二进制安装K8S集群-上

---

一、基本环境配置

1.1 集群规划

主机	IP地址	说明	需手动安装组件
k8s-master01	192.168.1.10	Master01节点	etcd、kube-apiserver、controller manager, scheduler、kube-proxy、kubelet、keepalived+haproxy、kubectl
k8s-master02	192.168.1.11	Master02节点	etcd，kube-apiserver，controller manager, scheduler，kube-proxy，kubelet，keepalived+haproxy，
k8s-master03	192.168.1.12	Master03节点	etcd、kube-apiserver、controller manager, scheduler、kube-proxy、kubelet
k8s-node01	192.168.1.101	Node01节点	kube-proxy，kubelet

1.2 网段及版本信息

K8S与Docker等的版本依赖关系

配置信息	说明
系统版本	CentOS7.9
内核	内核-ml-4.19.12
K8S版本	1.23.*
Docker 版本	20.10.*
etcd版本	3.5.*
主机网段	192.168.1.0/24
Pod网段	172.16.0.0/12 10.244.0.0/12
Service网段	10.0.0.0/16

kubeadm安装方式各组件配置

组件	运行方式	配置所在位置	生效方式
kubelet	主机	/etc/sysconfig/kubelet；/var/lib/kubelet/config.yaml	重新启动kubelet进程
etcd	容器	/etc/kubernetes/manifests	等待自动刷新pod，或重启kubelet
kube-apiserver	容器	/etc/kubernetes/manifests	同上
kube-scheduler	容器	/etc/kubernetes/manifests	同上
kube-controller-manager	容器	/etc/kubernetes/manifests	同上
kube-proxy	容器	configmap	修改configmap，重新patch

1.3 服务器优化及升级

服务器优化及内核升级

1.4 安装Runtime

Runtime安装

1.5 kube-apiserver 高可用实现

kube-apiserver高可用实现

1.6 K8S&ETCD安装包下载

Kubernetes
下载kubernetes安装包，选择当前最新的稳定版（v1.23.4），官方发布地址：

https://github.com/kubernetes/kubernetes/tree/master/CHANGELOG
[root@k8s-master01  ~]# wget https://dl.k8s.io/v1.23.4/kubernetes-server-linux-amd64.tar.gz  # server版包括了所有组件

etcd
etcd是CoreOS团队于2013年6月发起的开源项目，它的目标是构建一个高可用的分布式键值(key-value)数据库。etcd内部采用raft协议作为一致性算法，etcd基于Go语言实现。

下载etcd安装包，选择v3.5.0，官方发布地址：

https://github.com/etcd-io/etcd/releases
[root@k8s-master01  ~]# wget https://github.com/etcd-io/etcd/releases/download/v3.5.0/etcd-v3.5.0-linux-amd64.tar.gz

分别解压

[root@k8s-master01  ~]# tar -xf kubernetes-server-linux-amd64.tar.gz  --strip-components=3 -C /usr/local/bin kubernetes/server/bin/kube{let,ctl,-apiserver,-controller-manager,-scheduler,-proxy}   # 解压kubernetes安装文件
[root@k8s-master01  ~]# tar -zxvf etcd-v3.5.0-linux-amd64.tar.gz --strip-components=1 -C /usr/local/bin etcd-v3.5.0-linux-amd64/etcd{,ctl}   # 解压etcd安装文件

测试

[root@k8s-master01 /]# kubelet --version
Kubernetes v1.23.4
[root@k8s-master01 /]# etcdctl version
etcdctl version: 3.5.0
API version: 3.5

1.7 将组件发送到其他节点

[root@k8s-master01  ~]# MasterNodes='k8s-master02 k8s-master03'
[root@k8s-master01  ~]# WorkNodes='k8s-node01'
[root@k8s-master01  ~]# for NODE in $MasterNodes; do echo $NODE; scp /usr/local/bin/kube{let,ctl,-apiserver,-controller-manager,-scheduler,-proxy} $NODE:/usr/local/bin/; scp /usr/local/bin/etcd* $NODE:/usr/local/bin/; done
[root@k8s-master01  ~]# for NODE in $WorkNodes; do scp /usr/local/bin/kube{let,-proxy} $NODE:/usr/local/bin/; done

