安装
在大致了解了一些k8s的基本概念之后,我们实际部署一个k8s集群,做进一步的了解
1. 裸机安装
采用三台机器,一台机器为Master(控制面板组件)两台机器为Node(工作节点)
机器的准备有两种方式:
- VMware虚拟机 centos7操作系统 三台
- 云厂商 租用服务器 按量付费 费用极低 用完销毁即可
1.1 设置主机名
# 每个节点分别设置对应主机名
hostnamectl set-hostname master
hostnamectl set-hostname node1
hostnamectl set-hostname node2
1.2 修改hosts
# 所有节点都修改 hosts
vim /etc/hosts
192.168.200.104 master
192.168.200.105 node1
192.168.200.106 node2
192.168.66.128 master
192.168.66.131 node1
192.168.66.132 node2
1.3 关闭防火墙
# 所有节点关闭 SELinux
setenforce 0
sed -i --follow-symlinks 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/sysconfig/selinux
所有节点确保防火墙关闭
systemctl stop firewalld
systemctl disable firewalld
关闭swap分区:
# 临时关闭
swapoff -a
# 永久关闭
vim /etc/fstab
#注释下面这行,或使用 sed 命令注释 sed -ri 's/.*swap.*/#&/' /etc/fstab
#/dev/mapper/centos-swap swap swap defaults 0 0
# 查看是否关闭成功
free -m
# 若都显示 0 则表示关闭成功,需要重启服务器生效,可以使用 reboot 或 shutdown -r now 命令重启
[root@master ~]# free -m
total used free shared buff/cache available
Mem: 3770 305 3115 11 350 3242
Swap: 0 0 0
同步网络时间:
# 如果没有 ntpdate ,使用如下命令安装
# yum install -y ntpdate
ntpdate ntp1.aliyun.com # 使用
date
1.4 添加安装源
#所有节点
# 添加 k8s 安装源
cat <<EOF > 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
mv kubernetes.repo /etc/yum.repos.d/
# 添加 Docker 安装源
yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
如果报错 -bash: yum-config-manager: command not found 则运行 yum install -y yum-utils
如果安装 yum-utils 报错 failure: repodata/repomd.xml from kubernetes: [Errno 256] No more mirrors to try.,则设置 repo_gpgcheck=0
1.5 安装所需组件
- Kubectl: Kubectl 管理 Kubernetes 集群命令行工具
- kubeadm:Kubeadm 是一个快捷搭建kubernetes(k8s)的安装工具,它提供了kubeadm init 以及kubeadm join这两个命令来快速创建kubernetes集群
- kubelet:kubelet 是在每个 Node 节点上运行的主要 “节点代理”。
# 所有节点
yum install -y kubelet-1.23.9 kubectl-1.23.9 kubeadm-1.23.9 docker-ce
1.6 启动
#所有节点
systemctl enable docker
systemctl start docker
systemctl enable kubelet
systemctl start kubelet
1.8 修改docker配置
# kubernetes 官方推荐 docker 等使用 systemd 作为 cgroupdriver,否则 kubelet 启动不了
cat <<EOF > daemon.json
{
"exec-opts": ["native.cgroupdriver=systemd"],
"registry-mirrors": ["https://tfm2bi1b.mirror.aliyuncs.com"]
}
EOF
mv daemon.json /etc/docker/
# 重启生效
systemctl daemon-reload
systemctl restart docker
1.9 kubeadm 初始化集群
#仅在主节点运行
# 失败了可以用 kubeadm reset 重置
#关闭交互分区
swapoff -a
#初始化集群控制台 Control plane
# apiserver-advertise-address: master 节点 IP
# image-repository:镜像仓库地址
# kubernetes-version: 版本号
# pod-network-cidr 和 service-cidr 不清楚如何设置,使用该默认值
# 查看其他默认值可使用命令: kubeadm config print init-defaults > kubeadm.yaml 查看默认初始化文件
kubeadm init \
--apiserver-advertise-address=192.168.66.133 \
--image-repository registry.aliyuncs.com/google_containers \
--kubernetes-version=v1.23.9 \
--pod-network-cidr=10.244.0.0/16 \
--service-cidr=10.96.0.0/16
# 记得把 kubeadm join xxx 保存起来
# 忘记了重新获取:kubeadm token create --print-join-command
# 复制授权文件,以便 kubectl 可以有权限访问集群
# 如果你其他节点需要访问集群,需要从主节点复制这个文件过去其他节点
mkdir -p $HOME/.kube
cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
chown $(id -u):$(id -g) $HOME/.kube/config
# 在其他机器上创建 ~/.kube/config 文件也能通过 kubectl 访问到集群
kubeadm join 192.168.200.101:6443 --token wou8ux.tpfiunjbgrjqy8vz --discovery-token-ca-cert-hash sha256:f1ae65b2e88427a44cd0883df9739bb13e3bb122227b7a12c4717d68c317cdc8
如果token过期,可以在master 主节点执行 kubeadm token create --print-join-command --ttl=0
,token 永不过期,获取到新的join命令
1.10 把工作节点加入集群
swapoff -a
kubeadm join 192.168.200.101:6443 --token wou8ux.tpfiunjbgrjqy8vz --discovery-token-ca-cert-hash sha256:f1ae65b2e88427a44cd0883df9739bb13e3bb122227b7a12c4717d68c317cdc8
