Master节点要部署三个服务：API Server、Scheduler、Controller Manager。
apiserver提供集群管理的REST API接口，包括认证授权、数据校验以 及集群状态变更等
只有API Server才直接操作etcd
其他模块通过API Server查询或修改数据
提供其他模块之间的数据交互和通信的枢纽
scheduler负责分配调度Pod到集群内的node节点
监听kube-apiserver，查询还未分配Node的Pod
根据调度策略为这些Pod分配节点
controller-manager由一系列的控制器组成，它通过apiserver监控整个 集群的状态，并确保集群处于预期的工作状态
1.部署Kubernetes API服务部署
0.准备软件包
cd /usr/local/src/kubernetes cp server/bin/kube-apiserver /opt/kubernetes/bin/ \ cp server/bin/kube-controller-manager /opt/kubernetes/bin/ \ cp server/bin/kube-scheduler /opt/kubernetes/bin/
1.创建生成CSR的 JSON 配置文件
[root@k8s-master kubernetes]# cd /usr/local/src/ssl/ [root@k8s-master ssl]# vim kubernetes-csr.json { "CN": "kubernetes", "hosts": [ "127.0.0.1", "10.0.3.225", #Master IP地址 "10.1.0.1", ？？？ "kubernetes", "kubernetes.default", "kubernetes.default.svc", "kubernetes.default.svc.cluster", "kubernetes.default.svc.cluster.local" ], "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "ST": "BeiJing", "L": "BeiJing", "O": "k8s", "OU": "System" } ] }
2.生成 kubernetes 证书和私钥
cfssl gencert -ca=/opt/kubernetes/ssl/ca.pem \ -ca-key=/opt/kubernetes/ssl/ca-key.pem \ -config=/opt/kubernetes/ssl/ca-config.json \ -profile=kubernetes kubernetes-csr.json | cfssljson -bare kubernetes #拷贝证书到其他节点 cp kubernetes*.pem /opt/kubernetes/ssl/ scp kubernetes*.pem 10.0.3.226:/opt/kubernetes/ssl/ scp kubernetes*.pem 10.0.3.227:/opt/kubernetes/ssl/
3.创建 kube-apiserver 使用的客户端 token 文件
[root@k8s-master ssl]# head -c 16 /dev/urandom | od -An -t x | tr -d ' ' 4c7d89749d1e1a15e5fe55eb5e8446ec [root@k8s-master ssl]# vim /opt/kubernetes/ssl/bootstrap-token.csv 4c7d89749d1e1a15e5fe55eb5e8446ec,kubelet-bootstrap,10001,"system:kubelet-bootstrap"
4.创建基础用户名/密码认证配置
vim /opt/kubernetes/ssl/basic-auth.csv admin,admin,1 readonly,readonly,2
5.部署Kubernetes API Server
vim /usr/lib/systemd/system/kube-apiserver.service [Unit] Description=Kubernetes API Server Documentation=https://github.com/GoogleCloudPlatform/kubernetes After=network.target [Service] ExecStart=/opt/kubernetes/bin/kube-apiserver \ --admission-control=NamespaceLifecycle,LimitRanger,ServiceAccount,DefaultStorageClass,ResourceQuota,NodeRestriction \ --bind-address=10.0.3.225 \ --insecure-bind-address=127.0.0.1 \ --authorization-mode=Node,RBAC \ --runtime-config=rbac.authorization.k8s.io/v1 \ --kubelet-https=true \ --anonymous-auth=false \ --basic-auth-file=/opt/kubernetes/ssl/basic-auth.csv \ --enable-bootstrap-token-auth \ --token-auth-file=/opt/kubernetes/ssl/bootstrap-token.csv \ --service-cluster-ip-range=10.1.0.0/16 \ --service-node-port-range=20000-40000 \ --tls-cert-file=/opt/kubernetes/ssl/kubernetes.pem \ --tls-private-key-file=/opt/kubernetes/ssl/kubernetes-key.pem \ --client-ca-file=/opt/kubernetes/ssl/ca.pem \ --service-account-key-file=/opt/kubernetes/ssl/ca-key.pem \ --etcd-cafile=/opt/kubernetes/ssl/ca.pem \ --etcd-certfile=/opt/kubernetes/ssl/kubernetes.pem \ --etcd-keyfile=/opt/kubernetes/ssl/kubernetes-key.pem \ --etcd-servers=https://10.0.3.225:2379,https://10.0.3.226:2379,https://10.0.3.227:2379 \ --enable-swagger-ui=true \ --allow-privileged=true \ --audit-log-maxage=30 \ --audit-log-maxbackup=3 \ --audit-log-maxsize=100 \ --audit-log-path=/opt/kubernetes/log/api-audit.log \ --event-ttl=1h \ --v=2 \ --logtostderr=false \ --log-dir=/opt/kubernetes/log Restart=on-failure RestartSec=5 Type=notify LimitNOFILE=65536 [Install] WantedBy=multi-user.target
6.启动API Server服务
systemctl daemon-reload systemctl enable kube-apiserver systemctl start kube-apiserver
查看API Server服务状态 systemctl status kube-apiserver
[root@k8s-master ssl]# netstat -lntup|grep kube-apiser
tcp 0 0 10.0.3.225:6443 0.0.0.0:* LISTEN 27784/kube-apiserve
tcp 0 0 127.0.0.1:8080 0.0.0.0:* LISTEN 27784/kube-apiserve
部署ControllerManager服务
刚才安装包已经拷贝过去了，直接配置系统服务即可。
[root@k8s-master ssl]# vim /usr/lib/systemd/system/kube-controller-manager.service [Unit] Description=Kubernetes Controller Manager Documentation=https://github.com/GoogleCloudPlatform/kubernetes [Service] ExecStart=/opt/kubernetes/bin/kube-controller-manager \ --address=127.0.0.1 \ --master=http://127.0.0.1:8080 \ --allocate-node-cidrs=true \ --service-cluster-ip-range=10.1.0.0/16 \ --cluster-cidr=10.2.0.0/16 \ --cluster-name=kubernetes \ --cluster-signing-cert-file=/opt/kubernetes/ssl/ca.pem \ --cluster-signing-key-file=/opt/kubernetes/ssl/ca-key.pem \ --service-account-private-key-file=/opt/kubernetes/ssl/ca-key.pem \ --root-ca-file=/opt/kubernetes/ssl/ca.pem \ --leader-elect=true \ --v=2 \ --logtostderr=false \ --log-dir=/opt/kubernetes/log Restart=on-failure RestartSec=5 [Install] WantedBy=multi-user.target
启动Controller Manager
systemctl daemon-reload systemctl enable kube-controller-manager systemctl start kube-controller-manager
#查看状态 systemctl status kube-controller-manager [root@k8s-master ssl]# netstat -lntup|grep kube-controll tcp 0 0 127.0.0.1:10252 0.0.0.0:* LISTEN 27899/kube-controll
部署Kubernetes Scheduler
[root@k8s-master ssl]# vim /usr/lib/systemd/system/kube-scheduler.service [Unit] Description=Kubernetes Scheduler Documentation=https://github.com/GoogleCloudPlatform/kubernetes [Service] ExecStart=/opt/kubernetes/bin/kube-scheduler \ --address=127.0.0.1 \ --master=http://127.0.0.1:8080 \ --leader-elect=true \ --v=2 \ --logtostderr=false \ --log-dir=/opt/kubernetes/log Restart=on-failure RestartSec=5 [Install] WantedBy=multi-user.target
启动Kubernetes Scheduler
systemctl daemon-reload systemctl enable kube-scheduler systemctl start kube-scheduler #查看服务状态 systemctl status kube-scheduler [root@k8s-master ssl]# netstat -lntup|grep kube-schedule tcp 0 0 127.0.0.1:10251 0.0.0.0:* LISTEN 27955/kube-schedule
