kubernates集群搭建

用户1215919

发布于 2021-12-28 12:48:33

3230

发布于 2021-12-28 12:48:33

文章被收录于专栏：大大的微笑大大的微笑

版本

CentOS7
Docker 18.09.0
kubeadm-1.14.0-0
kubelet-1.14.0-0
kubectl-1.14.0-0
calico:v3.9

依赖更新及安装

yum -y update
yum install -y conntrack ipvsadm ipset jq sysstat curl iptables libseccomp

docker安装

上一篇写的docker的博客内容：

https://cloud.tencent.com/developer/article/1926368

配置hosts文件

# 设置master的hostname，并且修改hosts文件
sudo hostnamectl set-hostname m
#两个slave
sudo hostnamectl set-hostname w1
sudo hostnamectl set-hostname w2

# vi /etc/hosts(三台节点都配置一下)
master的ip m
slave1的ip w1
slave2的ip w2
# 测试
ping m
ping w1
ping w2

系统基础配置

# 关闭防火墙
systemctl stop firewalld && systemctl disable firewalld
# 关闭selinux
setenforce 0
sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config
# 关闭swap
swapoff -a
sed -i '/swap/s/^\(.*\)$/#\1/g' /etc/fstab
# 配置iptables的ACCEPT规则
	iptables -F && iptables -X && iptables \
    -F -t nat && iptables -X -t nat && iptables -P FORWARD ACCEPT
# 设置系统参数
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kubeadm, kubelet及kubectl

配置yum源

cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
       http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF

安装kubeadm&kubelet&kubectl

yum install -y kubeadm-1.14.0-0 kubelet-1.14.0-0 kubectl-1.14.0-0

注意

#因为我这边报了如下错误，所以还需要安装: kubernetes-cni- 0.7.5：
Error: Package: kubelet-1.14.0-0.x86_64 (kubernetes)
           Requires: kubernetes-cni = 0.7.5
           Available: kubernetes-cni-0.3.0.1-0.07a8a2.x86_64 (kubernetes)
               kubernetes-cni = 0.3.0.1-0.07a8a2
           Available: kubernetes-cni-0.5.1-0.x86_64 (kubernetes)
               kubernetes-cni = 0.5.1-0
           Available: kubernetes-cni-0.5.1-1.x86_64 (kubernetes)
               kubernetes-cni = 0.5.1-1
           Available: kubernetes-cni-0.6.0-0.x86_64 (kubernetes)
               kubernetes-cni = 0.6.0-0
           Available: kubernetes-cni-0.7.5-0.x86_64 (kubernetes)
               kubernetes-cni = 0.7.5-0
           Available: kubernetes-cni-0.8.6-0.x86_64 (kubernetes)
               kubernetes-cni = 0.8.6-0
           Installing: kubernetes-cni-0.8.7-0.x86_64 (kubernetes)
               kubernetes-cni = 0.8.7-0
 You could try using --skip-broken to work around the problem
 You could try running: rpm -Va --nofiles --nodigest

但是，如果单独安装kubernetes-cni- 0.7.5之后，继续执行的话会发现又有其他的错误如下所示，始终版本不一致，但是我安装的时候明明指定了1.14.0的版本,反反复复检查之后发现原来直接安装kubernetes-cni- 0.7.5的时候会默认给你安装kubelet,显然不是我们想要的结果：

the kubelet version is higher than the control plane version. 
This is not a supportted version skew 
and may lead to a malfunctional cluster.
kubelet v1.9.3， control plane 1.14.0，

如果出现上述问题请执行

yum install -y kubeadm-1.14.0-0 kubelet-1.14.0-0 kubectl-1.14.0-0  kubernetes-cni-0.7.5

systemctl restart docker

systemctl enable kubelet && systemctl start kubelet

查看kubeadm使用的镜像

kubeadm config images list

解决国外镜像不能访问的问题

vi kubeadm.sh
---------------------------
#!/bin/bash
set -e
KUBE_VERSION=v1.14.0
KUBE_PAUSE_VERSION=3.1
ETCD_VERSION=3.3.10
CORE_DNS_VERSION=1.3.1
GCR_URL=k8s.gcr.io
ALIYUN_URL=registry.cn-hangzhou.aliyuncs.com/google_containers
images=(kube-proxy:${KUBE_VERSION}
kube-scheduler:${KUBE_VERSION}
kube-controller-manager:${KUBE_VERSION}
kube-apiserver:${KUBE_VERSION}
pause:${KUBE_PAUSE_VERSION}
etcd:${ETCD_VERSION}
coredns:${CORE_DNS_VERSION})
for imageName in ${images[@]} ; do
	docker pull $ALIYUN_URL/$imageName
	docker tag  $ALIYUN_URL/$imageName $GCR_URL/$imageName
	docker rmi $ALIYUN_URL/$imageName
done

运行脚本并查看镜像

sh ./kubeadm.sh

docker images

初始化master

kubeadm init --kubernetes-version=1.14.0 \
    --apiserver-advertise-address=master IP \
    --pod-network-cidr=10.244.0.0/16

出现如下内容则表示初始化成功

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 xxxxxxx:6443 --token xxxxxx \
    --discovery-token-ca-cert-hash sha256:xxxxxxxxxxxxx

根据日志提示依次执行

mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

查看pod

kubectl get pods -n kube-system

可以看到coredns一直处于pending状态，这是因为还未安装网络插件

calico网络插件（也可以选择其他官方推荐的）

docker pull calico/cni:v3.9.3
docker pull calico/pod2daemon-flexvol:v3.9.3
docker pull calico/node:v3.9.3
docker pull calico/kube-controllers:v3.9.3

可能会因为网络的原因导致失败，可以配置国内镜像地址

slave节点依次执行master初始化得到的内容

kubeadm join xxxxxxx:6443 --token xxxxxx \
    --discovery-token-ca-cert-hash sha256:xxxxxxxxxxxxx

直接执行可能会出现如下内容，执行kubeadm reset再操作即可

[preflight] Running pre-flight checks
error execution phase preflight: [preflight] Some fatal errors occurred:
	[ERROR FileAvailable--etc-kubernetes-bootstrap-kubelet.conf]: /etc/kubernetes/bootstrap-kubelet.conf already exists
	[ERROR FileAvailable--etc-kubernetes-pki-ca.crt]: /etc/kubernetes/pki/ca.crt already exists
[preflight] If you know what you are doing, you can make a check non-fatal with `--ignore-preflight-errors=...`