文章目录

《部署一套完整的企业级K8s集群》

v1.20，二进制方式

作者信息李振良（阿良），微信：k8init
DevOps实战学院http://www.aliangedu.cn
说明该文档有导航窗格，方便阅读，如果左侧没有显示，请检查word是否启用。转载请注明作者，拒绝不道德行为！
一键部署脚本https://github.com/lizhenliang/ansible-install-k8s
最后更新时间2021-04-06

一、前置知识点

1.1 生产环境部署K8s集群的两种方式

  • kubeadm
    Kubeadm是一个K8s部署工具，提供kubeadm init和kubeadm join，用于快速部署Kubernetes集群。
  • 二进制包
    从github下载发行版的二进制包，手动部署每个组件，组成Kubernetes集群。
  • 小结：Kubeadm降低部署门槛，但屏蔽了很多细节，遇到问题很难排查。如果想更容易可控，推荐使用二进制包部署Kubernetes集群，虽然手动部署麻烦点，期间可以学习很多工作原理，也利于后期维护。

1.2 准备环境

  • 服务器要求：
    • 建议最小硬件配置：2核CPU、2G内存、30G硬盘
    • 服务器最好可以访问外网，会有从网上拉取镜像需求，如果服务器不能上网，需要提前下载对应镜像并导入节点
      软件环境：
软件版本
操作系统CentOS7.x_x64 （mini）
容器引擎Docker CE 19
KubernetesKubernetes v1.20

服务器整体规划：

角色IP组件
k8s-master1
|
192.168.100.61
|kube-apiserver，kube-controller-manager，kube-scheduler，kubelet，kube-proxy，docker，etcd，nginx，keepalived k8s-master2 |192.168.100.64 |kube-apiserver，kube-controller-manager，kube-scheduler，kubelet，kube-proxy，docker，nginx，keepalived k8s-node1 |192.168.100.62 |kubelet，kube-proxy，docker，etcd k8s-node2 |192.168.100.63 |kubelet，kube-proxy，docker，etcd 负载均衡器IP |192.168.100.65 (VIP) |

须知：考虑到有些朋友电脑配置较低，一次性开四台机器会跑不动，所以搭建这套K8s高可用集群分两部分实施，先部署一套单Master架构（3台），再扩容为多Master架构（4台或6台），顺便再熟悉下Master扩容流程。
单Master架构图：
在这里插入图片描述

单Master服务器规划：

角色IP组件
k8s-master192.168.100.61kube-apiserver，kube-controller-manager，kube-scheduler，kubelet，kube-proxy，docker，etcd，（3g内存）
k8s-node1192.168.100.62kubelet，kube-proxy，docker，etcd
k8s-node2192.168.100.63kubelet，kube-proxy，docker，etcd

1.3 操作系统初始化配置

# 关闭防火墙 
systemctl stop firewalld && systemctl disable firewalld 
 
# 关闭selinux 
sed -i 's/enforcing/disabled/' /etc/selinux/config  # 永久 
setenforce 0  # 临时 
 
# 关闭swap 
swapoff -a  # 临时 
sed -ri 's/.*swap.*/#&/' /etc/fstab    # 永久 
 
# 根据规划设置主机名 
hostnamectl set-hostname <hostname> 
 
# 在master添加hosts 
cat >> /etc/hosts << EOF 
192.168.100.61 k8s-master1 
192.168.100.62 k8s-node1 
192.168.100.63 k8s-node2 
192.168.100.64 k8s-master2 
EOF
 
# 将桥接的IPv4流量传递到iptables的链 
cat > /etc/sysctl.d/k8s.conf << EOF 
net.bridge.bridge-nf-call-ip6tables = 1 
net.bridge.bridge-nf-call-iptables = 1 
EOF
sysctl --system  # 生效 
 
# 时间同步 
yum install ntpdate -y && ntpdate time.windows.com

二、部署Etcd集群

Etcd 是一个分布式键值存储系统，Kubernetes使用Etcd进行数据存储，所以先准备一个Etcd数据库，为解决Etcd单点故障，应采用集群方式部署，这里使用3台组建集群，可容忍1台机器故障，当然，你也可以使用5台组建集群，可容忍2台机器故障。

节点名称IP
etcd-1192.168.100.61
etcd-2192.168.100.62
etcd-3192.168.100.63

注：为了节省机器，这里与K8s节点机器复用。也可以独立于k8s集群之外部署，只要apiserver能连接到就行。

2.1 准备cfssl证书生成工具

cfssl是一个开源的证书管理工具，使用json文件生成证书，相比openssl更方便使用。
找任意一台服务器操作，这里用Master节点。

wget https://pkg.cfssl.org/R1.2/cfssl_linux-amd64
wget https://pkg.cfssl.org/R1.2/cfssljson_linux-amd64
wget https://pkg.cfssl.org/R1.2/cfssl-certinfo_linux-amd64
chmod +x cfssl_linux-amd64 cfssljson_linux-amd64 cfssl-certinfo_linux-amd64
mv cfssl_linux-amd64 /usr/local/bin/cfssl
mv cfssljson_linux-amd64 /usr/local/bin/cfssljson
mv cfssl-certinfo_linux-amd64 /usr/local/bin/cfssl-certinfo

2.2 生成Etcd证书

1. 自签证书颁发机构（CA）

创建工作目录：

mkdir -p ~/TLS/{etcd,k8s}

cd ~/TLS/etcd

自签CA：

cat > ca-config.json << EOF
{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "www": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}
EOF

cat > ca-csr.json << EOF
{
    "CN": "etcd CA",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing"
        }
    ]
}
EOF

生成证书：

[root@k8s-master1 etcd]# cfssl gencert -initca ca-csr.json | cfssljson -bare ca -
2021/12/12 04:18:51 [INFO] generating a new CA key and certificate from CSR
2021/12/12 04:18:51 [INFO] generate received request
2021/12/12 04:18:51 [INFO] received CSR
2021/12/12 04:18:51 [INFO] generating key: rsa-2048
2021/12/12 04:18:51 [INFO] encoded CSR
2021/12/12 04:18:51 [INFO] signed certificate with serial number 366484398928188099463200196143389891567502667552
[root@k8s-master1 etcd]# ll
total 20
-rw-r--r--. 1 root root  287 Dec 12 04:01 ca-config.json
-rw-r--r--. 1 root root  956 Dec 12 04:18 ca.csr
-rw-r--r--. 1 root root  209 Dec 12 04:02 ca-csr.json
-rw-------. 1 root root 1675 Dec 12 04:18 ca-key.pem
-rw-r--r--. 1 root root 1265 Dec 12 04:18 ca.pem

