本文最后更新于 2020 年 4 月 26 日,文章已超过 6 个月!内容可能已失效,请自行测试 ~

基础环境配置

确保每个节点上 MAC 地址和 product_uuid 的唯一性

  • 您可以使用命令 ip link 或 ifconfig -a 来获取网络接口的 MAC 地址
  • 可以使用 sudo cat /sys/class/dmi/id/product_uuid 命令对 product_uuid 校验

一般来讲,硬件设备会拥有唯一的地址,但是有些虚拟机的地址可能会重复。Kubernetes 使用这些值来唯一确定集群中的节点。 如果这些值在每个节点上不唯一,可能会导致安装失败

编辑hosts

master和worker都需要编辑

[root@master-all ~]# cat /etc/hosts
192.168.230.202 master-all
192.168.230.203 Node-1

关闭Swap(交换分区)

master和worker都需要执行

临时关闭

[root@master-all ~]# swapoff -a

永久关闭,需重启

[root@master-all ~]# sed -i 's/\(.*[[:space:]]swap[[:space:]].*\)/#\1/g' /etc/fstab

关闭selinux

master和worker都需要执行

临时关闭

[root@master-all ~]# setenforce 0

永久关闭,需重启

[root@master-all ~]# sed -i 's/\(^SELINUX=\).*/\1disabled/' /etc/selinux/config

关闭防火墙

master和worker都需要执行

[root@master-all ~]# systemctl stop firewalld && systemctl disable firewalld

修改系统参数

master和worker都需要编辑

[root@master-all ~]# vim /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
[root@master-all ~]# modprobe br_netfilter
[root@master-all ~]# sysctl -p /etc/sysctl.d/k8s.conf

安装Docker

master和worker都需要安装

[root@master-all ~]# yum -y install docker 
[root@master-all ~]# systemctl enable docker && systemctl start docker
Created symlink from /etc/systemd/system/multi-user.target.wants/docker.service to /usr/lib/systemd/system/docker.service.

此处使用阿里云镜像站

[root@Node-1 ~]# vim /etc/docker/daemon.json
{
  "registry-mirrors": ["https://n275i9sm.mirror.aliyuncs.com"]
}
[root@master-all ~]# systemctl daemon-reload
[root@master-all ~]# systemctl restart docker

安装k8s组件

配置国内源repo文件/etc/yum.repos.d/kubernetes.repo

[root@master-all ~]# vim /etc/yum.repos.d/kubernetes.repo 
[kubernetes]
name=Kubernetes
baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
exclude=kube*

安装Kubernetes组件

–disableexcludes=kubernetes

只从指定repo中获取
[root@master-all ~]# yum -y install kubelet kubeadm kubectl --disableexcludes=kubernetes
[root@master-all ~]# systemctl enable kubelet && systemctl start kubelet

Master安装

获取初始化文件

[root@master-all ~]# kubeadm config print init-defaults > kubeadm-init.yaml
[root@master-all ~]# vim kubeadm-init.yaml 

将advertiseAddress: 1.2.3.4修改为本机IP地址
将imageRepository: k8s.gcr.io修改为imageRepository: registry.cn-hangzhou.aliyuncs.com/google_containers
apiVersion: kubeadm.k8s.io/v1beta2
bootstrapTokens:
- groups:
  - system:bootstrappers:kubeadm:default-node-token
  token: abcdef.0123456789abcdef
  ttl: 24h0m0s
  usages:
  - signing
  - authentication
kind: InitConfiguration
localAPIEndpoint:
  advertiseAddress: 192.168.230.202
  bindPort: 6443
nodeRegistration:
  criSocket: /var/run/dockershim.sock
  name: master-all
  taints:
  - effect: NoSchedule
    key: node-role.kubernetes.io/master
---
apiServer:
  timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta2
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controllerManager: {}
dns:
  type: CoreDNS
etcd:
  local:
    dataDir: /var/lib/etcd
imageRepository: registry.cn-hangzhou.aliyuncs.com/google_containers
kind: ClusterConfiguration
kubernetesVersion: v1.18.0
networking:
  dnsDomain: cluster.local
  serviceSubnet: 10.96.0.0/12
scheduler: {}

拉取images镜像

[root@master-all ~]# kubeadm config images pull --config kubeadm-init.yaml 
W0411 17:59:25.394894    1717 configset.go:202] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver:v1.18.0
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager:v1.18.0
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler:v1.18.0
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy:v1.18.0
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.2
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/etcd:3.4.3-0
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:1.6.7

初始化

[root@master-all ~]# kubeadm init --config kubeadm-init.yaml 
W0411 18:00:39.037355    2000 configset.go:202] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]
[init] Using Kubernetes version: v1.18.0
[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 [master-all kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.230.202]
[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 [master-all localhost] and IPs [192.168.230.202 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [master-all localhost] and IPs [192.168.230.202 127.0.0.1 ::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"
W0411 18:00:41.149242    2000 manifests.go:225] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[control-plane] Creating static Pod manifest for "kube-scheduler"
W0411 18:00:41.149789    2000 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 15.004506 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] Skipping phase. Please see --upload-certs
[mark-control-plane] Marking the node master-all as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node master-all 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/

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

kubeadm join 192.168.230.202:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:d3cfcef4ced07d6f648074a15026599db6671a780f9032ec425c3fa75fce8bda 