所有节点创建目录

[root@k8s-master01 /]# mkdir /opt/cni
[root@k8s-master01 /]# mkdir /opt/cni/bin

二、制作证书

Kubernetes 系统各组件需要使用 TLS 证书对通信进行加密。

2.1 下载生成证书工具CFSSL

语言是Flare的PKICloudGo，CF包含一个使用SSL等验证工具和SSL证书的工具和一个用于签名，捆绑TLSHTTP服务，HTTP服务，Kubernetes等组件的中会。在编写kubernetes等组件的中会。大量接触到证书的生成和使用。

[root@k8s-master01  ~]# wget "https://github.com/cloudflare/cfssl/releases/download/v1.6.1/cfssl_1.6.1_linux_amd64" -O /usr/local/bin/cfssl
[root@k8s-master01  ~]# wget "https://github.com/cloudflare/cfssl/releases/download/v1.6.1/cfssljson_1.6.1_linux_amd64" -O /usr/local/bin/cfssljson
 #自行上传
[root@k8s-master01  ~]# mv cfssl_1.6.1_linux_amd64  /usr/local/bin/cfssl   
[root@k8s-master01  ~]# mv cfssljson_1.6.1_linux_amd64 /usr/local/bin/cfssljson

[root@k8s-master01  ~]# chmod +x /usr/local/bin/cfssl /usr/local/bin/cfssljson

2.2 ETCD证书

所有master节点创建etcd证书目录

[root@k8s-master01  ~]# mkdir -p /etc/etcd/ssl

所有节点创建kubernetes相关目录，证书放在/etc/kubernetes/pki下

[root@k8s-master01  ~]# mkdir -p /etc/kubernetes/pki

创建etcd-ca-csr.json，修改年限为100年

CN（Common Name)：etcd/kube-apiserver从证书中提取该字段作为请求的用户名 (User Name)；浏览器使用该字段验证网站是否合法，一般写的是域名。
O（Organization）：etcd/kube-apiserver 从证书中提取该字段作为请求用户所属的组 (Group)；

这两个参数在后面的kubernetes启用RBAC模式中很重要，因为需要设置kubelet、admin等角色权限

C（Country）: 国家
ST（State）: 州，省
L（Locality）：地区，城市
O: Organization Name，组织名称，公司名称
OU（Organization Unit Name）: 组织单位名称，公司部门

[root@k8s-master01  ~]# cat > etcd-ca-csr.json << EOF
{
  "CN": "etcd",
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "Beijing",
      "L": "Beijing",
      "O": "etcd",
      "OU": "Etcd Security"
    }
  ],
  "ca": {
    "expiry": "876000h"
  }
}
EOF

生成etcd的CA认证中心

[root@k8s-master01  ~]# cfssl gencert -initca etcd-ca-csr.json | cfssljson -bare /etc/etcd/ssl/etcd-ca  # 初始化创建CA认证中心，将会生成 ca-key.pem（私钥）  ca.pem（公钥）
# etcd-ca.csr      # 根证书申请文件
# etcd-ca-key.pem  # 根证书私钥
# etcd-ca.pem      # 根证书公钥
[root@k8s-master01 ssl]# openssl x509 -in etcd-ca.pem -noout -text |grep ' Not '   # 查看证书时间

创建 ca-config.json

知识点：
ca-config.json：可以定义多个 profiles，分别指定不同的过期时间、使用场景等参数；后续在签名证书时使用某个 profile；此实例只有一个kubernetes模板。
signing：表示该证书可用于签名其它证书；生成的 ca.pem 证书中 CA=TRUE；
server auth：表示client可以用该CA对server提供的证书进行验证；
client auth：表示server可以用该CA对client提供的证书进行验证；