在这里插入图片描述
会生成ca.pem和ca-key.pem文件。

2. 使用自签CA签发Etcd HTTPS证书

创建证书申请文件：

cat > server-csr.json << EOF
{
    "CN": "etcd",
    "hosts": [
    "192.168.100.61",
    "192.168.100.62",
    "192.168.100.63",
    "192.168.100.64",
    "192.168.100.65",
    "192.168.100.66",
    "192.168.100.67"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "BeiJing",
            "ST": "BeiJing"
        }
    ]
}
EOF

注：上述文件hosts字段中IP为所有etcd节点的集群内部通信IP，一个都不能少！为了方便后期扩容可以多写几个预留的IP。

生成证书：

cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=www server-csr.json | cfssljson -bare server

会生成server.pem和server-key.pem文件。
在这里插入图片描述

2.3 从Github下载二进制文件

下载地址：https://github.com/etcd-io/etcd/releases/download/v3.4.9/etcd-v3.4.9-linux-amd64.tar.gz

[root@k8s-master1 ~]# wget https://github.com/etcd-io/etcd/releases/download/v3.4.9/etcd-v3.4.9-linux-amd64.tar.gz
--2021-12-12 04:25:12--  https://github.com/etcd-io/etcd/releases/download/v3.4.9/etcd-v3.4.9-linux-amd64.tar.gz
Resolving github.com (github.com)... 20.205.243.166
Connecting to github.com (github.com)|20.205.243.166|:443... connected.
HTTP request sent, awaiting response... 302 Found
Location: https://objects.githubusercontent.com/github-production-release-asset-2e65be/11225014/7548e300-9b63-11ea-958d-569643dcaaea?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWNJYAX4CSVEH53A%2F20211212%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20211212T122524Z&X-Amz-Expires=300&X-Amz-Signature=b76af2df7138f3044f8f9ca1ecace49a034b1c59fed54d4f4fe3a50cd1b3c470&X-Amz-SignedHeaders=host&actor_id=0&key_id=0&repo_id=11225014&response-content-disposition=attachment%3B%20filename%3Detcd-v3.4.9-linux-amd64.tar.gz&response-content-type=application%2Foctet-stream [following]
--2021-12-12 04:25:24--  https://objects.githubusercontent.com/github-production-release-asset-2e65be/11225014/7548e300-9b63-11ea-958d-569643dcaaea?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWNJYAX4CSVEH53A%2F20211212%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20211212T122524Z&X-Amz-Expires=300&X-Amz-Signature=b76af2df7138f3044f8f9ca1ecace49a034b1c59fed54d4f4fe3a50cd1b3c470&X-Amz-SignedHeaders=host&actor_id=0&key_id=0&repo_id=11225014&response-content-disposition=attachment%3B%20filename%3Detcd-v3.4.9-linux-amd64.tar.gz&response-content-type=application%2Foctet-stream
Resolving objects.githubusercontent.com (objects.githubusercontent.com)... 185.199.109.133, 185.199.110.133, 185.199.108.133, ...
Connecting to objects.githubusercontent.com (objects.githubusercontent.com)|185.199.109.133|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 17364053 (17M) [application/octet-stream]
Saving to: ‘etcd-v3.4.9-linux-amd64.tar.gz’

100%[==============================================================================================================================================>] 17,364,053   132KB/s   in 3m 42s

2021-12-12 04:29:08 (76.3 KB/s) - ‘etcd-v3.4.9-linux-amd64.tar.gz’ saved [17364053/17364053]

[root@k8s-master1 ~]#
[root@k8s-master1 ~]# scp etcd-v3.4.9-linux-amd64.tar.gz root@192.168.100.62:/root
root@192.168.100.62's password:
etcd-v3.4.9-linux-amd64.tar.gz    100%   17MB  65.9MB/s   00:00
[root@k8s-master1 ~]# scp etcd-v3.4.9-linux-amd64.tar.gz root@192.168.100.63:/root
root@192.168.100.63's password:
etcd-v3.4.9-linux-amd64.tar.gz    100%   17MB  65.4MB/s   00:00
[root@k8s-master1 ~]#

在这里插入图片描述

2.4 部署Etcd集群

以下在节点1上操作，为简化操作，待会将节点1生成的所有文件拷贝到节点2和节点3.

1. 创建工作目录并解压二进制包

mkdir /opt/etcd/{bin,cfg,ssl} -p
tar zxvf etcd-v3.4.9-linux-amd64.tar.gz
mv etcd-v3.4.9-linux-amd64/{etcd,etcdctl} /opt/etcd/bin/

2. 创建etcd配置文件

# 61 服务器
cat > /opt/etcd/cfg/etcd.conf << EOF
#[Member]
ETCD_NAME="etcd-1"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.100.61:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.100.61:2379"

#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.100.61:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.100.61:2379"
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.100.61:2380,etcd-2=https://192.168.100.62:2380,etcd-3=https://192.168.100.63:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
EOF

#62 服务器
cat > /opt/etcd/cfg/etcd.conf << EOF
#[Member]
ETCD_NAME="etcd-2"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.100.62:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.100.62:2379"

#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.100.62:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.100.62:2379"
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.100.61:2380,etcd-2=https://192.168.100.62:2380,etcd-3=https://192.168.100.63:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
EOF


#63 服务器
cat > /opt/etcd/cfg/etcd.conf << EOF
#[Member]
ETCD_NAME="etcd-3"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.100.63:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.100.63:2379"

#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.100.63:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.100.63:2379"
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.100.61:2380,etcd-2=https://192.168.100.62:2380,etcd-3=https://192.168.100.63:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
EOF

ETCD_NAME：节点名称，集群中唯一
ETCD_DATA_DIR：数据目录
ETCD_LISTEN_PEER_URLS：集群通信监听地址
ETCD_LISTEN_CLIENT_URLS：客户端访问监听地址
ETCD_INITIAL_ADVERTISE_PEERURLS：集群通告地址
ETCD_ADVERTISE_CLIENT_URLS：客户端通告地址
ETCD_INITIAL_CLUSTER：集群节点地址
ETCD_INITIALCLUSTER_TOKEN：集群Token
ETCD_INITIALCLUSTER_STATE：加入集群的当前状态，new是新集群，existing表示加入已有集群

3. systemd管理etcd

原来的代码，有问题

cat > /usr/lib/systemd/system/etcd.service << EOF
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target

[Service]
Type=notify
EnvironmentFile=/opt/etcd/cfg/etcd.conf
ExecStart=/opt/etcd/bin/etcd \
--cert-file=/opt/etcd/ssl/server.pem \
--key-file=/opt/etcd/ssl/server-key.pem \
--peer-cert-file=/opt/etcd/ssl/server.pem \
--peer-key-file=/opt/etcd/ssl/server-key.pem \
--trusted-ca-file=/opt/etcd/ssl/ca.pem \
--peer-trusted-ca-file=/opt/etcd/ssl/ca.pem \
--logger=zap
Restart=on-failure
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

