一、kubeadm 部署 K8S 集群架構
| 主機名 | IP地址 | 安裝組件 |
| master（2C/4G，cpu核心數要求大於2） | 192.168.237.70 | docker、kubeadm、kubelet、kubectl、flannel |
| node01（2C/2G） | 192.168.237.80 | docker、kubeadm、kubelet、kubectl、flannel |
| node02（2C/2G） | 192.168.237.90 | docker、kubeadm、kubelet、kubectl、flannel |
| Harbor節點（hub.lsq.com） | 192.168.237.66 | docker、docker-compose、harbor-offline-v1.2.2 |
部署的總體步驟如下：
1、在所有節點上安裝Docker和kubeadm
2、部署Kubernetes Master
3、部署容器網絡插件
4、部署 Kubernetes Node，將節點加入Kubernetes集群中
5、部署 Dashboard Web 頁面，可視化查看Kubernetes資源
6、部署 Harbor 私有倉庫，存放鏡像資源
1、環境准備
//所有節點，關閉防火牆規則，關閉selinux，關閉swap交換
systemctl stop firewalld
systemctl disable firewalld
setenforce 0
iptables -F && iptables -t nat -F && iptables -t mangle -F && iptables -X
swapoff -a #交換分區必須要關閉
sed -ri 's/.*swap.*/#&/' /etc/fstab #永久關閉swap分區，&符號在sed命令中代表上次匹配的結果
#加載 ip_vs 模塊
for i in $(ls /usr/lib/modules/$(uname -r)/kernel/net/netfilter/ipvs|grep -o "^[^.]*");do echo $i; /sbin/modinfo -F filename $i >/dev/null 2>&1 && /sbin/modprobe $i;done
//修改主機名
hostnamectl set-hostname master
hostnamectl set-hostname node1
hostnamectl set-hostname node2
//所有節點修改hosts文件
vim /etc/hosts
192.168.237.70 master
192.168.237.80 node1
192.168.237.90 node2
//調整內核參數
cat > /etc/sysctl.d/kubernetes.conf << EOF
#開啟網橋模式，可將網橋的流量傳遞給iptables鏈
net.bridge.bridge-nf-call-ip6tables=1
net.bridge.bridge-nf-call-iptables=1
#關閉ipv6協議
net.ipv6.conf.all.disable_ipv6=1
net.ipv4.ip_forward=1
EOF
//生效參數
sysctl --system
2、所有節點安裝docker
yum install -y yum-utils device-mapper-persistent-data lvm2
yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
yum install -y docker-ce docker-ce-cli containerd.io
mkdir /etc/docker
cat > /etc/docker/daemon.json <<EOF
{
"registry-mirrors": ["https://6ijb8ubo.mirror.aliyuncs.com"],
"exec-opts": ["native.cgroupdriver=systemd"],
"log-driver": "json-file",
"log-opts": {
"max-size": "100m"
}
}
EOF
#使用Systemd管理的Cgroup來進行資源控制與管理，因為相對Cgroupfs而言，Systemd限制CPU、內存等資源更加簡單和成熟穩定。
#日志使用json-file格式類型存儲，大小為100M，保存在/var/log/containers目錄下，方便ELK等日志系統收集和管理日志。
systemctl daemon-reload
systemctl restart docker.service
systemctl enable docker.service
docker info | grep "Cgroup Driver"
Cgroup Driver: systemd//采用shell腳本安裝docker並傳到其它主機上運行
vim docker.sh
#!/bin/bash
yum install -y yum-utils device-mapper-persistent-data lvm2
yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
yum install -y docker-ce docker-ce-cli containerd.io
mkdir -p /etc/docker
tee /etc/docker/daemon.json <<-'EOF'
{
"registry-mirrors": ["https://qn26bytm.mirror.aliyuncs.com"],
"exec-opts": ["native.cgroupdriver=systemd"],
"log-driver": "json-file",
"log-opts": {
"max-size": "100m"
}
}
EOF
systemctl daemon-reload
systemctl restart docker.service
systemctl enable docker.service
docker info | grep "Cgroup Driver"
chmod +x docker.sh
