | sudo tee /etc/docker/daemon.json
{
  "exec-opts": ["native.cgroupdriver=systemd"],
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "100m"
  },
  "storage-driver": "overlay2",
  "storage-opts": [
    "overlay2.override_kernel_check=true"
  ]
}
EOF
  • 重启
# Create /etc/systemd/system/docker.service.d
sudo mkdir -p /etc/systemd/system/docker.service.d

# 重启 Docker
sudo systemctl daemon-reload
sudo systemctl restart docker
sudo systemctl enable docker

sudo systemctl status docker

安装 kubeadm、kubelet 和 kubectl

注意:kubeadm 是 Kubernetes Cluster 的部署工具,但 kubeadm 不能用于安装、管理 kubelet 或 kubectl,所以我们需要收到安装它们,并且确保三者的版本仓库是一致的。

  • 更新 Kubernetes YUM 仓库
cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
EOF
  • 安装
# 查询版本
$ yum list kubelet kubeadm kubectl --showduplicates | grep 1.18.14 | sort -r
kubelet.x86_64                       1.18.14-0                       kubernetes
kubectl.x86_64                       1.18.14-0                       kubernetes
kubeadm.x86_64                       1.18.14-0                       kubernetes

# 安装指定版本
yum install -y kubelet-1.18.14 kubeadm-1.18.14 kubectl-1.18.14 --disableexcludes=kubernetes

# 确定版本一致
$ kubeadm version
kubeadm version: &version.Info{Major:"1", Minor:"18", GitVersion:"v1.18.14", GitCommit:"89182bdd065fbcaffefec691908a739d161efc03", GitTreeState:"clean", BuildDate:"2020-12-18T12:08:45Z", GoVersion:"go1.13.15", Compiler:"gc", Platform:"linux/amd64"}

$ kubectl version --client
Client Version: version.Info{Major:"1", Minor:"18", GitVersion:"v1.18.14", GitCommit:"89182bdd065fbcaffefec691908a739d161efc03", GitTreeState:"clean", BuildDate:"2020-12-18T12:11:25Z", GoVersion:"go1.13.15", Compiler:"gc", Platform:"linux/amd64"}

$ kubelet --version
Kubernetes v1.18.14
  • 配置:上面我们提到过,需要将 Container Runtime、kubelet 配置成使用 systemd 来作为 cgroup 驱动,以此使系统更为稳定。
# vi /etc/sysconfig/kubelet
KUBELET_EXTRA_ARGS=--cgroup-driver=systemd
  • 启动
$ systemctl daemon-reload
$ systemctl restart kubelet
$ systemctl enable --now kubelet
$ systemctl status kubelet

注意:kubelet.sercice 每隔几秒就会重启一次,循环等待 kubeadm 的指令。

4、初始化 Master 主控制平面节点

kubeadm init 的工作流

kubeadm init 命令通过执行下列步骤来启动一个 Kubernetes Master:

  1. 预检测系统状态:当出现 ERROR 时就退出 kubeadm,除非问题得到解决或者显式指定了 --ignore-preflight-errors=<错误列表> 参数。此外,也会出现 WARNING。
  2. 生成一个自签名的 CA 证书来为每个系统组件建立身份标识:可以显式指定 --cert-dir CA 中心目录(默认为 /etc/kubernetes/pki),在该目录下方式 CA 证书、密钥等文件。API Server 证书将为任何 --apiserver-cert-extra-sans 参数值提供附加的 SAN 条目,必要时将其小写。
  3. 将 kubeconfig 文件写入 /etc/kubernetes/ 目录:以便 kubelet、Controller Manager 和 Scheduler 用来连接到 API Server,它们都有自己的身份标识,同时生成一个名为 admin.conf 的独立的 kubeconfig 文件,用于管理操作。
  4. 为 API Server、Controller Manager 和 Scheduler 生成 static Pod 的清单文件:存放在 /etc/kubernetes/manifests 下,kubelet 会轮训监视这个目录,在启动 Kubernetes 时用于创建系统组件的 Pod。假使没有提供一个外部的 etcd 服务的话,也会为 etcd 生成一份额外的 static Pod 清单文件。

待 Master 的 static Pods 都运行正常后,kubeadm init 的工作流程才会继续往下执行。

  1. 对 Master 使用 Labels 和 Stain mark(污点标记):以此隔离生产工作负载不会调度到 Master 上。
  2. 生成 Token:将来其他的 Node 可使用该 Token 向 Master 注册自己。也可以显式指定 --token 提供 Token String。
  3. 为了使 Node 能够遵照启动引导令牌(Bootstrap Tokens)TLS 启动引导(TLS bootstrapping)这两份文档中描述的机制加入到 Cluster 中,kubeadm 会执行所有的必要配置:
  1. 创建一个 ConfigMap 提供添加 Node 到 Cluster 中所需的信息,并为该 ConfigMap 设置相关的 RBAC 访问规则。
  2. 允许启动引导令牌访问 CSR 签名 API。
  3. 配置自动签发新的 CSR 请求。
  1. 通过 API Server 安装一个 DNS 服务器(CoreDNS)和 kube-proxy:注意,尽管现在已经部署了 DNS 服务器,但直到安装 CNI 时才调度它。