4. 拷贝刚才生成的证书

把刚才生成的证书拷贝到配置文件中的路径：

[root@k8s-node2 cfg]# cp ~/TLS/etcd/ca*pem ~/TLS/etcd/server*pem /opt/etcd/ssl/
[root@k8s-node2 cfg]# ll /opt/etcd/ssl/
total 16
-rw-------. 1 root root 1675 Dec 12 04:40 ca-key.pem
-rw-r--r--. 1 root root 1265 Dec 12 04:40 ca.pem
-rw-------. 1 root root 1675 Dec 12 04:40 server-key.pem
-rw-r--r--. 1 root root 1363 Dec 12 04:40 server.pem

在这里插入图片描述

5. 启动并设置开机启动

systemctl daemon-reload
systemctl start etcd && systemctl enable etcd

#启动示例如下：

[root@k8s-node2 ~]# systemctl daemon-reload

[root@k8s-node2 ~]# systemctl start etcd && systemctl enable etcd #启动etcd
Created symlink from /etc/systemd/system/multi-user.target.wants/etcd.service to /usr/lib/systemd/system/etcd.service.

[root@k8s-node2 ~]# systemctl status etcd.service #查看etcd状态
● etcd.service - Etcd Server
   Loaded: loaded (/usr/lib/systemd/system/etcd.service; enabled; vendor preset: disabled)
   Active: active (running) since Tue 2021-12-14 17:18:03 CST; 3s ago
 Main PID: 2518 (etcd)
   CGroup: /system.slice/etcd.service
           └─2518 /opt/etcd/bin/etcd --cert-file=/opt/etcd/ssl/server.pem --key-file=/opt/etcd/ssl/server-key.pem --peer-cert-file=/opt/etcd/ssl/...

Dec 14 17:18:03 k8s-node2 etcd[2518]: {"level":"info","ts":"2021-12-14T17:18:03.401+0800","caller":"rafthttp/stream.go:425","msg":"establ...630fe0"}
Dec 14 17:18:03 k8s-node2 etcd[2518]: {"level":"info","ts":"2021-12-14T17:18:03.402+0800","caller":"rafthttp/stream.go:425","msg":"establ...630fe0"}
Dec 14 17:18:03 k8s-node2 etcd[2518]: {"level":"info","ts":"2021-12-14T17:18:03.410+0800","caller":"membership/cluster.go:558","msg":"set...":"3.0"}
Dec 14 17:18:03 k8s-node2 etcd[2518]: {"level":"info","ts":"2021-12-14T17:18:03.410+0800","caller":"api/capability.go:76","msg":"enabled ...":"3.0"}
Dec 14 17:18:03 k8s-node2 etcd[2518]: {"level":"info","ts":"2021-12-14T17:18:03.412+0800","caller":"etcdserver/server.go:2036","msg":"published l...
Dec 14 17:18:03 k8s-node2 systemd[1]: Started Etcd Server.
Dec 14 17:18:03 k8s-node2 etcd[2518]: {"level":"info","ts":"2021-12-14T17:18:03.413+0800","caller":"embed/serve.go:191","msg":"serving cl...3:2379"}
Dec 14 17:18:03 k8s-node2 etcd[2518]: {"level":"info","ts":"2021-12-14T17:18:03.442+0800","caller":"etcdserver/server.go:715","msg":"initialized ...
Dec 14 17:18:05 k8s-node2 etcd[2518]: {"level":"info","ts":"2021-12-14T17:18:05.180+0800","caller":"membership/cluster.go:546","msg":"upd...":"3.4"}
Dec 14 17:18:05 k8s-node2 etcd[2518]: {"level":"info","ts":"2021-12-14T17:18:05.180+0800","caller":"api/capability.go:76","msg":"enabled ...":"3.4"}
Hint: Some lines were ellipsized, use -l to show in full.
[root@k8s-node2 ~]#
[root@k8s-node2 ~]#

6. 将上面节点1所有生成的文件拷贝到节点2和节点3

scp -r /opt/etcd/ root@192.168.100.62:/opt/
scp /usr/lib/systemd/system/etcd.service root@192.168.100.62:/usr/lib/systemd/system/
scp -r /opt/etcd/ root@192.168.100.63:/opt/
scp /usr/lib/systemd/system/etcd.service root@192.168.100.63:/usr/lib/systemd/system/

然后在节点2和节点3分别修改etcd.conf配置文件中的节点名称和当前服务器IP：

vi /opt/etcd/cfg/etcd.conf
#[Member]
ETCD_NAME="etcd-1"   # 修改此处，节点2改为etcd-2，节点3改为etcd-3
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.100.61:2380"   # 修改此处为当前服务器IP
ETCD_LISTEN_CLIENT_URLS="https://192.168.100.61:2379" # 修改此处为当前服务器IP

#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.100.61:2380" # 修改此处为当前服务器IP
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.100.61:2379" # 修改此处为当前服务器IP
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.100.61:2380,etcd-2=https://192.168.100.62:2380,etcd-3=https://192.168.100.63:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"

最后启动etcd并设置开机启动，同上。

7. 查看集群状态

/opt/etcd/bin/etcdctl --cacert=/opt/etcd/ssl/ca.pem --cert=/opt/etcd/ssl/server.pem --key=/opt/etcd/ssl/server-key.pem --endpoints="https://192.168.100.61:2379,https://192.168.100.62:2379,https://192.168.100.63:2379" endpoint health --write-out=table

+----------------------------+--------+-------------+-------+
|          ENDPOINT    | HEALTH |    TOOK     | ERROR |
+----------------------------+--------+-------------+-------+
| https://192.168.100.61:2379 |   true | 10.301506ms |    |
| https://192.168.100.63:2379 |   true | 12.87467ms |     |
| https://192.168.100.62:2379 |   true | 13.225954ms |    |
+----------------------------+--------+-------------+-------+

如果输出上面信息，就说明集群部署成功。
如果有问题第一步先看日志：/var/log/message 或 journalctl -u etcd

三、安装Docker

这里使用Docker作为容器引擎，也可以换成别的，例如containerd
下载地址：

wget https://download.docker.com/linux/static/stable/x86_64/docker-19.03.9.tgz

scp docker-19.03.9.tgz root@192.168.100.62:/root/
scp docker-19.03.9.tgz root@192.168.100.63:/root/