scp docker.sh root@192.168.237.80:/root/
scp docker.sh root@192.168.237.90:/root/
scp docker.sh root@192.168.237.66:/root/
3、所有節點安裝kubeadm，kubelet和kubectl
//定義kubernetes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
yum install -y kubelet-1.15.1 kubeadm-1.15.1 kubectl-1.15.1
//開機自啟kubelet
systemctl enable kubelet.service
#K8S通過kubeadm安裝出來以后都是以Pod方式存在，即底層是以容器方式運行，所以kubelet必須設置開機自啟
3、部署K8S集群
//查看初始化需要的鏡像
kubeadm config images list
//在 master 節點上傳 kubeadm-basic.images.tar.gz 壓縮包至 /opt 目錄
cd /opt
tar zxvf kubeadm-basic.images.tar.gz
for i in $(ls /opt/kubeadm-basic.images/*.tar); do docker load -i $i; done
//復制鏡像和腳本到 node 節點，並在 node 節點上執行腳本 bash /opt/load-images.sh
scp -r kubeadm-basic.images root@node1:/opt
scp -r kubeadm-basic.images root@node2:/opt
//初始化kubeadm
方法一：
kubeadm config print init-defaults > /opt/kubeadm-config.yaml
cd /opt/
vim kubeadm-config.yaml
......
11 localAPIEndpoint:
12 advertiseAddress: 192.168.237.70 #指定master節點的IP地址
13 bindPort: 6443
......
34 kubernetesVersion: v1.15.1 #指定kubernetes版本號
35 networking:
36 dnsDomain: cluster.local
37 podSubnet: "10.244.0.0/16" #指定pod網段，10.244.0.0/16用於匹配flannel默認網段
38 serviceSubnet: 10.96.0.0/16 #指定service網段
39 scheduler: {}
--- #末尾再添加以下內容
apiVersion: kubeproxy.config.k8s.io/v1alpha1
kind: KubeProxyConfiguration
mode: ipvs #把默認的service調度方式改為ipvs模式
kubeadm init --config=kubeadm-config.yaml --experimental-upload-certs | tee kubeadm-init.log
#--experimental-upload-certs 參數可以在后續執行加入節點時自動分發證書文件，k8sV1.16版本開始替換為 --upload-certs
#tee kubeadm-init.log 用以輸出日志
//查看 kubeadm-init 日志
less kubeadm-init.log
//kubernetes配置文件目錄
ls /etc/kubernetes/
//存放ca等證書和密碼的目錄
ls /etc/kubernetes/pki
方法二：
kubeadm init \
--apiserver-advertise-address=0.0.0.0 \
--image-repository registry.aliyuncs.com/google_containers \
--kubernetes-version=v1.15.1 \
--service-cidr=10.1.0.0/16 \
--pod-network-cidr=10.244.0.0/16
---------------------------------------------------------------------------------
初始化集群需使用kubeadm init命令，可以指定具體參數初始化，也可以指定配置文件初始化。
可選參數：
--apiserver-advertise-address：apiserver通告給其他組件的IP地址，一般應該為Master節點的用於集群內部通信的IP地址，0.0.0.0表示節點上所有可用地址
--apiserver-bind-port：apiserver的監聽端口，默認是6443
--cert-dir：通訊的ssl證書文件，默認/etc/kubernetes/pki
--control-plane-endpoint：控制台平面的共享終端，可以是負載均衡的ip地址或者dns域名，高可用集群時需要添加
--image-repository：拉取鏡像的鏡像倉庫，默認是k8s.gcr.io
--kubernetes-version：指定kubernetes版本
--pod-network-cidr：pod資源的網段，需與pod網絡插件的值設置一致。通常，Flannel網絡插件的默認為10.244.0.0/16，Calico插件的默認值為192.168.0.0/16；
--service-cidr：service資源的網段
--service-dns-domain：service全域名的后綴，默認是cluster.local
---------------------------------------------------------------------------------------------
方法二初始化后需要修改 kube-proxy 的 configmap，開啟 ipvs
kubectl edit cm kube-proxy -n=kube-system
修改mode: ipvs
cat /opt/kubeadm-init.log
提示：
......
