Linux高级---k8s部署（单manster多node）
Linux高级—k8s部署（单manster多node）
文章目录
- Linux高级---k8s部署（单manster多node）
-
- 一、实验环境
- 二、实验步骤
-
- 1、机器的基本准备
- 2、关闭selinux和firewalld
- 3、升级所有的软件
- 4、安装docker
- 5、配置 Docker使用systemd作为默认Cgroup驱动
- 6、关闭swap分区
- 7、修改hosts文件
- 8、修改内核参数
- 9、安装kubeadm,kubelet和kubectl
- 10、部署Kubernetes Master
- 11、node节点服务器加入k8s集群
- 12、安装网络插件flannel(在master节点执行)
一、实验环境
一个master服务器，三台node服务器
软件： centos7.9 docker
硬件： 2G/2C
我们采用kubeadm方式来安装
二、实验步骤
1、机器的基本准备
修改主机的hostname，设置静态IP
192.168.17.144 scmaster
192.168.17.148 scnode1
192.168.17.149 scnode2
192.168.17.150 scnode3
2、关闭selinux和firewalld
每一台服务器都需要完成
[root@scmaster ~]# service firewalld stop
Redirecting to /bin/systemctl stop firewalld.service
[root@scmaster ~]# systemctl disable firewalld
Removed symlink /etc/systemd/system/multi-user.target.wants/firewalld.service.
Removed symlink /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
[root@scmaster ~]#
[root@scmaster ~]# vim /etc/selinux/config
SELINUX=disabled
[root@scmaster ~]# getenforce
Enforcing
[root@scmaster ~]# setenforce 0
[root@scmaster ~]#
3、升级所有的软件
每一台服务器都需要完成
yum update -y
4、安装docker
每一台服务器都需要完成
1.卸载原来安装过的docker，如果没有安装可以不需要卸载
yum remove docker \
docker-client \
docker-client-latest \
docker-common \
docker-latest \
docker-latest-logrotate \
docker-logrotate \
docker-engine
2.安装yum相关的工具，下载docker-ce.repo文件
[root@cali ~]#
[root@cali ~]# yum install -y yum-utils -y
[root@cali ~]#yum-config-manager \
--add-repo \
https://download.docker.com/linux/centos/docker-ce.repo
下载docker-ce.repo文件存放在/etc/yum.repos.d
[root@cali yum.repos.d]# pwd
/etc/yum.repos.d
[root@cali yum.repos.d]# ls
CentOS-Base.repo CentOS-Debuginfo.repo CentOS-Media.repo CentOS-Vault.repo docker-ce.repo
CentOS-CR.repo CentOS-fasttrack.repo CentOS-Sources.repo CentOS-x86_64-kernel.repo nginx.repo
[root@cali yum.repos.d]#
3.安装docker-ce软件
container engine 容器引擎
docker是一个容器管理的软件
docker-ce 是服务器端软件 server
docker-ce-cli 是客户端软件 client
docker-compose-plugin 是compose插件，用来批量启动很多容器，在单台机器上
containerd.io 底层用来启动容器的
[root@cali yum.repos.d]# yum install docker-ce docker-ce-cli containerd.io docker-compose-plugin -y
[root@scmaster ~]# docker --version
Docker version 20.10.18, build b40c2f6
[root@scmaster ~]#
4.启动docker服务
[root@scmaster ~]# systemctl start docker
[root@scmaster ~]#
[root@scmaster ~]# ps aux|grep docker
root 53288 1.5 2.3 1149960 43264 ? Ssl 15:11 0:00 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock
root 53410 0.0 0.0 112824 984 pts/0 S+ 15:11 0:00 grep --color=auto docker
[root@scmaster ~]#
5.设置docker服务开机启动
[root@scmaster ~]# systemctl enable docker
Created symlink from /etc/systemd/system/multi-user.target.wants/docker.service to /usr/lib/systemd/system/docker.service.
[root@scmaster ~]#
5、配置 Docker使用systemd作为默认Cgroup驱动
每台服务器上都要操作，master和node上都要操作执行下面的脚本，会产生 /etc/docker/daemon.json文件
cat <<EOF > /etc/docker/daemon.json
{
"exec-opts": ["native.cgroupdriver=systemd"]
}
EOF
#重启docker
[root@scmaster docker]# systemctl restart docker
[root@scmaster docker]#
6、关闭swap分区
每一台服务器都需要操作
swapoff -a # 临时关闭
sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab #永久关闭
7、修改hosts文件
每一台服务器都需要操作
[root@scmaster docker]# cat >> /etc/hosts << EOF
> 192.168.227.130 scmaster
> 192.168.227.132 scnode1
> 192.168.227.133 scnode2
> 192.168.227.134 scnode3
> EOF
[root@scmaster docker]# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.227.130 scmaster