部署kubectl 命令行工具
kubectl是通过API Server来管理k8s集群的，kubectl和API Server之间通信也需要证书认证。kubectl 只在Master管理节点安装，下面来生成证书。
1.准备二进制命令包
[root@k8s-master ssl]# cd /usr/local/src/kubernetes/client/bin [root@k8s-master bin]# cp kubectl /opt/kubernetes/bin/
2.创建 admin 证书签名请求
[root@k8s-master bin]# cd /usr/local/src/ssl/ [root@k8s-master ssl]# vim admin-csr.json { "CN": "admin", "hosts": [], "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "ST": "BeiJing", "L": "BeiJing", "O": "system:masters", "OU": "System" } ] }
3.生成 admin 证书和私钥
[root@k8s-master ssl]# cfssl gencert -ca=/opt/kubernetes/ssl/ca.pem \ > -ca-key=/opt/kubernetes/ssl/ca-key.pem \ > -config=/opt/kubernetes/ssl/ca-config.json \ > -profile=kubernetes admin-csr.json | cfssljson -bare admin 2018/11/14 10:11:02 [INFO] generate received request 2018/11/14 10:11:02 [INFO] received CSR 2018/11/14 10:11:02 [INFO] generating key: rsa-2048 2018/11/14 10:11:02 [INFO] encoded CSR 2018/11/14 10:11:03 [INFO] signed certificate with serial number 725437256018406250545228596363344942073012526422 2018/11/14 10:11:03 [WARNING] This certificate lacks a "hosts" field. This makes it unsuitable for websites. For more information see the Baseline Requirements for the Issuance and Management of Publicly-Trusted Certificates, v.1.1.6, from the CA/Browser Forum (https://cabforum.org); specifically, section 10.2.3 ("Information Requirements"). #会生成4个文件 [root@k8s-master ssl]# ls -l admin* -rw-r--r-- 1 root root 1009 Nov 14 10:11 admin.csr -rw-r--r-- 1 root root 229 Nov 14 10:10 admin-csr.json -rw------- 1 root root 1679 Nov 14 10:11 admin-key.pem -rw-r--r-- 1 root root 1399 Nov 14 10:11 admin.pem
#移动到ssl证书目录
[root@k8s-master ssl]# mv admin*.pem /opt/kubernetes/ssl/
4.设置集群参数
[root@k8s-master ssl]# kubectl config set-cluster kubernetes \ > --certificate-authority=/opt/kubernetes/ssl/ca.pem \ > --embed-certs=true \ > --server=https://10.0.3.225:6443 Cluster "kubernetes" set.
5.设置客户端认证参数
[root@k8s-master ssl]# kubectl config set-credentials admin \ > --client-certificate=/opt/kubernetes/ssl/admin.pem \ > --embed-certs=true \ > --client-key=/opt/kubernetes/ssl/admin-key.pem User "admin" set.
6.设置上下文参数
[root@k8s-master ssl]# kubectl config set-context kubernetes \ > --cluster=kubernetes \ > --user=admin Context "kubernetes" created.
7.设置默认上下文
[root@k8s-master ssl]# kubectl config use-context kubernetes Switched to context "kubernetes".
#敲了一大堆命令，其实是在家目录.kube/ 生成一个config配置文件，kubectl和API Server通信就要使用到这个文件。 其他节点想要运行kubectl 就要把这个文件拷贝过去
root@k8s-master ~]# cat .kube/config
8.使用kubectl工具
[root@k8s-master ssl]# kubectl get cs NAME STATUS MESSAGE ERROR controller-manager Healthy ok scheduler Healthy ok etcd-1 Healthy {"health": "true"} etcd-0 Healthy {"health": "true"} etcd-2 Healthy {"health": "true"}