执行初始化

注意 1:因为我们要部署高可用集群,所以必须使用选项 --control-plane-endpoint 指定 API Server 的 HA Endpoint。
注意 2:由于 kubeadm 默认从 k8s.grc.io 下载所需镜像,因此可以通过 --image-repository 指定阿里云的镜像仓库。
注意 3:如果显式指定 --upload-certs,则意味着在扩展冗余 Master 时,你必须要手动地将 CA 证书从主控制平面节点复制到将要加入的冗余控制平面节点上,推荐使用。

  • 初始化
kubeadm init \
  --control-plane-endpoint "192.168.0.100" \
  --kubernetes-version "1.18.14" \
  --pod-network-cidr "10.0.0.0/8" \
  --service-cidr "172.16.0.0/16" \
  --token "abcdef.0123456789abcdef" \
  --token-ttl "0" \
  --image-repository registry.aliyuncs.com/google_containers \
  --upload-certs

W1221 00:02:43.240309   10942 configset.go:202] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]
[init] Using Kubernetes version: v1.18.14
[preflight] Running pre-flight checks
[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] Starting the kubelet
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "ca" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [k8s-master-1 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [172.16.0.1 192.168.0.148 192.168.0.100]
[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 "etcd/ca" certificate and key
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [k8s-master-1 localhost] and IPs [192.168.0.148 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [k8s-master-1 localhost] and IPs [192.168.0.148 127.0.0.1 ::1]
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "sa" key and public key
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[kubeconfig] Writing "admin.conf" kubeconfig file
[kubeconfig] Writing "kubelet.conf" kubeconfig file
[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"
W1221 00:02:47.773223   10942 manifests.go:225] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[control-plane] Creating static Pod manifest for "kube-scheduler"
W1221 00:02:47.774303   10942 manifests.go:225] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[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 23.117265 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.18" in namespace kube-system with the configuration for the kubelets in the cluster
[upload-certs] Storing the certificates in Secret "kubeadm-certs" in the "kube-system" Namespace
[upload-certs] Using certificate key:
463868e92236803eb8fdeaa3d7b0ada67cf0f882c45974682c6ac2f20be1d544
[mark-control-plane] Marking the node k8s-master-1 as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node k8s-master-1 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 get nodes
[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
[kubelet-finalize] Updating "/etc/kubernetes/kubelet.conf" to point to a rotatable kubelet client certificate and key
[addons] Applied essential addon: CoreDNS
[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 the control-plane node running the following command on each as root:

  kubeadm join 192.168.0.100:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:88dc9773b5dfc0cde6082314a1a4a9bbdb6ddfd3f1f84a7113581a3b07e839e1 \
    --control-plane --certificate-key 463868e92236803eb8fdeaa3d7b0ada67cf0f882c45974682c6ac2f20be1d544

Please note that the certificate-key gives access to cluster sensitive data, keep it secret!
As a safeguard, uploaded-certs will be deleted in two hours; If necessary, you can use
"kubeadm init phase upload-certs --upload-certs" to reload certs afterward.

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

kubeadm join 192.168.0.100:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:88dc9773b5dfc0cde6082314a1a4a9bbdb6ddfd3f1f84a7113581a3b07e839e1
  • 查看 Pods:检查 Master 的组件是否齐全。
# 配置 kubectl
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