1.11 安装网络插件
kube-flannel.yml
---
kind: Namespace
apiVersion: v1
metadata:
name: kube-flannel
labels:
pod-security.kubernetes.io/enforce: privileged
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: flannel
rules:
- apiGroups:
- ""
resources:
- pods
verbs:
- get
- apiGroups:
- ""
resources:
- nodes
verbs:
- list
- watch
- apiGroups:
- ""
resources:
- nodes/status
verbs:
- patch
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: flannel
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: flannel
subjects:
- kind: ServiceAccount
name: flannel
namespace: kube-flannel
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: flannel
namespace: kube-flannel
---
kind: ConfigMap
apiVersion: v1
metadata:
name: kube-flannel-cfg
namespace: kube-flannel
labels:
tier: node
app: flannel
data:
cni-conf.json: |
{
"name": "cbr0",
"cniVersion": "0.3.1",
"plugins": [
{
"type": "flannel",
"delegate": {
"hairpinMode": true,
"isDefaultGateway": true
}
},
{
"type": "portmap",
"capabilities": {
"portMappings": true
}
}
]
}
net-conf.json: |
{
"Network": "10.244.0.0/16",
"Backend": {
"Type": "vxlan"
}
}
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: kube-flannel-ds
namespace: kube-flannel
labels:
tier: node
app: flannel
spec:
selector:
matchLabels:
app: flannel
template:
metadata:
labels:
tier: node
app: flannel
spec:
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: kubernetes.io/os
operator: In
values:
- linux
hostNetwork: true
priorityClassName: system-node-critical
tolerations:
- operator: Exists
effect: NoSchedule
serviceAccountName: flannel
initContainers:
- name: install-cni-plugin
#image: flannelcni/flannel-cni-plugin:v1.1.0 for ppc64le and mips64le (dockerhub limitations may apply)
image: docker.io/rancher/mirrored-flannelcni-flannel-cni-plugin:v1.1.0
command:
- cp
args:
- -f
- /flannel
- /opt/cni/bin/flannel
volumeMounts:
- name: cni-plugin
mountPath: /opt/cni/bin
- name: install-cni
#image: flannelcni/flannel:v0.19.0 for ppc64le and mips64le (dockerhub limitations may apply)
image: docker.io/rancher/mirrored-flannelcni-flannel:v0.19.0
command:
- cp
args:
- -f
- /etc/kube-flannel/cni-conf.json
- /etc/cni/net.d/10-flannel.conflist
volumeMounts:
- name: cni
mountPath: /etc/cni/net.d
- name: flannel-cfg
mountPath: /etc/kube-flannel/
containers:
- name: kube-flannel
#image: flannelcni/flannel:v0.19.0 for ppc64le and mips64le (dockerhub limitations may apply)
image: docker.io/rancher/mirrored-flannelcni-flannel:v0.19.0
command:
- /opt/bin/flanneld
args:
- --ip-masq
- --kube-subnet-mgr
resources:
requests:
cpu: "100m"
memory: "50Mi"
limits:
cpu: "100m"
memory: "50Mi"
securityContext:
privileged: false
capabilities:
add: ["NET_ADMIN", "NET_RAW"]
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
- name: EVENT_QUEUE_DEPTH
value: "5000"
volumeMounts:
- name: run
mountPath: /run/flannel
- name: flannel-cfg
mountPath: /etc/kube-flannel/
- name: xtables-lock
mountPath: /run/xtables.lock
volumes:
- name: run
hostPath:
path: /run/flannel
- name: cni-plugin
hostPath:
path: /opt/cni/bin
- name: cni
hostPath:
path: /etc/cni/net.d
- name: flannel-cfg
configMap:
name: kube-flannel-cfg
- name: xtables-lock
hostPath:
path: /run/xtables.lock
type: FileOrCreate
kubectl apply -f kube-flannel.yml
1.12 安装 dashboard
github地址:https://github.com/kubernetes/dashboard/,
我们的版本为v1.23 所以安装 2.5.1版本
资料中的kubernetes-dashboard.yaml
执行安装:
kubectl apply -f kubernetes-dashboard.yaml
