Kubernetes最新版v1.27.4安装和集群搭建保姆级教程

1. Kubernetes 1.27.4 发布

一：k8s1.27.x 的概述
太平洋时间 2023 年 4 月 11 日，Kubernetes 1.27 正式发布。此版本距离上版本发布时隔 4 个月，是 2023 年的第一个版本。
新版本中 release 团队跟踪了 60 个 enhancements，比之前版本都要多得多。其中 13 个功能升级为稳定版，29 个已有功能进行优化升级为 Beta，另有 18 个 Alpha 级别的功能，大多数为全新功能。

1.1：k8s 1.27.x 更新
镜像仓库切换 http://k8s.gcr.io 到 http://registry.gcr.io
KEP-1847：StatefulSet PVC 自动删除功能特性 Beta
KEP-3453：优化大型集群中 kube-proxy 的 iptables 模式性能
KEP-2831 和 KEP-647：APIServer 和 Kubelet 的 Tracing 功能 Beta
KEP-3077：上下文日志
KEP-1287：Pod 资源的纵向弹性伸缩
KEP-3386：Kubelet 事件驱动 PLEG 升级为 Beta
KEP-3476：Volume Group 快照 Alpha（API）
KEP-3838 和 KEP-3521：Pod 调度就绪态功能增强
KEP-3243：Deployment 滚动更新过程中的调度优化
KEP-2876：使用通用表达式语言（CEL）来验证 CRD
KEP-2258：节点日志查询
KEP-3659：kubectl apply –prune 重新设计

2. 环境准备

2.1 主机操作系统说明

序号	操作系统及版本	备注
1	CentOS7.9

2.2 主机硬件配置说明

CPU	内存	硬盘	角色	主机名
2C	2G	50GB	master	Master01
2C	24G	50GB	worker(node)	Node02
2C	2G	50GB	worker(node)	Node03

2.3 主机名配置

由于本次使用3台主机完成kubernetes集群部署，其中1台为master节点,名称为k8s-master;其中2台为worker节点，名称分别为：k8s-k8s-node1及k8s-node2

master节点
# hostnamectl set-hostname master01
worker01节点
# hostnamectl set-hostname node01
worker02节点
# hostnamectl set-hostname nodeo2

2.4 主机名与IP地址解析

所有集群主机均需要进行配置。

# cat >> /etc/hosts << EOF

192.168.1.10 master01
192.168.1.11 node01
192.168.1.12 node02
EOF

# cat /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6

192.168.1.10 master01
192.168.1.11 node01
192.168.1.12 node02

2.5 防火墙配置

所有主机均需要操作。

关闭现有防火墙firewalld
# systemctl disable firewalld
# systemctl stop firewalld
# firewall-cmd --state
not running

2.6 SELINUX配置

所有主机均需要操作。修改SELinux配置需要重启操作系统。

# setenforce 0
# sed -ri 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config

2.7 时间同步配置

所有主机均需要操作。最小化安装系统需要安装ntpdate软件。

# yum -y install ntpdate
# crontab -l
0 */1 * * * /usr/sbin/ntpdate time1.aliyun.com

2.8 升级操作系统内核

所有主机均需要操作。

导入elrepo gpg key
# rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
安装elrepo YUM源仓库
# yum -y install https://www.elrepo.org/elrepo-release-7.el7.elrepo.noarch.rpm
安装kernel-ml版本，ml为长期稳定版本，lt为长期维护版本
# yum --enablerepo="elrepo-kernel" -y install kernel-ml.x86_64
设置grub2默认引导为0
# grub2-set-default 0
重新生成grub2引导文件
# grub2-mkconfig -o /boot/grub2/grub.cfg
更新后，需要重启，使用升级的内核生效。
# reboot
重启后，需要验证内核是否为更新对应的版本
# uname -r