$ kubectl get pod -n kube-system
NAME                                   READY   STATUS    RESTARTS   AGE
coredns-7ff77c879f-fh9vb               0/1     Pending   0          23m
coredns-7ff77c879f-qmk7z               0/1     Pending   0          23m
etcd-k8s-master-1                      1/1     Running   0          24m
kube-apiserver-k8s-master-1            1/1     Running   0          24m
kube-controller-manager-k8s-master-1   1/1     Running   0          24m
kube-proxy-7hx55                       1/1     Running   0          23m
kube-scheduler-k8s-master-1            1/1     Running   0          24m
  • 查看 Images
$ docker images
REPOSITORY                                                        TAG                 IMAGE ID            CREATED             SIZE
registry.aliyuncs.com/google_containers/kube-proxy                v1.18.14            8e6bca1d4e68        2 days ago          117MB
registry.aliyuncs.com/google_containers/kube-apiserver            v1.18.14            f17e261f4c8a        2 days ago          173MB
registry.aliyuncs.com/google_containers/kube-controller-manager   v1.18.14            b734a959c6fb        2 days ago          162MB
registry.aliyuncs.com/google_containers/kube-scheduler            v1.18.14            95660d582e82        2 days ago          95.3MB
registry.aliyuncs.com/google_containers/pause                     3.2                 80d28bedfe5d        10 months ago       683kB
registry.aliyuncs.com/google_containers/coredns                   1.6.7               67da37a9a360        10 months ago       43.8MB
registry.aliyuncs.com/google_containers/etcd                      3.4.3-0             303ce5db0e90        14 months ago       288MB
  • 查看 Containers
$ docker ps -a
CONTAINER ID        IMAGE                                               COMMAND                  CREATED             STATUS              PORTS               NAMES
f9a068b890d7        8e6bca1d4e68                                        "/usr/local/bin/kube…"   2 minutes ago       Up 2 minutes                            k8s_kube-proxy_kube-proxy-7hx55_kube-system_aacb0da3-16ec-414c-b138-856e2b470bb9_0
3b6adfa0b1a5        registry.aliyuncs.com/google_containers/pause:3.2   "/pause"                 2 minutes ago       Up 2 minutes                            k8s_POD_kube-proxy-7hx55_kube-system_aacb0da3-16ec-414c-b138-856e2b470bb9_0
dcc47de63e50        f17e261f4c8a                                        "kube-apiserver --ad…"   3 minutes ago       Up 3 minutes                            k8s_kube-apiserver_kube-apiserver-k8s-master-1_kube-system_c693bd1fadf036d8e2e4df0afd49f062_0
53afb7fbe8c0        b734a959c6fb                                        "kube-controller-man…"   3 minutes ago       Up 3 minutes                            k8s_kube-controller-manager_kube-controller-manager-k8s-master-1_kube-system_f75424d466cd7197fb8095b0f59ea8d9_0
a4101a231c1b        303ce5db0e90                                        "etcd --advertise-cl…"   3 minutes ago       Up 3 minutes                            k8s_etcd_etcd-k8s-master-1_kube-system_f85e02734d6479f3bb3e468eea87fd3a_0
197f510ff6c5        95660d582e82                                        "kube-scheduler --au…"   3 minutes ago       Up 3 minutes                            k8s_kube-scheduler_kube-scheduler-k8s-master-1_kube-system_0213a889f9350758ac9847629f75db19_0
3a4590590093        registry.aliyuncs.com/google_containers/pause:3.2   "/pause"                 3 minutes ago       Up 3 minutes                            k8s_POD_kube-controller-manager-k8s-master-1_kube-system_f75424d466cd7197fb8095b0f59ea8d9_0
4bbdc99a7a68        registry.aliyuncs.com/google_containers/pause:3.2   "/pause"                 3 minutes ago       Up 3 minutes                            k8s_POD_kube-apiserver-k8s-master-1_kube-system_c693bd1fadf036d8e2e4df0afd49f062_0
19488127c269        registry.aliyuncs.com/google_containers/pause:3.2   "/pause"                 3 minutes ago       Up 3 minutes                            k8s_POD_etcd-k8s-master-1_kube-system_f85e02734d6479f3bb3e468eea87fd3a_0
e67d2f7a27b0        registry.aliyuncs.com/google_containers/pause:3.2   "/pause"                 3 minutes ago       Up 3 minutes                            k8s_POD_kube-scheduler-k8s-master-1_kube-system_0213a889f9350758ac9847629f75db19_0
  • 测试 API Server LB 是否正常
$ nc -v 192.168.0.100 6443
Connection to 192.168.0.100 port 6443 [tcp/sun-sr-https] succeeded!

注意:上述 Token 的过期时间是 24 小时,如果希望在 24 小时之后继续添加不通的节点,则需要重新生产 Token:

# 新建 Token
kubeadm token create
# output: 5didvk.d09sbcov8ph2amjw

# 新建 --discovery-token-ca-cert-hash
openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | \
   openssl dgst -sha256 -hex | sed 's/^.* //'
# output: 8cb2de97839780a412b93877f8507ad6c94f73add17d5d7058e91741c9d5ec78

(可选)清理或重新进行初始化

要再次运行 kubeadm init,你必须首先卸载集群,可以在 Master 上触发尽力而为的清理:

kubeadm reset

Reset 过程不会重置或清除 iptables 规则或 IPVS 表。如果你希望重置 iptables 或 IPVS,则必须手动进行:

iptables -F && iptables -t nat -F && iptables -t mangle -F && iptables -X
ipvsadm -C