以下在所有节点操作。这里采用二进制安装，用yum安装也一样。

3.1 解压二进制包

tar zxvf docker-19.03.9.tgz
mv docker/* /usr/bin

3.2 systemd管理docker

cat > /usr/lib/systemd/system/docker.service << EOF
[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
After=network-online.target firewalld.service
Wants=network-online.target

[Service]
Type=notify
ExecStart=/usr/bin/dockerd
ExecReload=/bin/kill -s HUP $MAINPID
LimitNOFILE=infinity
LimitNPROC=infinity
LimitCORE=infinity
TimeoutStartSec=0
Delegate=yes
KillMode=process
Restart=on-failure
StartLimitBurst=3
StartLimitInterval=60s

[Install]
WantedBy=multi-user.target
EOF

3.3 创建配置文件

mkdir /etc/docker
cat > /etc/docker/daemon.json << EOF
{
  "registry-mirrors": ["https://b9pmyelo.mirror.aliyuncs.com"]
}
EOF
  • registry-mirrors 阿里云镜像加速器

3.4 启动并设置开机启动

systemctl daemon-reload
systemctl start docker && systemctl enable docker

四、部署Master Node

如果你在学习中遇到问题或者文档有误可联系阿良~ 微信: k8init

4.1 生成kube-apiserver证书

1. 自签证书颁发机构（CA）

cd ~/TLS/k8s

cat > ca-config.json << EOF
{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "kubernetes": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}
EOF
cat > ca-csr.json << EOF
{
    "CN": "kubernetes",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing",
            "O": "k8s",
            "OU": "System"
        }
    ]
}
EOF

生成证书：

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

会生成ca.pem和ca-key.pem文件。

2. 使用自签CA签发kube-apiserver HTTPS证书

创建证书申请文件：

cat > server-csr.json << EOF
{
    "CN": "kubernetes",
    "hosts": [
      "10.0.0.1",
      "127.0.0.1",
      "192.168.100.61",
      "192.168.100.62",
      "192.168.100.63",
      "192.168.100.64",
      "192.168.100.65",
      "192.168.100.66",
      "192.168.100.67",
      "kubernetes",
      "kubernetes.default",
      "kubernetes.default.svc",
      "kubernetes.default.svc.cluster",
      "kubernetes.default.svc.cluster.local"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "BeiJing",
            "ST": "BeiJing",
            "O": "k8s",
            "OU": "System"
        }
    ]
}
EOF

注：上述文件hosts字段中IP为所有Master/LB/VIP IP，一个都不能少！为了方便后期扩容可以多写几个预留的IP。
生成证书：

cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes server-csr.json | cfssljson -bare server

会生成server.pem和server-key.pem文件。

4.2 从Github下载二进制文件

下载地址： https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.20.md
在这里插入图片描述
在这里插入图片描述

wget https://dl.k8s.io/v1.20.13/kubernetes-server-linux-amd64.tar.gz

注：打开链接你会发现里面有很多包，下载一个server包就够了，包含了Master和Worker Node二进制文件。

4.3 解压二进制包

mkdir -p /opt/kubernetes/{bin,cfg,ssl,logs} 
tar zxvf kubernetes-server-linux-amd64.tar.gz
cd kubernetes/server/bin
cp kube-apiserver kube-scheduler kube-controller-manager /opt/kubernetes/bin
cp kubectl /usr/bin/

4.4 部署kube-apiserver(master)

1. 创建配置文件

cat > /opt/kubernetes/cfg/kube-apiserver.conf << EOF
KUBE_APISERVER_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--etcd-servers=https://192.168.100.61:2379,https://192.168.100.62:2379,https://192.168.100.63:2379 \\
--bind-address=192.168.100.61 \\
--secure-port=6443 \\
--advertise-address=192.168.100.61 \\
--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=/opt/kubernetes/cfg/token.csv \\
--service-node-port-range=30000-32767 \\
--kubelet-client-certificate=/opt/kubernetes/ssl/server.pem \\
--kubelet-client-key=/opt/kubernetes/ssl/server-key.pem \\
--tls-cert-file=/opt/kubernetes/ssl/server.pem  \\
--tls-private-key-file=/opt/kubernetes/ssl/server-key.pem \\
--client-ca-file=/opt/kubernetes/ssl/ca.pem \\
--service-account-key-file=/opt/kubernetes/ssl/ca-key.pem \\
--service-account-issuer=api \\
--service-account-signing-key-file=/opt/kubernetes/ssl/server-key.pem \\
--etcd-cafile=/opt/etcd/ssl/ca.pem \\
--etcd-certfile=/opt/etcd/ssl/server.pem \\
--etcd-keyfile=/opt/etcd/ssl/server-key.pem \\
--requestheader-client-ca-file=/opt/kubernetes/ssl/ca.pem \\
--proxy-client-cert-file=/opt/kubernetes/ssl/server.pem \\
--proxy-client-key-file=/opt/kubernetes/ssl/server-key.pem \\
--requestheader-allowed-names=kubernetes \\
--requestheader-extra-headers-prefix=X-Remote-Extra- \\
--requestheader-group-headers=X-Remote-Group \\
--requestheader-username-headers=X-Remote-User \\
--enable-aggregator-routing=true \\
--audit-log-maxage=30 \\
--audit-log-maxbackup=3 \\
--audit-log-maxsize=100 \\
--audit-log-path=/opt/kubernetes/logs/k8s-audit.log"
EOF

注：上面两个\ \ 第一个是转义符，第二个是换行符，使用转义符是为了使用EOF保留换行符。

–logtostderr：启用日志
–v：日志等级
–log-dir：日志目录
–etcd-servers：etcd集群地址
–bind-address：监听地址
–secure-port：https安全端口
–advertise-address：集群通告地址
–allow-privileged：启用授权
–service-cluster-ip-range：Service虚拟IP地址段
–enable-admission-plugins：准入控制模块
–authorization-mode：认证授权，启用RBAC授权和节点自管理
–enable-bootstrap-token-auth：启用TLS bootstrap机制
–token-auth-file：bootstrap token文件
–service-node-port-range：Service nodeport类型默认分配端口范围
–kubelet-client-xxx：apiserver访问kubelet客户端证书
–tls-xxx-file：apiserver https证书
1.20版本必须加的参数：–service-account-issuer，–service-account-signing-key-file
–etcd-xxxfile：连接Etcd集群证书
–audit-log-xxx：审计日志
启动聚合层相关配置：–requestheader-client-ca-file，–proxy-client-cert-file，–proxy-client-key-file，–requestheader-allowed-names，–requestheader-extra-headers-prefix，–requestheader-group-headers，–requestheader-username-headers，–enable-aggregator-routing