192.168.227.132 scnode1
192.168.227.133 scnode2
192.168.227.134 scnode3
[root@scmaster docker]#
8、修改内核参数
每台机器上（master和node），永久修改 追加到内核会读取的参数文件里
[root@scmaster docker]# cat <>/etc/sysctl.conf
> net.bridge.bridge-nf-call-ip6tables = 1
> net.bridge.bridge-nf-call-iptables = 1
> net.ipv4.ip_nonlocal_bind = 1
> net.ipv4.ip_forward = 1
> vm.swappiness=0
> EOF
[root@scmaster docker]# cat /etc/sysctl.conf
# sysctl settings are defined through files in
# /usr/lib/sysctl.d/, /run/sysctl.d/, and /etc/sysctl.d/.
#
# Vendors settings live in /usr/lib/sysctl.d/.
# To override a whole file, create a new file with the same in
# /etc/sysctl.d/ and put new settings there. To override
# only specific settings, add a file with a lexically later
# name in /etc/sysctl.d/ and put new settings there.
#
# For more information, see sysctl.conf(5) and sysctl.d(5).
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1
vm.swappiness=0
[root@scmaster docker]#
让内核重新读取数据，加载生效
[root@scmaster docker]# sysctl -p
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1
vm.swappiness = 0
[root@scmaster docker]#
9、安装kubeadm,kubelet和kubectl
集群里的每台服务器都需要安装
# 添加kubernetes YUM软件源
[root@scmaster docker]# 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
[root@scmaster docker]#yum install -y kubelet-1.23.6 kubeadm-1.23.6 kubectl-1.23.6 --》最好指定版本，因为1.24的版本默认的容器运行时环境不是docker了
[root@scmaster docker]#systemctl enable kubelet
10、部署Kubernetes Master
只在master节点上执行
[root@master ~]# docker pull coredns/coredns:1.8.4
[root@master ~]# docker tag coredns/coredns:1.8.4 registry.aliyuncs.com/google_containers/coredns:v1.8.4
#初始化操作在master服务器上执行
[root@master ~]#kubeadm init \
--apiserver-advertise-address=192.168.17.144 \
--image-repository registry.aliyuncs.com/google_containers \
--service-cidr=10.1.0.0/16 \
--pod-network-cidr=10.244.0.0/16
#192.168.227.130 是master的ip
# --service-cidr string Use alternative range of IP address for service VIPs. (default "10.96.0.0/12") 服务发布暴露--》dnat
# --pod-network-cidr string Specify range of IP addresses for the pod network. If set, the control plane will automatically allocate CIDRs for every node.
[root@scmaster docker]# kubeadm init \
> --apiserver-advertise-address=192.168.17.144 \
> --image-repository registry.aliyuncs.com/google_containers \
> --service-cidr=10.1.0.0/16 \
> --pod-network-cidr=10.244.0.0/16
I0922 16:43:44.828548 53894 version.go:255] remote version is much newer: v1.25.2; falling back to: stable-1.23
[init] Using Kubernetes version: v1.23.12
[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'
[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 [kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local scmaster] and IPs [10.1.0.1 192.168.227.130]
[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 [localhost scmaster] and IPs [192.168.227.130 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [localhost scmaster] and IPs [192.168.227.130 127.0.0.1 ::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"
[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 12.008541 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.23" in namespace kube-system with the configuration for the kubelets in the cluster
NOTE: The "kubelet-config-1.23" naming of the kubelet ConfigMap is deprecated. Once the UnversionedKubeletConfigMap feature gate graduates to Beta the default name will become just "kubelet-config". Kubeadm upgrade will handle this transition transparently.
[upload-certs] Skipping phase. Please see --upload-certs
[mark-control-plane] Marking the node scmaster as control-plane by adding the labels: [node-role.kubernetes.io/master(deprecated) node-role.kubernetes.io/control-plane node.kubernetes.io/exclude-from-external-load-balancers]
[mark-control-plane] Marking the node scmaster as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: ykssm9.g8yfv9rd6avseqnu
[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 192.168.17.144:6443 --token ykssm9.g8yfv9rd6avseqnu \
--discovery-token-ca-cert-hash sha256:e5a34c30d082042dfa876249123502dcddfde7e0695934d70fc41b37889fa0e2
[root@scmaster docker]#
完成初始化的新建文件和目录的操作，在master上完成
[root@scmaster docker]# mkdir -p $HOME/.kube
[root@scmaster docker]# sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
[root@scmaster docker]# sudo chown $(id -u):$(id -g) $HOME/.kube/config
[root@scmaster docker]#
11、node节点服务器加入k8s集群
[root@scnode1 docker]# kubeadm join 192.168.227.130:6443 --token ykssm9.g8yfv9rd6avseqnu \
> --discovery-token-ca-cert-hash sha256:e5a34c30d082042dfa876249123502dcddfde7e0695934d70fc41b37889fa0e2
[preflight] Running pre-flight checks
[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'
[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.
[root@scnode1 docker]#
所有的node节点都需要加入到k8s集群里，查看集群里的机器
[root@scmaster docker]# kubectl get node
NAME STATUS ROLES AGE VERSION
scmaster NotReady control-plane,master 6m38s v1.23.6
scnode1 NotReady <none> 2m22s v1.23.6
scnode2 NotReady <none> 14s v1.23.6
scnode3 NotReady <none> 7s v1.23.6
[root@scmaster docker]#
NotReady 说明master和node节点之间的通信还是有问题的，容器之间通信还没有准备好
12、安装网络插件flannel(在master节点执行)
实现master上的pod和node节点上的pod之间通信
[root@master ~]# cat 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:v0.19.2 for ppc64le and mips64le (dockerhub limitations may apply)
image: docker.io/rancher/mirrored-flannelcni-flannel:v0.19.2
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:v0.19.2 for ppc64le and mips64le (dockerhub limitations may apply)
image: docker.io/rancher/mirrored-flannelcni-flannel:v0.19.2
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
[root@master ~]#
[root@scmaster flannel]# kubectl apply -f kube-flannel.yml
namespace/kube-flannel created
clusterrole.rbac.authorization.k8s.io/flannel created
clusterrolebinding.rbac.authorization.k8s.io/flannel created
serviceaccount/flannel created
configmap/kube-flannel-cfg created
daemonset.apps/kube-flannel-ds created
[root@scmaster flannel]#
[root@scmaster flannel]# kubectl get node
NAME STATUS ROLES AGE VERSION
scmaster Ready control-plane,master 12h v1.23.6
scnode1 Ready <none> 12h v1.23.6
scnode2 Ready <none> 12h v1.23.6
scnode3 Ready <none> 12h v1.23.6