根据需求调整参数,重新进行初始化:

kubeadm init <args>

或许,彻底删除节点:

kubectl delete node <node name>

5、添加 Master 冗余控制平面节点

在第一个 Master 初始化完毕之后,我们就可以继续添加冗余 Master 节点了。

  • 添加 k8s-master-2
kubeadm join 192.168.0.100:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:88dc9773b5dfc0cde6082314a1a4a9bbdb6ddfd3f1f84a7113581a3b07e839e1 \
    --control-plane --certificate-key 463868e92236803eb8fdeaa3d7b0ada67cf0f882c45974682c6ac2f20be1d544

[preflight] Running pre-flight checks
[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'
[download-certs] Downloading the certificates in Secret "kubeadm-certs" in the "kube-system" Namespace
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [k8s-master-2 localhost] and IPs [192.168.0.112 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [k8s-master-2 localhost] and IPs [192.168.0.112 127.0.0.1 ::1]
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [k8s-master-2 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [172.16.0.1 192.168.0.112 192.168.0.100]
[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"
[kubeconfig] Writing "admin.conf" kubeconfig file
[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"
W1221 00:30:18.978564   27668 manifests.go:225] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
W1221 00:30:18.986650   27668 manifests.go:225] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[control-plane] Creating static Pod manifest for "kube-scheduler"
W1221 00:30:18.987613   27668 manifests.go:225] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[check-etcd] Checking that the etcd cluster is healthy
[kubelet-start] Downloading configuration for the kubelet from the "kubelet-config-1.18" 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] Starting the kubelet
[kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap...
[etcd] Announced new etcd member joining to the existing etcd cluster
[etcd] Creating static Pod manifest for "etcd"
[etcd] Waiting for the new etcd member to join the cluster. This can take up to 40s
{"level":"warn","ts":"2020-12-21T00:30:34.018+0800","caller":"clientv3/retry_interceptor.go:61","msg":"retrying of unary invoker failed","target":"passthrough:///https://192.168.0.112:2379","attempt":0,"error":"rpc error: code = DeadlineExceeded desc = context deadline exceeded"}
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[mark-control-plane] Marking the node k8s-master-2 as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node k8s-master-2 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.
  • 添加 k8s-master-3
kubeadm join 192.168.0.100:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:88dc9773b5dfc0cde6082314a1a4a9bbdb6ddfd3f1f84a7113581a3b07e839e1 \
    --control-plane --certificate-key 463868e92236803eb8fdeaa3d7b0ada67cf0f882c45974682c6ac2f20be1d544
  • 检查 Master 节点数
# 配置 kubectl
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

$ kubectl get nodes
NAME           STATUS     ROLES    AGE     VERSION
k8s-master-1   NotReady   master   35m     v1.18.14
k8s-master-2   NotReady   master   8m14s   v1.18.14
k8s-master-3   NotReady   master   2m30s   v1.18.14

6、添加 Node 工作负载节点

部署完高可用的 Master 控制平面之后,我们就可以注册任意个 Node 工作负载节点了。

  • 添加 Node
kubeadm join 192.168.0.100:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:88dc9773b5dfc0cde6082314a1a4a9bbdb6ddfd3f1f84a7113581a3b07e839e1

W1221 00:39:36.256784   29495 join.go:346] [preflight] WARNING: JoinControlPane.controlPlane settings will be ignored when control-plane flag is not set.
[preflight] Running pre-flight checks
[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'
[kubelet-start] Downloading configuration for the kubelet from the "kubelet-config-1.18" 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] Starting the kubelet
[kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap...

This node has joined the cluster:
* Certificate signing request was sent to apiserver and a response was received.
* The Kubelet was informed of the new secure connection details.

Run 'kubectl get nodes' on the control-plane to see this node join the cluster.
  • 检查 Node:
$ kubectl get nodes
NAME           STATUS     ROLES    AGE     VERSION
k8s-master-1   NotReady   master   37m     v1.18.14
k8s-master-2   NotReady   master   10m     v1.18.14
k8s-master-3   NotReady   master   4m24s   v1.18.14
k8s-node-1     NotReady   <none>   51s     v1.18.14
k8s-node-2     NotReady   <none>   48s     v1.18.14

7、安装 CNI 网络插件

我们选择使用 Calico SDN 方案。官方文档:https://docs.projectcalico.org/about/about-calico

注意

  1. Pod 网络不得与任何主机网络重叠:所以我们在执行 kubeadm init 时显式指定了 --pod-network-cidr 参数。
  2. 确保 CNI 网络插件支持 RBAC(基于角色的访问控制)
  3. 确保 CNI 支持 IPv6 或 IPv4v6,当你需要使用的时候
  4. 在 OpenStack 环境中要关闭 “端口安全” 功能,否则 Calico IPIP 隧道无法打通
  • 安装
$ kubectl apply -f https://docs.projectcalico.org/manifests/calico.yaml

configmap/calico-config created
customresourcedefinition.apiextensions.k8s.io/bgpconfigurations.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/bgppeers.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/blockaffinities.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/clusterinformations.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/felixconfigurations.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/hostendpoints.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/ipamblocks.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/ipamconfigs.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/ipamhandles.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/ippools.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/kubecontrollersconfigurations.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/networkpolicies.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/networksets.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.apps/calico-node created
serviceaccount/calico-node created
deployment.apps/calico-kube-controllers created
serviceaccount/calico-kube-controllers created
poddisruptionbudget.policy/calico-kube-controllers created
  • 检查 Calico Pods
$ watch kubectl get pod --all-namespaces