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) $HOME/.kube/config
You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
https://kubernetes.io/docs/concepts/cluster-administration/addons/
Then you can join any number of worker nodes by running the following on each as root:
kubeadm join 192.168.237.70:6443 --token abcdef.0123456789abcdef \
--discovery-token-ca-cert-hash sha256:a871cac375442dffc008604eb49d50381f573a2ecea31d3dec4b1dda156fc798
//設定kubectl
kubectl需經由API server認證及授權后方能執行相應的管理操作，kubeadm 部署的集群為其生成了一個具有管理員權限的認證配置文件 /etc/kubernetes/admin.conf，它可由 kubectl 通過默認的 “$HOME/.kube/config” 的路徑進行加載。
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
//在 node 節點上執行 kubeadm join 命令加入群集
kubeadm join 192.168.80.10:6443 --token rc0kfs.a1sfe3gl4dvopck5 \
--discovery-token-ca-cert-hash sha256:864fe553c812df2af262b406b707db68b0fd450dc08b34efb73dd5a4771d37a2
//所有節點部署網絡插件flannel
方法一：
//所有節點上傳flannel鏡像 flannel.tar 到 /opt 目錄，master節點上傳 kube-flannel.yml 文件
cd /opt
docker load < flannel.tar
//在 master 節點創建 flannel 資源
kubectl apply -f kube-flannel.yml
方法二：
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
//在master節點查看節點狀態（需要等幾分鍾）
[root@master opt]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master Ready master 44m v1.15.1
node1 Ready <none> 17m v1.15.1
node2 Ready <none> 15m v1.15.1
[root@master opt]# kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
coredns-5c98db65d4-cqm68 1/1 Running 0 5m13s
coredns-5c98db65d4-lm9z5 1/1 Running 0 5m13s
etcd-master 1/1 Running 0 4m28s
kube-apiserver-master 1/1 Running 0 4m13s
kube-controller-manager-master 1/1 Running 0 4m6s
kube-flannel-ds-amd64-7vhjw 1/1 Running 0 23s
kube-flannel-ds-amd64-nhpr4 1/1 Running 0 23s
kube-flannel-ds-amd64-tjnrn 1/1 Running 0 23s
kube-proxy-5pcdb 1/1 Running 0 2m28s
kube-proxy-cxlt2 1/1 Running 0 2m34s
kube-proxy-hbfxc 1/1 Running 0 5m13s
kube-scheduler-master 1/1 Running 0 4m21s
//測試 pod 資源創建
kubectl create deployment nginx --image=nginx
//暴露端口提供服務
kubectl expose deployment nginx --port=80 --type=NodePort
//測試訪問
curl http://node1:32365
//擴展3個副本
kubectl scale deployment nginx --replicas=3
二、dashboard 部署
1、 安裝dashboard
//所有節點安裝dashboard
方法一：
//所有節點上傳dashboard鏡像 dashboard.tar 到 /opt 目錄，master節點上傳kubernetes-dashboard.yaml文件
cd /opt/
docker load < dashboard.tar
kubectl apply -f kubernetes-dashboard.yaml
方法二：
kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0/aio/deploy/recommended.yaml
//查看所有容器運行狀態
kubectl get pods,svc -n kube-system -o wide
[root@master opt]# kubectl get pods,svc -n kube-system -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod/coredns-5c98db65d4-cqm68 1/1 Running 0 25m 10.244.2.3 node2 <none> <none>
pod/coredns-5c98db65d4-lm9z5 1/1 Running 0 25m 10.244.2.2 node2 <none> <none>