[root@k8s-master01  ~]# cat > ca-config.json << EOF
{
  "signing": {
    "default": {
      "expiry": "876000h"
    },
    "profiles": {
      "kubernetes": {
        "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ],
        "expiry": "876000h"
      }
    }
  }
}
EOF

etcd-csr.json

[root@k8s-master01  ~]# cat > etcd-csr.json << EOF
{
  "CN": "etcd",
  "hosts": [
    "127.0.0.1",
    "k8s-master01",
    "k8s-master02",
    "k8s-master03",
    "192.168.1.10",
    "192.168.1.11",
    "192.168.1.12"
  ],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "Beijing",
      "L": "Beijing",
      "O": "etcd",
      "OU": "Etcd Security"
    }
  ]
}
EOF

签发

[root@k8s-master01  ~]# cfssl gencert \
   -ca=/etc/etcd/ssl/etcd-ca.pem \
   -ca-key=/etc/etcd/ssl/etcd-ca-key.pem \
   -config=ca-config.json \
   -profile=kubernetes \
   etcd-csr.json | cfssljson -bare /etc/etcd/ssl/etcd   
# 初始化CA认证中心
etcd-ca.csr
etcd-ca-key.pem
etcd-ca.pem
# 签发
etcd.csr
etcd-key.pem
etcd.pem

证书复制到其他节点

[root@k8s-master01  ~]# MasterNodes='k8s-master02 k8s-master03'
[root@k8s-master01  ~]# for NODE in $MasterNodes; do
     ssh $NODE "mkdir -p /etc/etcd/ssl"
     for FILE in etcd-ca-key.pem  etcd-ca.pem  etcd-key.pem  etcd.pem; do
       scp /etc/etcd/ssl/${FILE} $NODE:/etc/etcd/ssl/${FILE}
     done
 done

2.3 apiserver 证书

创建k8s证书目录

[root@k8s-master01  ~]# mkdir -p /etc/kubernetes/pki/

创建ca-csr.json，修改年限为100年

[root@k8s-master01  ~]# cat > ca-csr.json << EOF
{
  "CN": "kubernetes",
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "Beijing",
      "L": "Beijing",
      "O": "Kubernetes",
      "OU": "Kubernetes-manual"
    }
  ],
  "ca": {
    "expiry": "876000h"
  }
}
EOF

生成k8s的CA认证中心

# 创建k8s的CA认证中心，将会生成 ca-key.pem（私钥）  ca.pem（公钥）
[root@k8s-master01  ~]# cfssl gencert -initca ca-csr.json | cfssljson -bare /etc/kubernetes/pki/ca
# etcd-ca.csr      # 根证书申请文件
# etcd-ca-key.pem  # 根证书私钥
# etcd-ca.pem      # 根证书公钥

创建 ca-config.json

知识点：
ca-config.json：可以定义多个 profiles，分别指定不同的过期时间、使用场景等参数；后续在签名证书时使用某个 profile；此实例只有一个kubernetes模板。

signing：表示该证书可用于签名其它证书；生成的 ca.pem 证书中 CA=TRUE；
server auth：表示client可以用该CA对server提供的证书进行验证；
client auth：表示server可以用该CA对client提供的证书进行验证；

[root@k8s-master01  ~]# cat  > ca-config.json << EOF
{
  "signing": {
    "default": {
      "expiry": "876000h"
    },
    "profiles": {
      "kubernetes": {
        "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ],
        "expiry": "876000h"
      }
    }
  }
}
EOF

apiserver-csr.json

service网段第一个IP
所有masterIP
负载均衡IP

[root@k8s-master01  ~]# cat > apiserver-csr.json << EOF
{
  "CN": "kube-apiserver",
  "hosts": [
    "10.0.0.1",
    "192.168.1.10",
    "127.0.0.1",
    "kubernetes",
    "kubernetes.default",
    "kubernetes.default.svc",
    "kubernetes.default.svc.cluster",
    "kubernetes.default.svc.cluster.local"
    "192.168.1.11",
    "192.168.1.12"
  ],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "Beijing",
      "L": "Beijing",
      "O": "Kubernetes",
      "OU": "Kubernetes-manual"
    }
  ]
}
EOF