Every 2.0s: kubectl get pod --all-namespaces                                                                                                                                        Mon Dec 21 13:12:30 2020

NAMESPACE     NAME                                       READY   STATUS    RESTARTS   AGE
kube-system   calico-kube-controllers-7dbc97f587-nqrxv   1/1     Running   0          9m34s
kube-system   calico-node-47xmr                          1/1     Running   0          9m34s
kube-system   calico-node-8zwbg                          1/1     Running   0          9m34s
kube-system   calico-node-dj4qt                          1/1     Running   0          9m34s
kube-system   calico-node-glqqj                          1/1     Running   0          9m34s
kube-system   calico-node-jb4t4                          1/1     Running   0          9m34s
kube-system   coredns-7ff77c879f-fh9vb                   1/1     Running   0          13h
kube-system   coredns-7ff77c879f-qmk7z                   1/1     Running   0          13h
kube-system   etcd-k8s-master-1                          1/1     Running   0          13h
kube-system   etcd-k8s-master-2                          1/1     Running   0          12h
kube-system   etcd-k8s-master-3                          1/1     Running   0          12h
kube-system   kube-apiserver-k8s-master-1                1/1     Running   0          13h
kube-system   kube-apiserver-k8s-master-2                1/1     Running   0          12h
kube-system   kube-apiserver-k8s-master-3                1/1     Running   0          12h
kube-system   kube-controller-manager-k8s-master-1	 1/1     Running   1          13h
kube-system   kube-controller-manager-k8s-master-2	 1/1     Running   0          12h
kube-system   kube-controller-manager-k8s-master-3	 1/1     Running   0          12h
kube-system   kube-proxy-7hx55                           1/1     Running   0          13h
kube-system   kube-proxy-8dmc4                           1/1     Running   0          12h
kube-system   kube-proxy-9clqs                           1/1     Running   0          12h
kube-system   kube-proxy-cq5tq                           1/1     Running   0          12h
kube-system   kube-proxy-pm79q                           1/1     Running   0          12h
kube-system   kube-scheduler-k8s-master-1                1/1     Running   1          13h
kube-system   kube-scheduler-k8s-master-2                1/1     Running   0          12h
kube-system   kube-scheduler-k8s-master-3                1/1     Running   0          12h
  • 检查 Cluster 节点的状态:安装了 CNI 之后节点的状态应该是 Ready 的。
$ kubectl get nodes
NAME           STATUS   ROLES    AGE   VERSION
k8s-master-1   Ready    master   13h   v1.18.14
k8s-master-2   Ready    master   12h   v1.18.14
k8s-master-3   Ready    master   12h   v1.18.14
k8s-node-1     Ready    <none>   12h   v1.18.14
k8s-node-2     Ready    <none>   12h   v1.18.14

8、安装 Metrics Server

Kubernetes Metrics Server

Kubernetes Metrics Server 是 Cluster 的核心监控数据的聚合器,kubeadm 默认是不部署的。

Metrics Server 供 Dashboard 等其他组件使用,是一个扩展的 APIServer,依赖于 API Aggregator。所以,在安装 Metrics Server 之前需要先在 kube-apiserver 中开启 API Aggregator。

  • Metrics API 只可以查询当前的度量数据,并不保存历史数据
  • Metrics API URI 为 /apis/metrics.k8s.io/,在 k8s.io/metrics 下维护
  • 必须部署 metrics-server 才能使用该 API,metrics-server 通过调用 kubelet Summary API 获取数据

使用 Metrics Server 有必备两个条件:

  1. API Server 启用 Aggregator Routing 支持。否则 API Server 不识别请求:
Error from server (ServiceUnavailable): the server is currently unable to handle the request (get pods.metrics.k8s.io)
  1. API Server 能访问 Metrics Server Pod IP。否则 API Server 无法访问 Metrics Server:
E1223 07:23:04.330206       1 available_controller.go:420] v1beta1.metrics.k8s.io failed with: failing or missing response from https://10.171.248.214:4443/apis/metrics.k8s.io/v1beta1: Get https://10.171.248.214:4443/apis/metrics.k8s.io/v1beta1: net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)