资料中dashboard-adminuser.yaml
想要访问dashboard服务,就要有访问权限,创建kubernetes-dashboard管理员角色
kubectl apply -f dashboard-adminuser.yaml
kubectl describe secrets -n kubernetes-dashboard admin-user-token | grep token | awk 'NR==3{print $2}'
获取到token:
eyJhbGciOiJSUzI1NiIsImtpZCI6Ik5nUVQzNjhGS0R6MGlWLU82VnFraEdpRWtCajFnQ1hhVWdfc1Fmbjl3NlEifQ.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.G9zvUV2X_h5lHmk5YF7evjlA78x8EMEpbdVySOijXgIbToHt8XUw5H5YKOMRgEvQ-hVM__BaPAH5MhtcIQLFD7VSr6sXEU3tbBDaPGVEEA8fl4HZh-lLkcGb1OpGmgdmM3-V7W2iere79kD6JDkpq4NzuKDu_-OLyMl2eyBuKunPICeV0KG75rzfglopIqkZ5U6lYdiG9B8Kyk51RIHq6303E-6iGNoSYVfPoqNtxpX3Ws7qitAX5nDJ9X1DLjBSH7TKjeaBxgm7MOF2BJHvIIVSkTv03aXvJZ96yZdEzUlF7fvMEnF7sSsqYBM8k-W1hQG-6J1-6Mn2JkwCAFf8TA
查看服务端口:
kubectl get pods --all-namespaces
kubectl describe pod kubernetes-dashboard --namespace=kubernetes-dashboard
kubectl get svc -n kubernetes-dashboard
登录:
https://192.168.200.101:32000
看到ui界面
出问题可清空一个iptables
systemctl stop kubelet
systemctl stop docker
iptables --flush
systemctl start kubelet
systemctl start docker
[root@node1 ~]# kubeadm init
I0407 11:20:08.423214 12515 version.go:255] remote version is much newer: v1.29.3; falling back to: stable-1.23
[init] Using Kubernetes version: v1.23.17
[preflight] Running pre-flight checks
[WARNING SystemVerification]: this Docker version is not on the list of validated versions: 26.0.0. Latest validated version: 20.10
[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'
error execution phase preflight: [preflight] Some fatal errors occurred:
[ERROR ImagePull]: failed to pull image k8s.gcr.io/kube-apiserver:v1.23.17: output: Error response from daemon: Get "https://k8s.gcr.io/v2/": net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)
, error: exit status 1
[ERROR ImagePull]: failed to pull image k8s.gcr.io/kube-controller-manager:v1.23.17: output: Error response from daemon: Get "https://k8s.gcr.io/v2/": dial tcp 74.125.203.82:443: i/o timeout (Client.Timeout exceeded while awaiting headers)
, error: exit status 1
[ERROR ImagePull]: failed to pull image k8s.gcr.io/kube-scheduler:v1.23.17: output: Error response from daemon: Get "https://k8s.gcr.io/v2/": context deadline exceeded
, error: exit status 1
[ERROR ImagePull]: failed to pull image k8s.gcr.io/kube-proxy:v1.23.17: output: Error response from daemon: Get "https://k8s.gcr.io/v2/": dial tcp 74.125.203.82:443: i/o timeout
, error: exit status 1
[ERROR ImagePull]: failed to pull image k8s.gcr.io/pause:3.6: output: Error response from daemon: Get "https://k8s.gcr.io/v2/": context deadline exceeded
, error: exit status 1
[ERROR ImagePull]: failed to pull image k8s.gcr.io/etcd:3.5.1-0: output: Error response from daemon: Get "https://k8s.gcr.io/v2/": context deadline exceeded
, error: exit status 1
[ERROR ImagePull]: failed to pull image k8s.gcr.io/coredns/coredns:v1.8.6: output: Error response from daemon: Get "https://k8s.gcr.io/v2/": net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)
, error: exit status 1
deadline exceeded
, error: exit status 1
[ERROR ImagePull]: failed to pull image k8s.gcr.io/etcd:3.5.1-0: output: Error response from daemon: Get “https://k8s.gcr.io/v2/”: context deadline exceeded
, error: exit status 1
[ERROR ImagePull]: failed to pull image k8s.gcr.io/coredns/coredns:v1.8.6: output: Error response from daemon: Get “https://k8s.gcr.io/v2/”: net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)
, error: exit status 1