2.9 配置内核转发及网桥过滤

所有主机均需要操作。

添加网桥过滤及内核转发配置文件
# cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
vm.swappiness = 0
EOF
# cat /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
vm.swappiness = 0
加载br_netfilter模块
# modprobe br_netfilter
查看是否加载
# lsmod | grep br_netfilter
br_netfilter           22256  0
bridge                151336  1 br_netfilter
加载网桥过滤及内核转发配置文件
# sysctl -p /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
vm.swappiness = 0

2.10 安装ipset及ipvsadm

所有主机均需要操作。

安装ipset及ipvsadm
# yum -y install ipset ipvsadm
配置ipvsadm模块加载方式
添加需要加载的模块
# cat > /etc/sysconfig/modules/ipvs.modules <<EOF
#!/bin/bash
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack
EOF
授权、运行、检查是否加载
# chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules && lsmod | grep -e ip_vs -e nf_conntrack

2.11 关闭SWAP分区

修改完成后需要重启操作系统，如不重启，可临时关闭，命令为swapoff -a

永远关闭swap分区，需要重启操作系统
# swapoff -a
# sed -i 's/.*swap.*/#&/g' /etc/fstab
# cat /etc/fstab
......

# /dev/mapper/centos-swap swap                    swap    defaults        0 0

在上一行中行首添加#

3. Docker准备

3.1 Docker安装YUM源准备

使用阿里云开源软件镜像站。

# wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo

3.2 Docker安装

# yum -y install docker-ce

3.3 启动Docker服务

# systemctl enable --now docker

3.4 修改cgroup方式

/etc/docker/daemon.json 默认没有此文件，需要单独创建

在/etc/docker/daemon.json添加如下内容
# cat > /etc/docker/daemon.json << EOF
{
  "registry-mirrors": ["https://84bkfzte.mirror.aliyuncs.com"],
  "exec-opts": ["native.cgroupdriver=systemd"]
}
EOF
# cat /etc/docker/daemon.json
{
  "registry-mirrors": ["https://84bkfzte.mirror.aliyuncs.com"],
  "exec-opts": ["native.cgroupdriver=systemd"]
}
# systemctl daemon-reload
# systemctl restart docker
# docker info

3.5 cri-dockerd安装

所有主机均需要操作。

下载cri-dockerd安装包，注意这里可能需要用科学上网
# wget https://github.com/Mirantis/cri-dockerd/releases/download/v0.3.1/cri-dockerd-0.3.1-3.el7.x86_64.rpm
安装cri-dockerd
# rpm -ivh cri-dockerd-0.3.1-3.el7.x86_64.rpm
修改镜像地址为国内，否则kubelet拉取不了镜像导致启动失败
# vi /usr/lib/systemd/system/cri-docker.service

ExecStart=/usr/bin/cri-dockerd --container-runtime-endpoint fd:// --pod-infra-container-image=registry.aliyuncs.com/google_containers/pause:3.7
启动cri-dockerd
# systemctl daemon-reload 
# systemctl enable cri-docker && systemctl start cri-docker

4 Kubernetes 1.27.4 集群部署

4.1 集群软件及版本说明

	kubeadm	kubelet	kubectl
版本	1.27.4	1.27.4	1.27.4
安装位置	集群所有主机	集群所有主机	集群所有主机
作用	初始化集群、管理集群等	用于接收api-server指令，对pod生命周期进行管理	集群应用命令行管理工具

kubernetes_YUM_265">4.2 kubernetes YUM源准备

所有节点均可安装

# 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

4.3 集群软件安装

安装
# yum install -y kubelet-1.27.4 kubeadm-1.27.4 kubectl-1.27.4

4.4 配置kubelet

为了实现docker使用的cgroupdriver与kubelet使用的cgroup的一致性，建议修改如下文件内容。

# vim /etc/sysconfig/kubelet
KUBELET_EXTRA_ARGS="--cgroup-driver=systemd"
设置kubelet为开机自启动即可，由于没有生成配置文件，集群初始化后自动启动
# systemctl enable kubelet && systemctl restart kubelet