启用 API Aggregator

API Aggregation 允许在不修改 Kubernetes 核心代码的同时扩展 Kubernetes API,即:将第三方服务注册到 Kubernetes API 中,这样就可以通过 Kubernetes API 来访问第三方服务了,例如:Metrics Server API。

注:另外一种扩展 Kubernetes API 的方法是使用 CRD(Custom Resource Definition,自定义资源定义)。

  • 检查 API Server 是否开启了 Aggregator Routing:查看 API Server 是否具有 --enable-aggregator-routing=true 选项。
$ ps -ef | grep apiserver
root     23896 29500  0 12:40 pts/0    00:00:00 grep --color=auto apiserver
root     28613 28551  1 12月21 ?      01:05:29 kube-apiserver --advertise-address=192.168.0.112 --allow-privileged=true --authorization-mode=Node,RBAC --client-ca-file=/etc/kubernetes/pki/ca.crt --enable-admission-plugins=NodeRestriction --enable-bootstrap-token-auth=true --etcd-cafile=/etc/kubernetes/pki/etcd/ca.crt --etcd-certfile=/etc/kubernetes/pki/apiserver-etcd-client.crt --etcd-keyfile=/etc/kubernetes/pki/apiserver-etcd-client.key --etcd-servers=https://127.0.0.1:2379 --insecure-port=0 --kubelet-client-certificate=/etc/kubernetes/pki/apiserver-kubelet-client.crt --kubelet-client-key=/etc/kubernetes/pki/apiserver-kubelet-client.key --kubelet-preferred-address-types=InternalIP,ExternalIP,Hostname --proxy-client-cert-file=/etc/kubernetes/pki/front-proxy-client.crt --proxy-client-key-file=/etc/kubernetes/pki/front-proxy-client.key --requestheader-allowed-names=front-proxy-client --requestheader-client-ca-file=/etc/kubernetes/pki/front-proxy-ca.crt --requestheader-extra-headers-prefix=X-Remote-Extra- --requestheader-group-headers=X-Remote-Group --requestheader-username-headers=X-Remote-User --secure-port=6443 --service-account-key-file=/etc/kubernetes/pki/sa.pub --service-cluster-ip-range=172.16.0.0/16 --tls-cert-file=/etc/kubernetes/pki/apiserver.crt --tls-private-key-file=/etc/kubernetes/pki/apiserver.key
  • 修改每个 API Server 的 kube-apiserver.yaml 配置开启 Aggregator Routing:修改 manifests 配置后会 API Server 会自动重启生效。
$ vi /etc/kubernetes/manifests/kube-apiserver.yaml
...
spec:
  containers:
  - command:
...
  - --enable-aggregator-routing=true

安装 Metrics Server

  • 检查 Cluster 是否安装了 Metrics Server
$ kubectl top pods
Error from server (NotFound): the server could not find the requested resource (get services http:heapster:)
  • 部署 Metrics Server
# 下载 YAML 文件
wget https://github.com/kubernetes-sigs/metrics-server/releases/download/v0.4.1/components.yaml

# 编辑修改 metrics-server 的启动参数:
#  --kubelet-insecure-tls 跳过 TLS 认证,否则会出现 x509 的认证问题,用于测试环境。
#  --kubelet-preferred-address-types=InternalIP 使用 Node IP 进行通信。
      - args:
        - --cert-dir=/tmp
        - --secure-port=4443
        - --kubelet-preferred-address-types=InternalIP
        - --kubelet-use-node-status-port
        - --kubelet-insecure-tls

# 部署
$ kubectl apply -f components.yaml
serviceaccount/metrics-server created
clusterrole.rbac.authorization.k8s.io/system:aggregated-metrics-reader created
clusterrole.rbac.authorization.k8s.io/system:metrics-server created
rolebinding.rbac.authorization.k8s.io/metrics-server-auth-reader created
clusterrolebinding.rbac.authorization.k8s.io/metrics-server:system:auth-delegator created
clusterrolebinding.rbac.authorization.k8s.io/system:metrics-server created
service/metrics-server created
deployment.apps/metrics-server created
apiservice.apiregistration.k8s.io/v1beta1.metrics.k8s.io created

注意:如果出现了 ErrImagePull 的问题,那么意味着 k8s.gcr.io/metrics-server/metrics-server:v0.4.1 镜像下载失败了:

$ docker pull k8s.gcr.io/metrics-server/metrics-server:v0.4.1
Error response from daemon: Get https://k8s.gcr.io/v2/: net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)

这时候就需要我们在每个节点上都手动的下载镜像了:

$ docker pull bitnami/metrics-server:0.4.1

$ docker tag bitnami/metrics-server:0.4.1 k8s.gcr.io/metrics-server/metrics-server:v0.4.1