2. 拷贝刚才生成的证书

把刚才生成的证书拷贝到配置文件中的路径：

cp ~/TLS/k8s/ca*pem ~/TLS/k8s/server*pem /opt/kubernetes/ssl/

3. 启用 TLS Bootstrapping 机制

TLS Bootstraping：Master apiserver启用TLS认证后，Node节点kubelet和kube-proxy要与kube-apiserver进行通信，必须使用CA签发的有效证书才可以，当Node节点很多时，这种客户端证书颁发需要大量工作，同样也会增加集群扩展复杂度。为了简化流程，Kubernetes引入了TLS bootstraping机制来自动颁发客户端证书，kubelet会以一个低权限用户自动向apiserver申请证书，kubelet的证书由apiserver动态签署。所以强烈建议在Node上使用这种方式，目前主要用于kubelet，kube-proxy还是由我们统一颁发一个证书。
TLS bootstraping 工作流程：
在这里插入图片描述

创建上述配置文件中token文件：

cat > /opt/kubernetes/cfg/token.csv << EOF
c47ffb939f5ca36231d9e3121a252940,kubelet-bootstrap,10001,"system:node-bootstrapper"
EOF

格式：token，用户名，UID，用户组
token也可自行生成替换：

head -c 16 /dev/urandom | od -An -t x | tr -d ' '

4. systemd管理apiserver

cat > /usr/lib/systemd/system/kube-apiserver.service << EOF
[Unit]
Description=Kubernetes API Server
Documentation=https://github.com/kubernetes/kubernetes

[Service]
EnvironmentFile=/opt/kubernetes/cfg/kube-apiserver.conf
ExecStart=/opt/kubernetes/bin/kube-apiserver \$KUBE_APISERVER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

5. 启动并设置开机启动

[root@k8s-master1 bin]# systemctl daemon-reload
[root@k8s-master1 bin]# systemctl start kube-apiserver && systemctl enable kube-apiserver

[root@k8s-master1 bin]# ps -ef|grep kube-apiserver
root      12328      1 52 16:53 ?        00:00:05 /opt/kubernetes/bin/kube-apiserver --logtostderr=false --v=2 --log-dir=/opt/kubernetes/logs --etcd-servers=https://192.168.100.61:2379,https://192.168.100.62:2379,https://192.168.100.63:2379 --bind-address=192.168.100.61 --secure-port=6443 --advertise-address=192.168.100.61 --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=/opt/kubernetes/cfg/token.csv --service-node-port-range=30000-32767 --kubelet-client-certificate=/opt/kubernetes/ssl/server.pem --kubelet-client-key=/opt/kubernetes/ssl/server-key.pem --tls-cert-file=/opt/kubernetes/ssl/server.pem --tls-private-key-file=/opt/kubernetes/ssl/server-key.pem --client-ca-file=/opt/kubernetes/ssl/ca.pem --service-account-key-file=/opt/kubernetes/ssl/ca-key.pem --service-account-issuer=api --service-account-signing-key-file=/opt/kubernetes/ssl/server-key.pem --etcd-cafile=/opt/etcd/ssl/ca.pem --etcd-certfile=/opt/etcd/ssl/server.pem --etcd-keyfile=/opt/etcd/ssl/server-key.pem --requestheader-client-ca-file=/opt/kubernetes/ssl/ca.pem --proxy-client-cert-file=/opt/kubernetes/ssl/server.pem --proxy-client-key-file=/opt/kubernetes/ssl/server-key.pem --requestheader-allowed-names=kubernetes --requestheader-extra-headers-prefix=X-Remote-Extra- --requestheader-group-headers=X-Remote-Group --requestheader-username-headers=X-Remote-User --enable-aggregator-routing=true --audit-log-maxage=30 --audit-log-maxbackup=3 --audit-log-maxsize=100 --audit-log-path=/opt/kubernetes/logs/k8s-audit.log
root      12368  11582  0 16:53 pts/1    00:00:00 grep --color=auto kube-apiserver
[root@k8s-master1 bin]#

# 或者如下操作
[root@k8s-master1 bin]# systemctl status kube-apiserver
● kube-apiserver.service - Kubernetes API Server
   Loaded: loaded (/usr/lib/systemd/system/kube-apiserver.service; enabled; vendor preset: disabled)
   Active: active (running) since Tue 2021-12-14 17:33:43 CST; 25s ago
     Docs: https://github.com/kubernetes/kubernetes
 Main PID: 3154 (kube-apiserver)
   CGroup: /system.slice/kube-apiserver.service
           └─3154 /opt/kubernetes/bin/kube-apiserver --logtostderr=false --v=2 --log-dir=/opt/kubernetes/logs --etcd-servers=https://192.168.100....

Dec 14 17:33:43 k8s-master1 systemd[1]: Started Kubernetes API Server.
Dec 14 17:33:43 k8s-master1 kube-apiserver[3154]: E1214 17:33:43.605426    3154 instance.go:392] Could not construct pre-rendered response...ot: api
Dec 14 17:33:45 k8s-master1 kube-apiserver[3154]: E1214 17:33:45.909923    3154 controller.go:152] Unable to remove old endpoints from kub...rorMsg:
Hint: Some lines were ellipsized, use -l to show in full.
[root@k8s-master1 bin]#

4.5 部署kube-controller-manager

1. 创建配置文件

cat > /opt/kubernetes/cfg/kube-controller-manager.conf << EOF
KUBE_CONTROLLER_MANAGER_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--leader-elect=true \\
--kubeconfig=/opt/kubernetes/cfg/kube-controller-manager.kubeconfig \\
--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=/opt/kubernetes/ssl/ca.pem \\
--cluster-signing-key-file=/opt/kubernetes/ssl/ca-key.pem  \\
--root-ca-file=/opt/kubernetes/ssl/ca.pem \\
--service-account-private-key-file=/opt/kubernetes/ssl/ca-key.pem \\
--cluster-signing-duration=87600h0m0s"
EOF

–kubeconfig：连接apiserver配置文件
–leader-elect：当该组件启动多个时，自动选举（HA）
–cluster-signing-cert-file/–cluster-signing-key-file：自动为kubelet颁发证书的CA，与apiserver保持一致

2. 生成kubeconfig文件

生成kube-controller-manager证书：

# 切换工作目录
cd ~/TLS/k8s

# 创建证书请求文件
cat > kube-controller-manager-csr.json << EOF
{
  "CN": "system:kube-controller-manager",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "L": "BeiJing", 
      "ST": "BeiJing",
      "O": "system:masters",
      "OU": "System"
    }
  ]
}
EOF

# 生成证书
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-controller-manager-csr.json | cfssljson -bare kube-controller-manager