4.5 集群初始化

在master节点安装

注意apiserver-advertise-address地址修改成相应的IP，pod-network-cidr地址不要改变，因为安装Calico默认地址：
[root@k8s-master ~]# kubeadm init \
  --apiserver-advertise-address=192.168.1.10 \
  --image-repository registry.aliyuncs.com/google_containers \
  --kubernetes-version v1.27.4 \
  --service-cidr=10.96.0.0/12 \
  --pod-network-cidr=10.244.0.0/16 \
  --cri-socket=unix:///var/run/cri-dockerd.sock \
  --ignore-preflight-errors=all
初始化过程输出
[init] Using Kubernetes version: v1.27.0
[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'
W0415 17:50:39.742407    3689 images.go:80] could not find officially supported version of etcd for Kubernetes v1.27.0, falling back to the nearest etcd version (3.5.7-0)
[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 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.1.10]
[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 localhost] and IPs [192.168.1.10 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [k8s-master localhost] and IPs [192.168.1.10 127.0.0.1 ::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
[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
[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"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
W0415 17:51:04.317762    3689 images.go:80] could not find officially supported version of etcd for Kubernetes v1.27.0, falling back to the nearest etcd version (3.5.7-0)
[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 6.002359 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config" 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 k8s-master as control-plane by adding the labels: [node-role.kubernetes.io/control-plane node.kubernetes.io/exclude-from-external-load-balancers]
[mark-control-plane] Marking the node k8s-master as control-plane by adding the taints [node-role.kubernetes.io/control-plane:NoSchedule]
[bootstrap-token] Using token: 6t01k9.671ufvohi6l6fu7g
[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

Alternatively, if you are the root user, you can run:

  export KUBECONFIG=/etc/kubernetes/admin.conf

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 192.168.1.10:6443 --token 6t01k9.671ufvohi6l6fu7g \
        --discovery-token-ca-cert-hash sha256:56d66ba010a67f0668f301984204f8e3f0c189bd4cba9ff20ce2289aabf24259

4.6 集群应用客户端管理集群文件准备

[root@k8s-master ~]# mkdir -p $HOME/.kube
[root@k8s-master ~]# cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
[root@k8s-master ~]# chown $(id -u):$(id -g) $HOME/.kube/config
[root@k8s-master ~]# ls /root/.kube/
cache  config

4.7 集群工作节点添加

在所有node节点执行

查询加入节点的命令，在master上执行
# kubeadm token create --print-join-command
kubeadm join 192.168.1.10:6443 --token i3ny5z.bsb1et1pq3lqhj3q --discovery-token-ca-cert-hash sha256:dfd931f4611f565b15776a1640dabc6720b3439812fda367ce856916e8494853

注意需要在最后增加--cri-socket=unix:///var/run/cri-dockerd.sock
# kubeadm join 192.168.1.10:6443 --token gkamdx.tt7grt6dc4vw8352 \
        --discovery-token-ca-cert-hash sha256:d543c10aaf935bcbcb03da989055f2054e6fc35af7bb3f3acf35b957a4e761c8 --cri-socket=unix:///var/run/cri-dockerd.sock

5. 部署容器网络

在所有node节点执行

5.1 准备calico安装

下载calico资源清单文件，注意可能需要科学上网
# wget https://projectcalico.docs.tigera.io/archive/v3.25/manifests/calico.yaml