$ docker images
REPOSITORY                                                        TAG                 IMAGE ID            CREATED             SIZE
bitnami/metrics-server                                            0.4.1               4fb6df85a88d        6 hours ago         171MB
k8s.gcr.io/metrics-server/metrics-server                          v0.4.1              4fb6df85a88d        6 hours ago         171MB

然后再次执行 Metrics Server 的部署指令。

  • 检查 Metrics Server Service
$ kubectl get svc --all-namespaces | grep metrics-server
kube-system   metrics-server   ClusterIP   172.16.128.176   <none>        443/TCP                  5h55m
  • 检查 API Server 是否可以连通 Metrics Server
$ kubectl describe svc metrics-server -n kube-system
Name:              metrics-server
Namespace:         kube-system
Labels:            k8s-app=metrics-server
Annotations:       Selector:  k8s-app=metrics-server
Type:              ClusterIP
IP:                172.16.128.176
Port:              https  443/TCP
TargetPort:        https/TCP
Endpoints:         10.171.248.214:4443
Session Affinity:  None
Events:            <none>

# 在 Master Node 上 Ping。
$ ping 10.171.248.214
64 bytes from 10.171.248.214: icmp_seq=1 ttl=63 time=0.282 ms
  • 检查 Metrics Server
$ kubectl top nodes
NAME           CPU(cores)   CPU%   MEMORY(bytes)   MEMORY%
k8s-master-1   174m         8%     1156Mi          66%
k8s-master-2   123m         6%     1134Mi          65%
k8s-master-3   104m         5%     1075Mi          61%
k8s-node-1     78m          3%     853Mi           49%
k8s-node-2     78m          3%     824Mi           47%

9、安装 Dashboard GUI

默认情况下不会部署 Dashboard,需要我们手动安装。在安装 Dashboard 之前我们还需要确保安装了 Metrics Server。否则,错误提示我们在 Cluster 中没有安装 Metrics Server。

$ kubectl logs -f -n kubernetes-dashboard dashboard-metrics-scraper-6b4884c9d5-qppkd
192.168.0.208 - - [21/Dec/2020:07:54:08 +0000] "GET / HTTP/1.1" 200 6 "" "kube-probe/1.18"
{"level":"error","msg":"Error scraping node metrics: the server is currently unable to handle the request (get nodes.metrics.k8s.io)","time":"2020-12-21T07:54:09Z"}

$ kubectl logs -f -n kubernetes-dashboard kubernetes-dashboard-7b544877d5-p6g8t
2020/12/21 07:54:48 Metric client health check failed: the server is currently unable to handle the request (get services dashboard-metrics-scraper). Retrying in 30 seconds.

另外,官方 YAML 部署的 Dashboard 的 Service 也不是 NodePort 类型的,我们需要手动修改。

  • 编辑
$ wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0/aio/deploy/recommended.yaml

$ vi recommended.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: 30000
  selector:
    k8s-app: kubernetes-dashboard

---
  • 部署:出于安全访问的考虑,默认情况下,Dashboard 会使用最基础的 RBAC 配置进行部署。
$ kubectl create -f recommended.yaml
namespace/kubernetes-dashboard created
serviceaccount/kubernetes-dashboard created
service/kubernetes-dashboard created
secret/kubernetes-dashboard-certs created
secret/kubernetes-dashboard-csrf created
secret/kubernetes-dashboard-key-holder created
configmap/kubernetes-dashboard-settings created
role.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrole.rbac.authorization.k8s.io/kubernetes-dashboard created
rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
deployment.apps/kubernetes-dashboard created
service/dashboard-metrics-scraper created
deployment.apps/dashboard-metrics-scraper created
  • 检查 Dashboard Pods
$ kubectl get pods --all-namespaces | grep dashboard
kubernetes-dashboard   dashboard-metrics-scraper-6b4884c9d5-ctn6h   1/1     Running   0          79s
kubernetes-dashboard   kubernetes-dashboard-7b544877d5-sghsf        1/1     Running   0          79s
  • 检查 Dashboard Services:检查是否与 YAML 描述的一致。
$ kubectl get svc -n kubernetes-dashboard
NAME                        TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)         AGE
dashboard-metrics-scraper   ClusterIP   172.16.165.243   <none>        8000/TCP        2m32s
kubernetes-dashboard        NodePort    172.16.219.86    <none>        443:30000/TCP   2m33s

10、访问 Dashboard UI

因为 kubernetes-dashboard Service 是 NodePod 类型,所以我们使用任意节点 IP + NodePortNum 就可以访问了。

注意:NodePort 并非 VIP HA LB 的方式,所以我们可以使用高可用部署环境中的 Load Balancer 进行代理。

由于 Dashboard 默认是自建的 HTTPS 证书,该证书是不受浏览器信任的,强制跳转即可。

kubespray 部署高可用集群 kubeadm高可用_网络_08

登录 Dashboard 的时候支持 Kubeconfig 和 Token 两种认证方式,由于 Kubeconfig 中也依赖 Token 字段,所以生成 Token 这个步骤是必不可少的。