生成kubeconfig文件（以下是shell命令，直接在终端执行）：

KUBE_CONFIG="/opt/kubernetes/cfg/kube-controller-manager.kubeconfig"
KUBE_APISERVER="https://192.168.100.61:6443"

kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials kube-controller-manager \
  --client-certificate=./kube-controller-manager.pem \
  --client-key=./kube-controller-manager-key.pem \
  --embed-certs=true \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kube-controller-manager \
  --kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}

执行效果demo：

[root@k8s-master1 k8s]# KUBE_CONFIG="/opt/kubernetes/cfg/kube-controller-manager.kubeconfig"
[root@k8s-master1 k8s]# KUBE_APISERVER="https://192.168.100.61:6443"
[root@k8s-master1 k8s]#
[root@k8s-master1 k8s]# kubectl config set-cluster kubernetes \
>   --certificate-authority=/opt/kubernetes/ssl/ca.pem \
>   --embed-certs=true \
>   --server=${KUBE_APISERVER} \
>   --kubeconfig=${KUBE_CONFIG}
Cluster "kubernetes" set.
[root@k8s-master1 k8s]# kubectl config set-credentials kube-controller-manager \
>   --client-certificate=./kube-controller-manager.pem \
>   --client-key=./kube-controller-manager-key.pem \
>   --embed-certs=true \
>   --kubeconfig=${KUBE_CONFIG}
User "kube-controller-manager" set.
[root@k8s-master1 k8s]# kubectl config set-context default \
>   --cluster=kubernetes \
>   --user=kube-controller-manager \
>   --kubeconfig=${KUBE_CONFIG}
Context "default" created.
[root@k8s-master1 k8s]# kubectl config use-context default --kubeconfig=${KUBE_CONFIG}
Switched to context "default".
[root@k8s-master1 k8s]# 
[root@k8s-master1 k8s]# ll /opt/kubernetes/cfg/
total 20
-rw-r--r--. 1 root root 1709 Dec 12 16:51 kube-apiserver.conf
-rw-r--r--. 1 root root  582 Dec 12 16:55 kube-controller-manager.conf
-rw-------. 1 root root 6344 Dec 12 16:56 kube-controller-manager.kubeconfig
-rw-r--r--. 1 root root   84 Dec 12 16:52 token.csv
[root@k8s-master1 k8s]#

3. systemd管理controller-manager

cat > /usr/lib/systemd/system/kube-controller-manager.service << EOF
[Unit]
Description=Kubernetes Controller Manager
Documentation=https://github.com/kubernetes/kubernetes

[Service]
EnvironmentFile=/opt/kubernetes/cfg/kube-controller-manager.conf
ExecStart=/opt/kubernetes/bin/kube-controller-manager \$KUBE_CONTROLLER_MANAGER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

4. 启动并设置开机启动

[root@k8s-master1 k8s]# systemctl daemon-reload
[root@k8s-master1 k8s]# systemctl start kube-controller-manager && systemctl enable kube-controller-manager
[root@k8s-master1 k8s]#
[root@k8s-master1 k8s]# ps -ef|grep kube-controller-manager
root      12601      1  1 17:00 ?        00:03:55 /opt/kubernetes/bin/kube-controller-manager --logtostderr=false --v=2 --log-dir=/opt/kubernetes/logs --leader-elect=true --kubeconfig=/opt/kubernetes/cfg/kube-controller-manager.kubeconfig --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=/opt/kubernetes/ssl/ca.pem --cluster-signing-key-file=/opt/kubernetes/ssl/ca-key.pem --root-ca-file=/opt/kubernetes/ssl/ca.pem --service-account-private-key-file=/opt/kubernetes/ssl/ca-key.pem --cluster-signing-duration=87600h0m0s
root      18343  13439  0 20:53 pts/1    00:00:00 grep --color=auto kube-controller-manager
[root@k8s-master1 k8s]#



[root@k8s-master1 k8s]# systemctl status kube-controller-manager
● kube-controller-manager.service - Kubernetes Controller Manager
   Loaded: loaded (/usr/lib/systemd/system/kube-controller-manager.service; enabled; vendor preset: disabled)
   Active: active (running) since Tue 2021-12-14 17:35:47 CST; 11s ago
     Docs: https://github.com/kubernetes/kubernetes
 Main PID: 3287 (kube-controller)
   CGroup: /system.slice/kube-controller-manager.service
           └─3287 /opt/kubernetes/bin/kube-controller-manager --logtostderr=false --v=2 --log-dir=/opt/kubernetes/logs --leader-elect=true --kube...

Dec 14 17:35:47 k8s-master1 systemd[1]: Started Kubernetes Controller Manager.
Dec 14 17:35:48 k8s-master1 kube-controller-manager[3287]: E1214 17:35:48.652536    3287 core.go:232] failed to start cloud node lifecycle ...ovided
Dec 14 17:35:48 k8s-master1 kube-controller-manager[3287]: E1214 17:35:48.655317    3287 core.go:92] Failed to start service controller: WA...l fail
Hint: Some lines were ellipsized, use -l to show in full.
[root@k8s-master1 k8s]#

4.6 部署kube-scheduler

1. 创建配置文件

cat > /opt/kubernetes/cfg/kube-scheduler.conf << EOF
KUBE_SCHEDULER_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--leader-elect \\
--kubeconfig=/opt/kubernetes/cfg/kube-scheduler.kubeconfig \\
--bind-address=127.0.0.1"
EOF

–kubeconfig：连接apiserver配置文件
–leader-elect：当该组件启动多个时，自动选举（HA）

2. 生成kubeconfig文件

生成kube-scheduler证书：

# 切换工作目录
cd ~/TLS/k8s

# 创建证书请求文件
cat > kube-scheduler-csr.json << EOF
{
  "CN": "system:kube-scheduler",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "L": "BeiJing",
      "ST": "BeiJing",
      "O": "system:masters",
      "OU": "System"
    }
  ]
}
EOF

# 生成证书
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-scheduler-csr.json | cfssljson -bare kube-scheduler

生成kubeconfig文件：

KUBE_CONFIG="/opt/kubernetes/cfg/kube-scheduler.kubeconfig"
KUBE_APISERVER="https://192.168.100.61:6443"

kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials kube-scheduler \
  --client-certificate=./kube-scheduler.pem \
  --client-key=./kube-scheduler-key.pem \
  --embed-certs=true \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kube-scheduler \
  --kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}

3. systemd管理scheduler

cat > /usr/lib/systemd/system/kube-scheduler.service << EOF
[Unit]
Description=Kubernetes Scheduler
Documentation=https://github.com/kubernetes/kubernetes

[Service]
EnvironmentFile=/opt/kubernetes/cfg/kube-scheduler.conf
ExecStart=/opt/kubernetes/bin/kube-scheduler \$KUBE_SCHEDULER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

4. 启动并设置开机启动

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


● kube-scheduler.service - Kubernetes Scheduler
   Loaded: loaded (/usr/lib/systemd/system/kube-scheduler.service; enabled; vendor preset: disabled)
   Active: active (running) since Tue 2021-12-14 17:37:07 CST; 8s ago
     Docs: https://github.com/kubernetes/kubernetes
 Main PID: 3406 (kube-scheduler)
   CGroup: /system.slice/kube-scheduler.service
           └─3406 /opt/kubernetes/bin/kube-scheduler --logtostderr=false --v=2 --log-dir=/opt/kubernetes/logs --leader-elect --kubeconfig=/opt/ku...

