Kubernetes 0-1 二进制搭建K8S（三）部署Master

写在前面

记录和分享使用二进制搭建K8S集群的详细过程，由于操作比较冗长，大概会分四篇写完：

1. 机器准备
2. 部署etcd集群
3. 部署Master
4. 部署Node

我们已经知道在K8S的Master上存在着kube-apiserver、kube-controller-manager、kube-scheduler三大组件。本篇介绍在Master机器安装这些组件，除此之外，如果想在Master机器上操作集群，还需要安装kubectl工具。

安装kubectl

kubernetes的安装包里已经将kubectl包含进去了，部署很简单：

cd /root/kubernetes/resources/
tar -zxvf ./kubernetes-server-linux-amd64.tar.gz
cp kubernetes/server/bin/kubectl /usr/bin
kubectl api-versions

制作kubernetes证书

mkdir /root/kubernetes/resources/cert/kubernetes /etc/kubernetes/{ssl,bin} -p
cp kubernetes/server/bin/kube-apiserver kubernetes/server/bin/kube-controller-manager kubernetes/server/bin/kube-scheduler /etc/kubernetes/bin
cd /root/kubernetes/resources/cert/kubernetes

接下来都在Master机器上执行，编辑ca-config.json

vim ca-config.json

写入文件内容如下：

{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "kubernetes": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}

编辑ca-csr.json：

vim ca-csr.json

写入文件内容如下：

{
    "CN": "kubernetes",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Hunan",
            "ST": "Changsha",            
      	    "O": "kubernetes",
            "OU": "System"
        }
    ]
}

生成ca证书和密钥：

cfssl gencert -initca ca-csr.json | cfssljson -bare ca

制作kube-apiserver、kube-proxy、admin证书，编辑kube-apiserver-csr.json：

vim kube-apiserver-csr.json

写入文件内容如下：

{
    "CN": "kubernetes",
    "hosts": [
        "10.0.0.1",
        "127.0.0.1",
        "kubernetes",
        "kubernetes.default",
        "kubernetes.default.svc",
        "kubernetes.default.svc.cluster",
        "kubernetes.default.svc.cluster.local",
        "192.168.115.131",
        "192.168.115.132",
        "192.168.115.133"
        ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Hunan",
            "ST": "Changsha",
            "O": "kubernetes",
            "OU": "System"
        }
    ]
}

编辑kube-proxy-csr.json：

vim kube-proxy-csr.json

写入文件内容如下：

{
    "CN": "system:kube-proxy",
    "hosts": [],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Hunan",
            "ST": "Changsha",
            "O": "kubernetes",
            "OU": "System"
        }
    ]
}

编辑admin-csr.json：

vim admin-csr.json

写入文件内容如下：

{
    "CN": "admin",
    "hosts": [],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Hunan",
            "ST": "Changsha",
            "O": "system:masters",
            "OU": "System"
        }
    ]
}

生成证书和密钥

cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-apiserver-csr.json | cfssljson -bare kube-apiserver
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-proxy-csr.json | cfssljson -bare kube-proxy
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes admin-csr.json | cfssljson -bare admin
# 此时目录下生成的文件
ll
-rw-r--r--. 1 root root 1001 May 28 00:32 admin.csr
-rw-r--r--. 1 root root  282 May 28 00:32 admin-csr.json
-rw-------. 1 root root 1679 May 28 00:32 admin-key.pem
-rw-r--r--. 1 root root 1407 May 28 00:32 admin.pem
-rw-r--r--. 1 root root  294 May 28 00:30 ca-config.json
-rw-r--r--. 1 root root 1013 May 28 00:31 ca.csr
-rw-r--r--. 1 root root  284 May 28 00:30 ca-csr.json
-rw-------. 1 root root 1675 May 28 00:31 ca-key.pem
-rw-r--r--. 1 root root 1383 May 28 00:31 ca.pem
-rw-r--r--. 1 root root 1273 May 28 00:32 kube-apiserver.csr
-rw-r--r--. 1 root root  597 May 28 00:31 kube-apiserver-csr.json
-rw-------. 1 root root 1679 May 28 00:32 kube-apiserver-key.pem
-rw-r--r--. 1 root root 1655 May 28 00:32 kube-apiserver.pem
-rw-r--r--. 1 root root 1009 May 28 00:32 kube-proxy.csr
-rw-r--r--. 1 root root  287 May 28 00:31 kube-proxy-csr.json
-rw-------. 1 root root 1679 May 28 00:32 kube-proxy-key.pem
-rw-r--r--. 1 root root 1411 May 28 00:32 kube-proxy.pem