5.2 安装calico

应用资源清单文件，创建calico
# kubectl apply -f calico.yaml
查看kube-system命名空间中coredns状态，处于Running状态表明联网成功。
[root@k8s-master1 ~]# kubectl get pods -n kube-system
NAME                                       READY   STATUS    RESTARTS   AGE
calico-kube-controllers-6c99c8747f-rvzds   1/1     Running   0          4m13s
calico-node-f7b9l                          1/1     Running   0          4m13s
coredns-7bdc4cb885-8z2fz                   1/1     Running   0          18m
coredns-7bdc4cb885-gmpd7                   1/1     Running   0          18m
etcd-k8s-master                            1/1     Running   0          19m
kube-apiserver-k8s-master                  1/1     Running   0          19m
kube-controller-manager-k8s-master         1/1     Running   0          19m
kube-proxy-hs5sg                           1/1     Running   0          18m
kube-scheduler-k8s-master                  1/1     Running   0          19m

6. 验证集群可用性

查看所有的节点
[root@k8s-master ~]# kubectl get nodes -owide
NAME         STATUS   ROLES           AGE   VERSION   INTERNAL-IP     EXTERNAL-IP   OS-IMAGE                KERNEL-VERSION               CONTAINER-RUNTIME
k8s-master   Ready    control-plane   19m   v1.27.0   192.168.1.10   <none>        CentOS Linux 7 (Core)   6.2.11-1.el7.elrepo.x86_64   docker://23.0.3
k8s-node1    Ready    control-plane   19m   v1.27.0   192.168.1.11   <none>        CentOS Linux 7 (Core)   6.2.11-1.el7.elrepo.x86_64   docker://23.0.3
k8s-node2    Ready    control-plane   19m   v1.27.0   192.168.1.12   <none>        CentOS Linux 7 (Core)   6.2.11-1.el7.elrepo.x86_64   docker://23.0.3
查看集群健康情况
[root@k8s-master ~]# 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","reason":""}

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7. K8S安装 Dashboard

7.1 概述

Dashboard 是基于网页的 Kubernetes 用户界面。你可以使用 Dashboard 将容器应用部署到 Kubernetes 集群中，也可以对容器应用排错，还能管理集群资源。你可以使用 Dashboard 获取运行在集群中的应用的概览信息，也可以创建或者修改 Kubernetes 资源（如 Deployment，Job，DaemonSet 等等）。但是一般还是图形化界面一般还是给开发或者对kubernetes不太熟悉的人查看使用。

7.2Kubernetes-Dashboard安装

下载地址：参考 Kubernetes-Dashboard

mkdir -p /etc/kubernetes/dashboard
cd /etc/kubernetes/dashboard
wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.7.0/aio/deploy/recommended.yaml

7.3 修改 recommended.yaml

#修改 recommended.yaml中service的相关部分，可以临时使用nodeport的方式访问

  # Adde by How
    type: NodePort
-----------------------------------------------------------------------------------
kind: Service
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
spec:
  type: NodePort      #修改文件，增加nodeport参数便于访问
  ports:
    - port: 443
      targetPort: 8443
      nodePort: 32641  #指定nodePort,这样当集群重启时端口不会变更了。
  selector:
    k8s-app: kubernetes-dashboard

7.4 执行安装

[root@master01]# kubectl apply -f recommended.yaml
-------------------output------------------------------------------------
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

7.5 查看服务是否正常运行

[root@master01 dashboard]# kubectl -n kubernetes-dashboard get pods
NAME                                         READY   STATUS    RESTARTS   AGE
dashboard-metrics-scraper-5cb4f4bb9c-dmkrb   1/1     Running   0          176m
kubernetes-dashboard-6967859bff-9n966        1/1     Running   0          176m


-----------------------------------------------------------------------------------


[root@master01 tools]# kubectl -n kubernetes-dashboard get service kubernetes-dashboard
NAME                   TYPE       CLUSTER-IP      EXTERNAL-IP   PORT(S)         AGE
kubernetes-dashboard   NodePort   10.106.206.69   <none>        443:32641/TCP   71m