Dec 14 17:37:07 k8s-master1 systemd[1]: Started Kubernetes Scheduler.
[root@k8s-master1 k8s]#

5. 查看集群状态

生成kubectl连接集群的证书：

cat > admin-csr.json <<EOF
{
  "CN": "admin",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "L": "BeiJing",
      "ST": "BeiJing",
      "O": "system:masters",
      "OU": "System"
    }
  ]
}
EOF

cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes admin-csr.json | cfssljson -bare admin

生成kubeconfig文件：

mkdir /root/.kube

KUBE_CONFIG="/root/.kube/config"
KUBE_APISERVER="https://192.168.100.61:6443"

kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials cluster-admin \
  --client-certificate=./admin.pem \
  --client-key=./admin-key.pem \
  --embed-certs=true \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
  --cluster=kubernetes \
  --user=cluster-admin \
  --kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}

通过kubectl工具查看当前集群组件状态：

kubectl get cs
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"}

如上输出说明Master节点组件运行正常。

6. 授权kubelet-bootstrap用户允许请求证书

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

如果提示已存在，参考

五、部署Worker Node

如果你在学习中遇到问题或者文档有误可联系阿良~ 微信: k8init
下面还是在Master Node上操作，即同时作为Worker Node

5.1 创建工作目录并拷贝二进制文件

在所有worker node创建工作目录：【Node】

mkdir -p /opt/kubernetes/{bin,cfg,ssl,logs} 
mkdir -p kubernetes/server/bin

在master上操作

cd ~/kubernetes/server/bin
cp kubelet kube-proxy /opt/kubernetes/bin   # 需要提前将Master中的/opt/kubernetes/bin/*复制过来，

5.2 部署kubelet

1. 创建配置文件

cat > /opt/kubernetes/cfg/kubelet.conf << EOF
KUBELET_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--hostname-override=k8s-master1 \\
--network-plugin=cni \\
--kubeconfig=/opt/kubernetes/cfg/kubelet.kubeconfig \\
--bootstrap-kubeconfig=/opt/kubernetes/cfg/bootstrap.kubeconfig \\
--config=/opt/kubernetes/cfg/kubelet-config.yml \\
--cert-dir=/opt/kubernetes/ssl \\
--pod-infra-container-image=lizhenliang/pause-amd64:3.0"
EOF

–hostname-override：显示名称，集群中唯一
–network-plugin：启用CNI
–kubeconfig：空路径，会自动生成，后面用于连接apiserver
–bootstrap-kubeconfig：首次启动向apiserver申请证书
–config：配置参数文件
–cert-dir：kubelet证书生成目录
–pod-infra-container-image：管理Pod网络容器的镜像

2. 配置参数文件

cat > /opt/kubernetes/cfg/kubelet-config.yml << EOF
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
address: 0.0.0.0
port: 10250
readOnlyPort: 10255
cgroupDriver: cgroupfs
clusterDNS:
- 10.0.0.2
clusterDomain: cluster.local 
failSwapOn: false
authentication:
  anonymous:
    enabled: false
  webhook:
    cacheTTL: 2m0s
    enabled: true
  x509:
    clientCAFile: /opt/kubernetes/ssl/ca.pem 
authorization:
  mode: Webhook
  webhook:
    cacheAuthorizedTTL: 5m0s
    cacheUnauthorizedTTL: 30s
evictionHard:
  imagefs.available: 15%
  memory.available: 100Mi
  nodefs.available: 10%
  nodefs.inodesFree: 5%
maxOpenFiles: 1000000
maxPods: 110
EOF

3. 生成kubelet初次加入集群引导kubeconfig文件【master中执行，把得到的文件传到Node中】

KUBE_CONFIG="/opt/kubernetes/cfg/bootstrap.kubeconfig"
KUBE_APISERVER="https://192.168.100.61:6443" # apiserver IP:PORT
TOKEN="c47ffb939f5ca36231d9e3121a252940" # 与token.csv里保持一致 master中存储位置/opt/kubernetes/cfg/token.csv

# 生成 kubelet bootstrap kubeconfig 配置文件
kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials "kubelet-bootstrap" \
  --token=${TOKEN} \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
  --cluster=kubernetes \
  --user="kubelet-bootstrap" \
  --kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}

在这里插入图片描述

4. systemd管理kubelet

cat > /usr/lib/systemd/system/kubelet.service << EOF
[Unit]
Description=Kubernetes Kubelet
After=docker.service

[Service]
EnvironmentFile=/opt/kubernetes/cfg/kubelet.conf
ExecStart=/opt/kubernetes/bin/kubelet \$KUBELET_OPTS
Restart=on-failure
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

5. 启动并设置开机启动

[root@k8s-node1 cfg]# systemctl daemon-reload
[root@k8s-node1 cfg]# systemctl start kubelet && systemctl enable kubelet
[root@k8s-node1 cfg]# systemctl status kubelet
● kubelet.service - Kubernetes Kubelet
   Loaded: loaded (/usr/lib/systemd/system/kubelet.service; enabled; vendor preset: disabled)
   Active: active (running) since Mon 2021-12-13 16:44:45 PST; 9s ago
 Main PID: 39675 (kubelet)
    Tasks: 7
   Memory: 114.0M
   CGroup: /system.slice/kubelet.service
           └─39675 /opt/kubernetes/bin/kubelet --logtostderr=false --v=2 --log-dir=/opt/kubernetes/logs --hostname-override=k8s-master1 --network-plugin=cni --kubeconfig...