将kube-proxy证书拷贝到Node：

前提，需要在Node机器创建目录，以下命令在Node机器上执行：

mkdir /etc/kubernetes/ -p

然后再在Master机器执行拷贝操作。

cp ca.pem ca-key.pem kube-apiserver.pem kube-apiserver-key.pem kube-proxy.pem kube-proxy-key.pem /etc/kubernetes/ssl
scp -r /etc/kubernetes/ssl 192.168.115.132:/etc/kubernetes
scp -r /etc/kubernetes/ssl 192.168.115.133:/etc/kubernetes

创建TLSBootstrapping Token

cd /etc/kubernetes
head -c 16 /dev/urandom | od -An -t x | tr -d ‘ ‘
# 执行上一步会得到一个token，例如d5c5d767b64db39db132b433e9c45fbc，编辑文件token.csv时需要
vim token.csv

写入文件内容，替换生成的token

d5c5d767b64db39db132b433e9c45fbc,kubelet-bootstrap,10001,"system:node-bootstrapper"

安装kube-apiserver

准备kube-apiserver配置文件

vim apiserver

执行上行命令，写入文件内容如下：

KUBE_API_ARGS="--logtostderr=false --v=2 --log-dir=/var/log/kubernetes --etcd-servers=https://192.168.115.131:2379,https://192.168.115.132:2379,https://192.168.115.133:2379 --bind-address=192.168.115.131 --secure-port=6443 --advertise-address=192.168.115.131 --allow-privileged=true --service-cluster-ip-range=10.0.0.0/24 --enable-admission-plugins=NamespaceLifecycle,LimitRanger,ServiceAccount,ResourceQuota,NodeRestriction --authorization-mode=RBAC,Node --enable-bootstrap-token-auth=true --token-auth-file=/etc/kubernetes/token.csv --service-node-port-range=30000-32767 --kubelet-client-certificate=/etc/kubernetes/ssl/kube-apiserver.pem --kubelet-client-key=/etc/kubernetes/ssl/kube-apiserver-key.pem --tls-cert-file=/etc/kubernetes/ssl/kube-apiserver.pem  --tls-private-key-file=/etc/kubernetes/ssl/kube-apiserver-key.pem --client-ca-file=/etc/kubernetes/ssl/ca.pem --service-account-key-file=/etc/kubernetes/ssl/ca-key.pem --etcd-cafile=/etc/etcd/ssl/ca.pem --etcd-certfile=/etc/etcd/ssl/server.pem --etcd-keyfile=/etc/etcd/ssl/server-key.pem --audit-log-maxage=30 --audit-log-maxbackup=3 --audit-log-maxsize=100 --audit-log-path=/var/logs/kubernetes/k8s-audit.log"

准备kube-apiserver服务配置文件

vim /usr/lib/systemd/system/kube-apiserver.service

执行上行命令，写入文件内容如下：

[Unit]
Description=Kubernetes API Server
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=etcd.service
Wants=etcd.service

[Service]
Type=notify
EnvironmentFile=/etc/kubernetes/apiserver
ExecStart=/etc/kubernetes/bin/kube-apiserver $KUBE_API_ARGS
Restart=on-failure
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target

启动kube-apiserver:

systemctl daemon-reload
systemctl start kube-apiserver
systemctl enable kube-apiserver
systemctl status kube-apiserver

安装kube-controller-manager

准备kube-controller-manger配置文件

vim controller-manager

执行上行命令，写入文件内容如下：

KUBE_CONTROLLER_MANAGER_ARGS="--logtostderr=false --v=2 --log-dir=/var/log/kubernetes --leader-elect=true --master=127.0.0.1:8080 --bind-address=127.0.0.1 --allocate-node-cidrs=true --cluster-cidr=10.244.0.0/16 --service-cluster-ip-range=10.0.0.0/24 --cluster-signing-cert-file=/etc/kubernetes/ssl/ca.pem --cluster-signing-key-file=/etc/kubernetes/ssl/ca-key.pem  --root-ca-file=/etc/kubernetes/ssl/ca.pem --service-account-private-key-file=/etc/kubernetes/ssl/ca-key.pem --experimental-cluster-signing-duration=87600h0m0s"