pod/etcd-master 1/1 Running 0 24m 192.168.237.70 master <none> <none>
pod/kube-apiserver-master 1/1 Running 0 24m 192.168.237.70 master <none> <none>
pod/kube-controller-manager-master 1/1 Running 0 24m 192.168.237.70 master <none> <none>
pod/kube-flannel-ds-amd64-7vhjw 1/1 Running 0 20m 192.168.237.70 master <none> <none>
pod/kube-flannel-ds-amd64-nhpr4 1/1 Running 0 20m 192.168.237.90 node2 <none> <none>
pod/kube-flannel-ds-amd64-tjnrn 1/1 Running 0 20m 192.168.237.80 node1 <none> <none>
pod/kube-proxy-5pcdb 1/1 Running 0 22m 192.168.237.90 node2 <none> <none>
pod/kube-proxy-cxlt2 1/1 Running 0 22m 192.168.237.80 node1 <none> <none>
pod/kube-proxy-hbfxc 1/1 Running 0 25m 192.168.237.70 master <none> <none>
pod/kube-scheduler-master 1/1 Running 0 24m 192.168.237.70 master <none> <none>
pod/kubernetes-dashboard-859b87d4f7-n6d4w 1/1 Running 0 2m5s 10.244.2.5 node2 <none> <none>
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
service/kube-dns ClusterIP 10.96.0.10 <none> 53/UDP,53/TCP,9153/TCP 25m k8s-app=kube-dns
service/kubernetes-dashboard NodePort 10.98.0.246 <none> 443:30001/TCP 2m5s k8s-app=kubernetes-dashboard
[root@master opt]# 
2、使用火狐或者360瀏覽器訪問
https://node1:30001/
https://192.168.237.70:30001/
//創建service account並綁定默認cluster-admin管理員集群角色
kubectl create serviceaccount dashboard-admin -n kube-system
kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kube-system:dashboard-admin
//獲取令牌密鑰
kubectl describe secrets -n kube-system $(kubectl -n kube-system get secret | awk '/dashboard-admin/{print $1}')
[root@master opt]# kubectl describe secrets -n kube-system $(kubectl -n kube-system get secret | awk '/dashboard-admin/{print $1}')
Name: dashboard-admin-token-sh894
Namespace: kube-system
Labels: <none>
Annotations: kubernetes.io/service-account.name: dashboard-admin
kubernetes.io/service-account.uid: 9432d230-d619-4c20-ad2e-ce976184a902
Type: kubernetes.io/service-account-token
Data
====
ca.crt: 1025 bytes
namespace: 11 bytes
token: eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.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.SPnRfLYyRDyLKni5TJuiwLNds-kA30rr40eeW09oPRAUOKCek1ot0UHL-vc-f4eyVozw7YIuivJinngIMQ9WvuDVcKbfT2Qoh87Tjff01XN0nRlWlwj5ICqpQPHj6141rZgkWBNlmxYbpnu0TtKB71zNSwOJiCfOqSIr8dqBQFvjVTLmfHC_ghowyiyTN10FXFlaf_I-q9P9zyKwM47NCklURnI6wnDzCa77lURRVGJCT27ScBo3KfKt9yGuRs4FjgQbJyVtRU-CITdJrbTTXYB1lca-8PX5B_4SrjbPMJfMUdn9QCNvGgXOJPOQuVV1u8wmbw5qU8izc3b5LjgeIw
//復制token令牌直接登錄網站
三 、安裝Harbor私有倉庫
//修改主機名
hostnamectl set-hostname hub.lsq.com
//所有節點加上主機名映射
echo '192.168.237.66 hub.lsq.com' >> /etc/hosts
//安裝 docker
yum install -y yum-utils device-mapper-persistent-data lvm2
yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
yum install -y docker-ce docker-ce-cli containerd.io
mkdir /etc/docker