签发

[root@k8s-master01  ~]# cfssl gencert \
    -ca=/etc/kubernetes/pki/ca.pem \
    -ca-key=/etc/kubernetes/pki/ca-key.pem \
    -config=ca-config.json \
    -profile=kubernetes \
    apiserver-csr.json | cfssljson -bare /etc/kubernetes/pki/apiserver

2.4 apiserver聚合证书

front-proxy-ca-csr.json

[root@k8s-master01  ~]# cat > front-proxy-ca-csr.json << EOF
{
  "CN": "kubernetes",
  "key": {
     "algo": "rsa",
     "size": 2048
  },
  "ca": {
    "expiry": "876000h"
  }
}
EOF

创建apiserver聚合证书的CA认证中心

[root@k8s-master01  ~]# cfssl gencert -initca front-proxy-ca-csr.json | cfssljson -bare /etc/kubernetes/pki/front-proxy-ca 

[root@k8s-master01  ~]# cat > front-proxy-client-csr.json << EOF
{
  "CN": "front-proxy-client",
  "key": {
     "algo": "rsa",
     "size": 2048
  }
}
EOF

签发

[root@k8s-master01  ~]# cfssl gencert \
    -ca=/etc/kubernetes/pki/front-proxy-ca.pem \
    -ca-key=/etc/kubernetes/pki/front-proxy-ca-key.pem \
    -config=ca-config.json \
    -profile=kubernetes \
    front-proxy-client-csr.json | cfssljson -bare /etc/kubernetes/pki/front-proxy-client

2.5 controller-manage证书

[root@k8s-master01  ~]# cat > manager-csr.json << EOF
{
  "CN": "system:kube-controller-manager",
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "Beijing",
      "L": "Beijing",
      "O": "system:kube-controller-manager",
      "OU": "Kubernetes-manual"
    }
  ]
}
EOF

签发

[root@k8s-master01  ~]# cfssl gencert \
   -ca=/etc/kubernetes/pki/ca.pem \
   -ca-key=/etc/kubernetes/pki/ca-key.pem \
   -config=ca-config.json \
   -profile=kubernetes \
   manager-csr.json | cfssljson -bare /etc/kubernetes/pki/controller-manager

2.6 配置controller-manager.kubeconfig

[root@k8s-master01  ~]# kubectl config set-cluster kubernetes \
     --certificate-authority=/etc/kubernetes/pki/ca.pem \
     --embed-certs=true \
     --server=https://192.168.1.10:8443 \
     --kubeconfig=/etc/kubernetes/controller-manager.kubeconfig

设置一个环境项，一个上下文

[root@k8s-master01  ~]# kubectl config set-context system:kube-controller-manager@kubernetes \
    --cluster=kubernetes \
    --user=system:kube-controller-manager \
    --kubeconfig=/etc/kubernetes/controller-manager.kubeconfig

set-credentials 设置一个用户项

[root@k8s-master01  ~]# kubectl config set-credentials system:kube-controller-manager \
     --client-certificate=/etc/kubernetes/pki/controller-manager.pem \
     --client-key=/etc/kubernetes/pki/controller-manager-key.pem \
     --embed-certs=true \
     --kubeconfig=/etc/kubernetes/controller-manager.kubeconfig

使用某个环境当做默认环境

[root@k8s-master01  ~]# kubectl config use-context system:kube-controller-manager@kubernetes \
     --kubeconfig=/etc/kubernetes/controller-manager.kubeconfig

2.7 scheduler证书

[root@k8s-master01  ~]# cat > scheduler-csr.json<< EOF
{
  "CN": "system:kube-scheduler",
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "Beijing",
      "L": "Beijing",
      "O": "system:kube-scheduler",
      "OU": "Kubernetes-manual"
    }
  ]
}
EOF

签发

[root@k8s-master01  ~]# cfssl gencert \
   -ca=/etc/kubernetes/pki/ca.pem \
   -ca-key=/etc/kubernetes/pki/ca-key.pem \
   -config=ca-config.json \
   -profile=kubernetes \
   scheduler-csr.json | cfssljson -bare /etc/kubernetes/pki/scheduler