  • 创建 Dashboard Admin 管理员
$ cat dashboard-admin.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: dashboard-admin
  namespace: kubernetes-dashboard

$ kubectl create -f ./dashboard-admin.yaml
serviceaccount/dashboard-admin created

# CLI: kubectl create serviceaccount dashboard-admin -n kubernetes-dashboard
  • 为 Dashboard Admin 分配权限
$ cat dashboard-admin-bind-cluster-role.yaml

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: dashboard-admin-bind-cluster-role
  labels:
    k8s-app: kubernetes-dashboard
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: dashboard-admin
  namespace: kubernetes-dashboard

$ kubectl create -f ./dashboard-admin-bind-cluster-role.yaml
clusterrolebinding.rbac.authorization.k8s.io/dashboard-admin-bind-cluster-role created

# CLI: kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kubernetes-dashboard:dashboard-admin
  • 生成 Token
$ kubectl -n kubernetes-dashboard describe secret $(kubectl -n kubernetes-dashboard get secret | grep dashboard-admin | awk '{print $1}')
Name:         dashboard-admin-token-bc2dh
Namespace:    kubernetes-dashboard
Labels:       <none>
Annotations:  kubernetes.io/service-account.name: dashboard-admin
              kubernetes.io/service-account.uid: 3c26e908-49b2-4de8-8f08-699dba736a56

Type:  kubernetes.io/service-account-token

Data
====
ca.crt:     1025 bytes
namespace:  20 bytes
token:      eyJhbGciOiJSUzI1NiIsImtpZCI6IkV3a2JIWGhCdTFTSEFpd2hxam1WM29RTzQwcXdlT2dLYlRTRFU2TGotNHMifQ.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.v24ad9kFp4_kEUo4pPVRxqHxe6rXCv4kZryR3QoWrCKTdHM2FmJPrU1q_w5wGyXVShQQGyBlQJpdAAX5RAIy4gVvLLbc7W9qE74jHVijb4pBp9j8r-lsYpGvpiXadVCqXYCXHBxQSeYKXNM6hwDGKFGxQZ2LDA8K_j590fVeozSxM1RBJxetM4KfF0KomDurOhjITu0rortufeKhkOvRcoB0EikPkwqbU0Q5Ip7m_YIYHZsEqo292GieTyfZIM0KRLGGn4GX53qTbgk1bhQYsequUjs3sKw5Ng8vSOq8NPX0vB88Mjl0fzPWtKvnvpWokg1JL_fW4-qKA7HbUcenXQ
  • 访问

11、通过 NFS 实现持久化存储

NFS Server 安装

$ yum install -y nfs-utils
$ yum install -y rpcbind

$ mkdir /public
$ vi /etc/exports
	/public 192.168.186.*

$ systemctl start rpcbind && systemctl enable rpcbind && systemctl status rpcbind
$ systemctl start nfs-server && systemctl enable nfs-server && systemctl status nfs-server

NFS Client 挂载

$ mkdir /mnt/public

$ vi /etc/fstab
	192.168.186.198:/public /mnt/public nfs defaults 0 0

$ mount -a

Kubernetes 部署 nfs-client-provisioner

  • 下载 nfs-client
git clone https://github.com/kubernetes-sigs/nfs-subdir-external-provisioner.git
  • 创建 ServiceAccount
$ NS=$(kubectl config get-contexts|grep -e "^\*" |awk '{print $5}')
$ NAMESPACE=${NS:-default}
$ cd nfs-subdir-external-provisioner/deploy
$ sed -i'' "s/namespace:.*/namespace: $NAMESPACE/g" ./deploy/rbac.yaml ./deployment.yaml
$ kubectl create -f ./rbac.yaml
  • 部署 NFS Provisioner
$ vi deployment.yaml
...
    spec:
      serviceAccountName: nfs-client-provisioner
      containers:
        - name: nfs-client-provisioner
          image: quay.io/external_storage/nfs-client-provisioner:latest
          volumeMounts:
            - name: nfs-client-root
              mountPath: /persistentvolumes
          env:
            - name: PROVISIONER_NAME
              value: fuseim.pri/ifs
            - name: NFS_SERVER
              value: 192.168.186.198  # NFS Server IP
            - name: NFS_PATH
              value: /public          # Share Dir Path
      volumes:
        - name: nfs-client-root
          nfs:
            server: 192.168.186.198   # NFS Server IP
            path: /public             # Share Dir Path
            
 
# 创建 NFS Provisioner
$ kubectl apply -f deployment.yaml
  • 创建 NFS Storage Class
kubectl apply -f class.yaml