准备kube-controller-manger服务配置文件

vim /usr/lib/systemd/system/kube-controller-manager.service

执行上行命令，写入文件内容如下：

[Unit]
Description=Kubernetes Controller Manager
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=kube-apiserver.service
Requires=kube-apiserver.service

[Service]
EnvironmentFile=/etc/kubernetes/controller-manager
ExecStart=/etc/kubernetes/bin/kube-controller-manager $KUBE_CONTROLLER_MANAGER_ARGS
Restart=on-failure
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target

启动kube-controller-manager:

systemctl daemon-reload
systemctl start kube-controller-manager
systemctl enable kube-controller-manager
systemctl status kube-controller-manager

安装kube-scheduler

准备kube-scheduler配置文件

vim scheduler

执行上行命令，写入文件内容如下：

KUBE_SCHEDULER_ARGS="--logtostderr=false --v=2 --log-dir=/var/log/kubernetes --master=127.0.0.1:8080 --leader-elect --bind-address=127.0.0.1"

准备kube-scheduler服务配置文件

vim /usr/lib/systemd/system/kube-scheduler.service

执行上行命令，写入文件内容如下：

[Unit]
Description=Kubernetes Scheduler
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=kube-apiserver.service
Requires=kube-apiserver.service

[Service]
EnvironmentFile=/etc/kubernetes/scheduler
ExecStart=/etc/kubernetes/bin/kube-scheduler $KUBE_SCHEDULER_ARGS
Restart=on-failure
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target

启动kube-scheduler:

systemctl daemon-reload
systemctl start kube-scheduler
systemctl enable kube-scheduler
systemctl status kube-scheduler

kubelet-bootstrap授权

kubectl create clusterrolebinding kubelet-bootstrap --clusterrole=system:node-bootstrapper --user=kubelet-bootstrap

查看Master状态

kubectl get cs

如果Master部署成功，应该输出：

NAME                 STATUS    MESSAGE             ERROR
scheduler            Healthy   ok                  
controller-manager   Healthy   ok                  
etcd-2               Healthy   {"health":"true"}   
etcd-1               Healthy   {"health":"true"}   
etcd-0               Healthy   {"health":"true"}

apiserver授权kubelet

准备apiserver-to-kubelet-rbac.yaml文件

cd /root/kubernetes/resources
vim apiserver-to-kubelet-rbac.yaml

执行上行命令，写入文件内容如下：

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  annotations:
    rbac.authorization.kubernetes.io/autoupdate: "true"
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
  name: system:kube-apiserver-to-kubelet
rules:
  - apiGroups:
      - ""
    resources:
      - nodes/proxy
      - nodes/stats
      - nodes/log
      - nodes/spec
      - nodes/metrics
      - pods/log
    verbs:
      - "*"
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: system:kube-apiserver
  namespace: ""
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:kube-apiserver-to-kubelet
subjects:
  - apiGroup: rbac.authorization.k8s.io
    kind: User
    name: kubernetes
    
# This role allows full access to the kubelet API
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: kubelet-api-admin
  labels:
    addonmanager.kubernetes.io/mode: Reconcile
rules:
- apiGroups:
  - ""
  resources:
  - nodes/proxy
  - nodes/log
  - nodes/stats
  - nodes/metrics
  - nodes/spec
  verbs:
  - "*"
# This binding gives the kube-apiserver user full access to the kubelet API
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: kube-apiserver-kubelet-api-admin
  labels:
    addonmanager.kubernetes.io/mode: Reconcile
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: kubelet-api-admin
subjects:
- apiGroup: rbac.authorization.k8s.io
  kind: User
  name: kube-apiserver

执行以下命令：

kubectl apply -f apiserver-to-kubelet-rbac.yaml

第三段落部署Master顺利结束。