如需清除缓存可执行:

kubeadm reset

拷贝授权文件

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

网络配置

下载calico配置

需要注意的是, calico.yaml中的IP和kubeadm-init.yaml需要保持一致, 要么初始化前修改kubeadm-init.yaml, 要么初始化后修改calico.yaml.
[root@master-all ~]# wget https://docs.projectcalico.org/v3.11/manifests/calico.yaml
[root@master-all ~]# vim calico.yaml
              value: "10.96.0.0/12"

开始安装

[root@master-all ~]# 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
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

等待几分钟后查看Node网络状态

[root@master-all ~]# kubectl get nodes
NAME         STATUS   ROLES    AGE   VERSION
master-all   Ready    master   12m   v1.18.1
[root@master-all ~]# kubectl get pod -o wide --all-namespaces
NAMESPACE     NAME                                       READY   STATUS    RESTARTS   AGE   IP                NODE         NOMINATED NODE   READINESS GATES
kube-system   calico-kube-controllers-75d56dfc47-6hxnj   1/1     Running   0          10m   10.109.177.70     master-all   <none>           <none>
kube-system   calico-node-tpz8m                          1/1     Running   1          10m   192.168.230.202   master-all   <none>           <none>
kube-system   coredns-546565776c-4pdj9                   1/1     Running   2          12m   10.109.177.71     master-all   <none>           <none>
kube-system   coredns-546565776c-6bcw8                   1/1     Running   2          12m   10.109.177.72     master-all   <none>           <none>
kube-system   etcd-master-all                            1/1     Running   2          12m   192.168.230.202   master-all   <none>           <none>
kube-system   kube-apiserver-master-all                  1/1     Running   2          12m   192.168.230.202   master-all   <none>           <none>
kube-system   kube-controller-manager-master-all         1/1     Running   1          12m   192.168.230.202   master-all   <none>           <none>
kube-system   kube-proxy-ln9kx                           1/1     Running   2          12m   192.168.230.202   master-all   <none>           <none>
kube-system   kube-scheduler-master-all                  1/1     Running   2          12m   192.168.230.202   master-all   <none>           <none>

Node Worker节点

node节点环境安装请参照 基础环境配置

添加node节点至master

[root@Node-1 ~]# kubeadm join 192.168.230.202:6443 --token abcdef.0123456789abcdef     --discovery-token-ca-cert-hash sha256:d3cfcef4ced07d6f648074a15026599db6671a780f9032ec425c3fa75fce8bda 
W0411 18:15:25.273383    1583 join.go:346] [preflight] WARNING: JoinControlPane.controlPlane settings will be ignored when control-plane flag is not set.
[preflight] Running pre-flight checks
	[WARNING Service-Kubelet]: kubelet service is not enabled, please run 'systemctl enable kubelet.service'
[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.

拷贝授权文件

[root@Node-1 ~]# mkdir -p $HOME/.kube
[root@Node-1 ~]# cp -i /etc/kubernetes/kubelet.conf $HOME/.kube/config

验证

[root@Node-1 ~]# kubectl get nodes
NAME         STATUS   ROLES    AGE    VERSION
master-all   Ready    master   16m    v1.18.1
node-1       Ready    <none>   113s   v1.18.1

遇到的问题

报错:

failed to run Kubelet: failed to create kubelet: misconfiguration: kubelet cgroup driver: "cgroupfs" is different from docker cgroup driver: "systemd"

解决方法

[root@master-all ~]# sed -i 's/\(.*native.cgroupdriver=\)systemd\(.*\)/\1cgroupfs\2/' /lib/systemd/system/docker.service
[root@master-all ~]# systemctl daemon-reload
[root@master-all ~]# systemctl restart docker

报错:

[root@master-all ~]# kubectl get pod
The connection to the server localhost:8080 was refused - did you specify the right host or port?

解决方法:

[root@master-all ~]# mkdir -p $HOME/.kube
[root@master-all ~]# cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
#如果非root用户需chown授权

报错:

[root@Node-1 ~]# kubeadm join 192.168.230.101:6443 --token n3qdmn.btk974cnv1bfskbt \
>     --discovery-token-ca-cert-hash sha256:859476404c5ed23aef3d78e3b8fc09684dde7fbf8ce0ad446774162ccec2e0d1 
W0319 09:28:32.847414   24070 join.go:346] [preflight] WARNING: JoinControlPane.controlPlane settings will be ignored when control-plane flag is not set.
[preflight] Running pre-flight checks
	[WARNING Service-Kubelet]: kubelet service is not enabled, please run 'systemctl enable kubelet.service'
error execution phase preflight: [preflight] Some fatal errors occurred:
	[ERROR FileContent--proc-sys-net-bridge-bridge-nf-call-iptables]: /proc/sys/net/bridge/bridge-nf-call-iptables contents are not set to 1
	[ERROR FileContent--proc-sys-net-ipv4-ip_forward]: /proc/sys/net/ipv4/ip_forward contents are not set to 1
[preflight] If you know what you are doing, you can make a check non-fatal with `--ignore-preflight-errors=...`
To see the stack trace of this error execute with --v=5 or higher

解决方法:

[root@Node-1 ~]# vim /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
[root@Node-1 ~]# sysctl -p /etc/sysctl.d/k8s.conf

该文章采用「CC 协议」,转载必须注明作者和本文链接.