一、节点规划
主机名 | 主机IP |
---|---|
k8s-master | 172.17.185.91 |
k8s-node01 | 172.17.185.92 |
k8s-node02 | 172.17.185.93 |
k8s-node03 | 172.17.185.94 |
二、所有节点操作
1、关闭防火墙及selinux
systemctl stop firewalld && systemctl disable firewalld
sed -i 's/^SELINUX=.*/SELINUX=disabled/' /etc/selinux/config && setenforce 0
2、关闭 swap 分区
# 临时
swapoff -a
#永久
sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab
3、设置主机名
# 在172.17.185.91主机执行
hostnamectl set-hostname k8s-master
# 在172.17.185.92主机执行
hostnamectl set-hostname k8s-node01
# 在172.17.185.93主机执行
hostnamectl set-hostname k8s-node02
# 在172.17.185.94主机执行
hostnamectl set-hostname k8s-node03
4、配置本地域名解析
cat > /etc/hosts <<EOF
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
172.17.185.91 k8s-master
172.17.185.92 k8s-node01
172.17.185.93 k8s-node02
172.17.185.94 k8s-node03
EOF
5、将桥接的IPv4流量传递到iptables的链
cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl --system
6、时间同步配置
yum install -y ntpdate
为保证节点的时间请保持一致,在crontab中配置:
(echo "*/5 * * * * /usr/sbin/ntpdate -u cn.pool.ntp.org") | crontab
systemctl restart crond
7、安装docker
# 安装yum源
yum -y install yum-utils
yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
# 安装最新的docker软件包
yum -y install docker-ce
# 配置docker仓库源地址
mkdir -p /etc/docker/
cat > /etc/docker/daemon.json <<EOF
{
"registry-mirrors":[
"https://docker.mirrors.ustc.edu.cn",
"http://hub-mirror.c.163.com"
]
}
EOF
# 启动并查看docker服务
systemctl enable docker && systemctl start docker
8、添加kubernetes的阿里YUM软件源
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
9、所有主机安装kubeadm,kubelet和kubectl
yum install -y kubelet-1.18.0 kubeadm-1.18.0 kubectl-1.18.0
systemctl enable kubelet
三、部署Kubernetes Master
本章节只需要在Master节点执行。
1、使用kubeadm部署master节点
kubeadm init \
--apiserver-advertise-address=172.17.185.91 \
--image-repository registry.aliyuncs.com/google_containers \
--kubernetes-version v1.18.0 \
--service-cidr=10.1.0.0/16 \
--service-cidr=10.10.0.0/16 \
--pod-network-cidr=10.122.0.0/16
说明:(1)由于默认拉取镜像地址k8s.gcr.io国内无法访问,这里指定阿里云镜像仓库地址。(2) apiserver-advertise-address需要修改成自己的master地址。(3)当命令执行错误机器时,可用命令kubeadm reset
对节点进行恢复
W1019 11:38:39.482069 2578 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
[WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/
[WARNING Service-Kubelet]: kubelet service is not enabled, please run 'systemctl enable kubelet.service'
[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 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.10.0.1 172.17.185.91]
[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 [172.17.185.91 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [k8s-master localhost] and IPs [172.17.185.91 127.0.0.1 ::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"
W1019 11:39:33.273004 2578 manifests.go:225] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[control-plane] Creating static Pod manifest for "kube-scheduler"
W1019 11:39:33.273620 2578 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 21.005309 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 k8s-master as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node k8s-master as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: nofewt.tgotrk7m72yjnxwz
[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 172.17.185.91:6443 --token nofewt.tgotrk7m72yjnxwz \
--discovery-token-ca-cert-hash sha256:57f15cdef16774b7f4089a4f2b09410c7c52631ead802f59a646e89edb76bd0d
根据输出提示操作:
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
2、安装calico网络
说明:尝试网上的安装flannel网络时会被墙。
kubectl apply -f https://docs.projectcalico.org/manifests/calico.yaml
四、加入Kubernetes Node
本章在两个 Node 节点执行。
使用kubeadm join 注册Node节点到Matser,kubeadm join 的内容,在上面kubeadm init 已经生成好了
# 在172.17.185.92主机执行
kubeadm join 172.17.185.91:6443 --token nofewt.tgotrk7m72yjnxwz \
--discovery-token-ca-cert-hash sha256:57f15cdef16774b7f4089a4f2b09410c7c52631ead802f59a646e89edb76bd0d
# 在172.17.185.93主机执行
kubeadm join 172.17.185.91:6443 --token nofewt.tgotrk7m72yjnxwz \
--discovery-token-ca-cert-hash sha256:57f15cdef16774b7f4089a4f2b09410c7c52631ead802f59a646e89edb76bd0d
# 在172.17.185.94主机执行
kubeadm join 172.17.185.91:6443 --token nofewt.tgotrk7m72yjnxwz \
--discovery-token-ca-cert-hash sha256:57f15cdef16774b7f4089a4f2b09410c7c52631ead802f59a646e89edb76bd0d
加入node节点后,回到master节点执行:kubectl get nodes ,知道STATUS均为Ready状态时代表集群安装完成。
[root@localhost ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master Ready master 2m54s v1.18.0
k8s-node01 Ready <none> 89s v1.18.0
k8s-node02 Ready <none> 87s v1.18.0
k8s-node03 Ready <none> 84s v1.18.0
五、kubeadm添加新master
首先,在master上生成新的token
# kubeadm token create --print-join-command
W1111 17:50:25.985706 292853 configset.go:202] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]
kubeadm join apiserver.cluster.local:6443 --token sc2ty3.ej38ceisi5lmt9ad --discovery-token-ca-cert-hash sha256:42bf6e526b795854b61b7c0ca875f9a8292b989d44f0f51a4d8dec450711b89e
然后,在master上生成用于新master加入的证书
# kubeadm init phase upload-certs --upload-certs
I1111 17:50:52.634857 293705 version.go:252] remote version is much newer: v1.19.3; falling back to: stable-1.18
W1111 17:50:53.498664 293705 configset.go:202] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]
[upload-certs] Storing the certificates in Secret "kubeadm-certs" in the "kube-system" Namespace
[upload-certs] Using certificate key:
c5c77a2b5989c75c0ec98fae91f771c569e5764523fd8daa102a1cb074c07e2f
最后,添加新master节点,把最会一行加到–control-plane --certificate-key后。
# kubeadm join apiserver.cluster.local:6443 --token sc2ty3.ej38ceisi5lmt9ad \
--discovery-token-ca-cert-hash sha256:42bf6e526b795854b61b7c0ca875f9a8292b989d44f0f51a4d8dec450711b89e \
--control-plane --certificate-key c5c77a2b5989c75c0ec98fae91f771c569e5764523fd8daa102a1cb074c07e2f
六、安装k8s管理工具
1、kuboard
请参考文档:https://www.kuboard.cn/install/install-dashboard.html
2、rancher
docker run -d --privileged --restart=always --name rancher -p 80:80 -p 443:443 rancher/rancher:stable
七、证书过期问题
kubeadm 默认证书为一年,一年过期后,会导致api service不可用,使用过程中会出现:x509: certificate has expired or is not yet valid.
处理方法:[1] https://www.cnblogs.com/skymyyang/p/11093686.html
[2] https://www.kancloud.cn/pshizhsysu/kubernetes/2204250