用浏览器访问控制台

访问 https://192.168.1.10:32641 即可进入控制台界面

注意：Chrome如果提示不安全连接,并且高级选项也无法进入, 在页面空白处键入 thisisunsafe 即可

7.6 访问控制

有好几种方式,这里只选择了token方式

1. 创建管理员服务帐号

mkdir -p /etc/kubernetes/dashboard
cd /etc/kubernetes/dashboard
vim admin-user.yaml

7.6.1 创建管理员用户

首先创建一个叫admin-user的服务账号，并放在kubernetes-dashboard名称空间下：

#vim admin-user.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
  name: admin-user
  namespace: kubernetes-dashboard
  
 # kubectl apply -f admin-user.yaml

7.6.2 绑定管理员集群角色

默认情况下，kubeadm创建集群时已经创建了cluster-admin角色，我们直接绑定即可

#cd /etc/kubernetes/dashboard
#vim admin-user-role-binding.yaml

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: admin-user
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: admin-user
  namespace: kubernetes-dashboard
  
  #执行配置
  #kubectl apply -f admin-user-role-binding.yaml

7.6.3 创建管理员Token

现在我们创建admin-user用户的Token，以便用来登录dashboard：

cd /etc/kubernetes/dashboard
kubectl -n kubernetes-dashboard create token admin-user
-------------------------------------------------------
此处略

7.6.4 用管理员token登陆

把Token复制到登录界面的Token输入框中登陆 https://192.168.1.10:32641「输入master地址或者node地址都可以」正常登陆

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7.6.5 Kubernetes Dashboard token失效时间设置

Dashboard的Token失效时间可以通过 token-ttl 参数来设置，这里我们有三种方式：【yaml、直接修改、通过Kubernetes Dashboard 】

我们这边通过kubectl 直接修改

#kubectl edit deployment kubernetes-dashboard -n kube-system
------------------------------------------------
spec:
      containers:
      - args:
        - --auto-generate-certificates
        - --token-ttl=43200  
        - --namespace=kubernetes-dashboard
        image: kubernetesui/dashboard:v2.7.0
        imagePullPolicy: Always
        livenessProbe:
          failureThreshold: 3
          httpGet:
            path: /
            port: 8443
            scheme: HTTPS
          initialDelaySeconds: 30
          periodSeconds: 10
          successThreshold: 1
          timeoutSeconds: 30
        name: kubernetes-dashboard
        ports:

参数名	默认值	说明
token-ttl	15 分钟	仪表板生成的JWE令牌的过期时间（秒）。默认值：15分钟0-永不过期。

常见问题：

一、CentOS7添加 net.bridge.bridge-nf-call-iptables 出现No such file or directory

1、问题
[root@master01 ~]# sysctl -p /etc/sysctl.d/k8s.conf
sysctl: cannot stat /proc/sys/net/bridge/bridge-nf-call-ip6tables: No such file or directory
sysctl: cannot stat /proc/sys/net/bridge/bridge-nf-call-iptables: No such file or directory

解决：
#  modprobe br_netfilter

#  ls /proc/sys/net/bridge
bridge-nf-call-arptables  bridge-nf-call-iptables        bridge-nf-filter-vlan-tagged
bridge-nf-call-ip6tables  bridge-nf-filter-pppoe-tagged  bridge-nf-pass-vlan-input-dev

#  sysctl -p
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-iptables = 1
net.bridge.bridge-nf-call-ip6tables = 1

二、测试k8s集群

[root@master01 ~]# kubectl create deployment nginx --image=nginx
deployment.apps/nginx created
[root@master01 ~]# kubectl expose deployment nginx --port=80  --type=NodePort
service/nginx exposed
[root@master01 ~]# kubectl get pod,svc
NAME                         READY   STATUS             RESTARTS   AGE
pod/nginx-85b98978db-2lsms   0/1     ImagePullBackOff   0          32s

NAME                 TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)        AGE
service/kubernetes   ClusterIP   10.96.0.1      <none>        443/TCP        21h
service/nginx        NodePort    10.96.20.147   <none>        80:30536/TCP   8s