配置scheduler.kubeconfig

[root@k8s-master01  ~]# kubectl config set-cluster kubernetes \
     --certificate-authority=/etc/kubernetes/pki/ca.pem \
     --embed-certs=true \
     --server=https://192.168.1.10:8443 \
     --kubeconfig=/etc/kubernetes/scheduler.kubeconfig

[root@k8s-master01  ~]# kubectl config set-credentials system:kube-scheduler \
     --client-certificate=/etc/kubernetes/pki/scheduler.pem \
     --client-key=/etc/kubernetes/pki/scheduler-key.pem \
     --embed-certs=true \
     --kubeconfig=/etc/kubernetes/scheduler.kubeconfig

[root@k8s-master01  ~]# kubectl config set-context system:kube-scheduler@kubernetes \
     --cluster=kubernetes \
     --user=system:kube-scheduler \
     --kubeconfig=/etc/kubernetes/scheduler.kubeconfig

[root@k8s-master01  ~]# kubectl config use-context system:kube-scheduler@kubernetes \
     --kubeconfig=/etc/kubernetes/scheduler.kubeconfig

2.8 admin证书

admin-csr.json

[root@k8s-master01  ~]# cat > admin-csr.json << EOF
{
  "CN": "admin",
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "Beijing",
      "L": "Beijing",
      "O": "system:masters",
      "OU": "Kubernetes-manual"
    }
  ]
}
EOF

签发

[root@k8s-master01  ~]# cfssl gencert \
   -ca=/etc/kubernetes/pki/ca.pem \
   -ca-key=/etc/kubernetes/pki/ca-key.pem \
   -config=ca-config.json \
   -profile=kubernetes \
   admin-csr.json | cfssljson -bare /etc/kubernetes/pki/admin

配置

[root@k8s-master01  ~]# kubectl config set-cluster kubernetes \
    --certificate-authority=/etc/kubernetes/pki/ca.pem \
    --embed-certs=true \
    --server=https://192.168.1.10:8443 \
    --kubeconfig=/etc/kubernetes/admin.kubeconfig

[root@k8s-master01  ~]# kubectl config set-credentials kubernetes-admin \
    --client-certificate=/etc/kubernetes/pki/admin.pem \
    --client-key=/etc/kubernetes/pki/admin-key.pem \
    --embed-certs=true \
    --kubeconfig=/etc/kubernetes/admin.kubeconfig

[root@k8s-master01  ~]# kubectl config set-context kubernetes-admin@kubernetes \
    --cluster=kubernetes \
    --user=kubernetes-admin \
    --kubeconfig=/etc/kubernetes/admin.kubeconfig

[root@k8s-master01  ~]# kubectl config use-context kubernetes-admin@kubernetes \
    --kubeconfig=/etc/kubernetes/admin.kubeconfig

2.9 ServiceAccount Key

[root@k8s-master01  ~]# openssl genrsa -out /etc/kubernetes/pki/sa.key 2048
[root@k8s-master01  ~]# openssl rsa -in /etc/kubernetes/pki/sa.key -pubout -out /etc/kubernetes/pki/sa.pub

2.10 发送证书至其他节点

[root@k8s-master01  ~]# for NODE in k8s-master02 k8s-master03; do 
  for FILE in $(ls /etc/kubernetes/pki | grep -v etcd); do 
    scp /etc/kubernetes/pki/${FILE} $NODE:/etc/kubernetes/pki/${FILE};
  done; 
  for FILE in admin.kubeconfig controller-manager.kubeconfig scheduler.kubeconfig; do 
    scp /etc/kubernetes/${FILE} $NODE:/etc/kubernetes/${FILE};
  done;
done