cat > /etc/docker/daemon.json <<EOF
{
"registry-mirrors": ["https://qn26bytm.mirror.aliyuncs.com"],
"exec-opts": ["native.cgroupdriver=systemd"],
"log-driver": "json-file",
"log-opts": {
"max-size": "100m"
},
"insecure-registries": ["https://hub.lsq.com"]
}
EOF
systemctl start docker
systemctl enable docker
//所有節點都修改 docker 配置文件，加上私有倉庫配置
cat > /etc/docker/daemon.json <<EOF
{
"registry-mirrors": ["https://qn26bytm.mirror.aliyuncs.com"],
"exec-opts": ["native.cgroupdriver=systemd"],
"log-driver": "json-file",
"log-opts": {
"max-size": "100m"
},
"insecure-registries": ["https://hub.lsq.com"]
}
EOF
systemctl daemon-reload
systemctl restart docker
//上傳 harbor-offline-installer-v1.2.2.tgz 和 docker-compose 文件到 /opt 目錄
cd /opt
cp docker-compose /usr/local/bin/
chmod +x /usr/local/bin/docker-compose
tar zxvf harbor-offline-installer-v1.2.2.tgz
cd harbor/
vim harbor.cfg
5 hostname = hub.lsq.com
9 ui_url_protocol = https
24 ssl_cert = /data/cert/server.crt
25 ssl_cert_key = /data/cert/server.key
59 harbor_admin_password = Harbor12345
//生成證書
mkdir -p /data/cert
cd /data/cert
#生成私鑰
openssl genrsa -des3 -out server.key 2048
輸入兩遍密碼：123456
#生成證書簽名請求文件
openssl req -new -key server.key -out server.csr
輸入私鑰密碼：123456
輸入國家名：CN
輸入省名：BJ
輸入市名：BJ
輸入組織名：KGC
輸入機構名：KGC
輸入域名：hub.lsq.com
輸入管理員郵箱：admin@lsq.com
其它全部直接回車
#備份私鑰
cp server.key server.key.org
#清除私鑰密碼
openssl rsa -in server.key.org -out server.key
輸入私鑰密碼：123456
#簽名證書
openssl x509 -req -days 1000 -in server.csr -signkey server.key -out server.crt
chmod +x /data/cert/*
cd /opt/harbor/
./install.sh
瀏覽器訪問：https://hub.lsq.com
用戶名：admin
密碼：Harbor12345
//在一個node節點上登錄harbor
docker login -u admin -p Harbor12345 https://hub.lsq.com
//上傳鏡像
docker tag nginx:latest hub.lsq.com/library/nginx:v1
docker push hub.lsq.com/library/nginx:v1
//在master節點上刪除之前創建的nginx資源
kubectl delete deployment nginx
kubectl run nginx-deployment --image=hub.lsq.com/library/nginx:v1 --port=80 --replicas=3
kubectl expose deployment nginx-deployment --port=30000 --target-port=80
kubectl get svc,pods
yum install ipvsadm -y
ipvsadm -Ln
curl 10.96.222.161:30000
kubectl edit svc nginx-deployment
25 type: NodePort #把調度策略改成NodePort
kubectl get svc
//kubectl get svc瀏覽器訪問：
192.168.237.70:31118
192.168.237.80:31118
192.168.237.90:31118
四、內核參數優化方案
cat > /etc/sysctl.d/kubernetes.conf <<EOF
net.bridge.bridge-nf-call-iptables=1
net.bridge.bridge-nf-call-ip6tables=1
net.ipv4.ip_forward=1
net.ipv4.tcp_tw_recycle=0
vm.swappiness=0 #禁止使用 swap 空間，只有當系統內存不足（OOM）時才允許使用它
vm.overcommit_memory=1 #不檢查物理內存是否夠用
vm.panic_on_oom=0 #開啟 OOM
fs.inotify.max_user_instances=8192
fs.inotify.max_user_watches=1048576
fs.file-max=52706963 #指定最大文件句柄數
fs.nr_open=52706963 #僅4.4以上版本支持
net.ipv6.conf.all.disable_ipv6=1
net.netfilter.nf_conntrack_max=2310720
EOF