查看证书数量

[root@k8s-master01  ~]# ls /etc/kubernetes/pki/ |wc -l

三、Kubernetes系统组件配置

3.1 ETCD集群配置

master01

[root@k8s-master01  ~]# vim /etc/etcd/etcd.config.yml
name: 'k8s-master01'
data-dir: /var/lib/etcd
wal-dir: /var/lib/etcd/wal
snapshot-count: 5000
heartbeat-interval: 100
election-timeout: 1000
quota-backend-bytes: 0
listen-peer-urls: 'https://192.168.1.10:2380'
listen-client-urls: 'https://192.168.1.10:2379,http://127.0.0.1:2379'
max-snapshots: 3
max-wals: 5
cors:
initial-advertise-peer-urls: 'https://192.168.1.10:2380'
advertise-client-urls: 'https://192.168.1.10:2379'
discovery:
discovery-fallback: 'proxy'
discovery-proxy:
discovery-srv:
initial-cluster: 'k8s-master01=https://192.168.1.10:2380,k8s-master02=https://192.168.1.11:2380,k8s-master03=https://192.168.1.12:2380'
initial-cluster-token: 'etcd-k8s-cluster'
initial-cluster-state: 'new'
strict-reconfig-check: false
enable-v2: true
enable-pprof: true
proxy: 'off'
proxy-failure-wait: 5000
proxy-refresh-interval: 30000
proxy-dial-timeout: 1000
proxy-write-timeout: 5000
proxy-read-timeout: 0
client-transport-security:
  cert-file: '/etc/kubernetes/pki/etcd/etcd.pem'
  key-file: '/etc/kubernetes/pki/etcd/etcd-key.pem'
  client-cert-auth: true
  trusted-ca-file: '/etc/kubernetes/pki/etcd/etcd-ca.pem'
  auto-tls: true
peer-transport-security:
  cert-file: '/etc/kubernetes/pki/etcd/etcd.pem'
  key-file: '/etc/kubernetes/pki/etcd/etcd-key.pem'
  peer-client-cert-auth: true
  trusted-ca-file: '/etc/kubernetes/pki/etcd/etcd-ca.pem'
  auto-tls: true
debug: false
log-package-levels:
log-outputs: [default]
force-new-cluster: false

其它master节点注意修改名称和IP即可

创建etcd service并启动

[root@k8s-master01  ~]# cat > /usr/lib/systemd/system/etcd.service << EOF
[Unit]
Description=Etcd Service
Documentation=https://coreos.com/etcd/docs/latest/
After=network.target

[Service]
Type=notify
ExecStart=/usr/local/bin/etcd --config-file=/etc/etcd/etcd.config.yml
Restart=on-failure
RestartSec=10
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
Alias=etcd3.service
EOF

所有master节点创建etcd证书目录

[root@k8s-master01  ~]# mkdir -p /etc/kubernetes/pki/etcd
[root@k8s-master01  ~]# ln -s /etc/etcd/ssl/* /etc/kubernetes/pki/etcd/
[root@k8s-master01  ~]# systemctl daemon-reload
[root@k8s-master01  ~]# systemctl enable --now etcd

查看ETCD状态

[root@k8s-master01  ~]# export ETCDCTL_API=3
[root@k8s-master01 ~]# etcdctl --endpoints="192.168.1.10:2379,192.168.1.11:2379,192.168.1.12:2379" --cacert=/etc/kubernetes/pki/etcd/etcd-ca.pem --cert=/etc/kubernetes/pki/etcd/etcd.pem --key=/etc/kubernetes/pki/etcd/etcd-key.pem  endpoint status --write-out=table
+----------+----+---------+---------+-----------+------------+-----------+------------+--------------------+--------+
| ENDPOINT | ID | VERSION | DB SIZE | IS LEADER | IS LEARNER | RAFT TERM | RAFT INDEX | RAFT APPLIED INDEX | ERRORS |
+----------+----+---------+---------+-----------+------------+-----------+------------+--------------------+--------+
| 192.168.1.10:2379 | d3bd0760893752a8 | 3.5.0 | 20 kB | true  | false |         2 |        8 |      8 |        
| 192.168.1.11:2379 | ace8d5b0766b3d92 | 3.5.0 | 20 kB | false | false |         2 |        8 |      8 |     
| 192.168.1.12:2379 |  ac7e57d44f030e8 | 3.5.0 | 20 kB | false | false |         2 |        8 |      8 |
+----------+----+---------+---------+-----------+------------+-----------+------------+--------------------+--------+