Dec 13 16:44:45 k8s-node1 systemd[1]: Started Kubernetes Kubelet.
[root@k8s-node1 cfg]#

在这里插入图片描述

5.3 批准kubelet证书申请并加入集群[Master中操作]

# 查看kubelet证书请求
[root@k8s-master1 cfg]# kubectl get csr
NAME                                                   AGE   SIGNERNAME                                    REQUESTOR           CONDITION
node-csr-h1NVsKZinTNyFXXzmUt1hqnuBxJA1Do-ueh6HkXTh1g   51s   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending

# 批准申请
[root@k8s-master1 cfg]#
[root@k8s-master1 cfg]# kubectl certificate approve node-csr-h1NVsKZinTNyFXXzmUt1hqnuBxJA1Do-ueh6HkXTh1g
certificatesigningrequest.certificates.k8s.io/node-csr-TCzj1DLD2assioRywrCeVN9zM-xZdCS4MD8tFRgMAfk approved

# 查看节点
[root@k8s-master1 cfg]# kubectl get node
NAME          STATUS     ROLES    AGE   VERSION
k8s-master1   NotReady   <none>   24s   v1.20.13

在这里插入图片描述
注：由于网络插件还没有部署，节点会没有准备就绪 NotReady

5.4 部署kube-proxy

1. 创建配置文件

cat > /opt/kubernetes/cfg/kube-proxy.conf << EOF
KUBE_PROXY_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--config=/opt/kubernetes/cfg/kube-proxy-config.yml"
EOF

2. 配置参数文件

cat > /opt/kubernetes/cfg/kube-proxy-config.yml << EOF
kind: KubeProxyConfiguration
apiVersion: kubeproxy.config.k8s.io/v1alpha1
bindAddress: 0.0.0.0
metricsBindAddress: 0.0.0.0:10249
clientConnection:
  kubeconfig: /opt/kubernetes/cfg/kube-proxy.kubeconfig
hostnameOverride: k8s-master1
clusterCIDR: 10.244.0.0/16
EOF

3. 生成kube-proxy.kubeconfig文件【Master】

# 切换工作目录
cd ~/TLS/k8s

# 创建证书请求文件
cat > kube-proxy-csr.json << EOF
{
  "CN": "system:kube-proxy",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "L": "BeiJing",
      "ST": "BeiJing",
      "O": "k8s",
      "OU": "System"
    }
  ]
}
EOF

# 生成证书
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-proxy-csr.json | cfssljson -bare kube-proxy

生成kubeconfig文件：

KUBE_CONFIG="/opt/kubernetes/cfg/kube-proxy.kubeconfig"
KUBE_APISERVER="https://192.168.100.61:6443"

kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials kube-proxy \
  --client-certificate=./kube-proxy.pem \
  --client-key=./kube-proxy-key.pem \
  --embed-certs=true \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kube-proxy \
  --kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}

delete ===== 把/opt/kubernetes/cfg/kube-proxy.kubeconfig传到Node节点

delete =====    [root@k8s-master1 k8s]# scp /opt/kubernetes/cfg/kube-proxy.kubeconfig root@192.168.100.62:/opt/kubernetes/cfg/
delete =====    root@192.168.100.62's password:
delete =====    kube-proxy.kubeconfig

4. systemd管理kube-proxy

cat > /usr/lib/systemd/system/kube-proxy.service << EOF
[Unit]
Description=Kubernetes Proxy
After=network.target

[Service]
EnvironmentFile=/opt/kubernetes/cfg/kube-proxy.conf
ExecStart=/opt/kubernetes/bin/kube-proxy \$KUBE_PROXY_OPTS
Restart=on-failure
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

5. 启动并设置开机启动【Node】

systemctl daemon-reload && systemctl start kube-proxy && systemctl enable kube-proxy

[root@k8s-node1 cfg]# systemctl daemon-reload && systemctl start kube-proxy && systemctl enable kube-proxy
Created symlink from /etc/systemd/system/multi-user.target.wants/kube-proxy.service to /usr/lib/systemd/system/kube-proxy.service.

[root@k8s-node1 cfg]# systemctl status kube-proxy
● kube-proxy.service - Kubernetes Proxy
   Loaded: loaded (/usr/lib/systemd/system/kube-proxy.service; enabled; vendor preset: disabled)
   Active: active (running) since Mon 2021-12-13 17:00:35 PST; 9s ago
 Main PID: 42943 (kube-proxy)
    Tasks: 6
   Memory: 47.9M
   CGroup: /system.slice/kube-proxy.service
           └─42943 /opt/kubernetes/bin/kube-proxy --logtostderr=false --v=2 --log-dir=/opt/kubernetes/logs --config=/opt/kubernetes/cfg/kube-proxy-config.yml

Dec 13 17:00:35 k8s-node1 systemd[1]: Started Kubernetes Proxy.
[root@k8s-node1 cfg]#

在这里插入图片描述

5.5 部署网络组件【Master】

Calico是一个纯三层的数据中心网络方案，是目前Kubernetes主流的网络方案。
部署Calico：

wget https://docs.projectcalico.org/manifests/calico.yaml
kubectl apply -f calico.yaml
kubectl get pods -n kube-system

等Calico Pod都Running，节点也会准备就绪：

kubectl get node
NAME         STATUS   ROLES    AGE   VERSION
k8s-master   Ready    <none>   37m   v1.20.4


[root@k8s-master1 k8s]# kubectl apply -f calico.yaml
configmap/calico-config created
customresourcedefinition.apiextensions.k8s.io/bgpconfigurations.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/bgppeers.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/blockaffinities.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/clusterinformations.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/felixconfigurations.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/globalnetworkpolicies.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/globalnetworksets.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/hostendpoints.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/ipamblocks.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/ipamconfigs.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/ipamhandles.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/ippools.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/kubecontrollersconfigurations.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/networkpolicies.crd.projectcalico.org created
customresourcedefinition.apiextensions.k8s.io/networksets.crd.projectcalico.org created
clusterrole.rbac.authorization.k8s.io/calico-kube-controllers created
clusterrolebinding.rbac.authorization.k8s.io/calico-kube-controllers created
clusterrole.rbac.authorization.k8s.io/calico-node created
clusterrolebinding.rbac.authorization.k8s.io/calico-node created
daemonset.apps/calico-node created
serviceaccount/calico-node created
deployment.apps/calico-kube-controllers created
serviceaccount/calico-kube-controllers created
[root@k8s-master1 k8s]#
[root@k8s-master1 k8s]# kubectl get pods -n kube-system
NAME                                      READY   STATUS    RESTARTS   AGE
calico-kube-controllers-97769f7c7-xpbvf   1/1     Running   0          3m58s
calico-node-xmhw9                         1/1     Running   0          3m58s
[root@k8s-master1 k8s]#

在这里插入图片描述

5.6 授权apiserver访问kubelet【Master】

应用场景：例如kubectl logs

cat > apiserver-to-kubelet-rbac.yaml << EOF
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
EOF

[root@k8s-master1 k8s]# kubectl apply -f apiserver-to-kubelet-rbac.yaml
clusterrole.rbac.authorization.k8s.io/system:kube-apiserver-to-kubelet created
clusterrolebinding.rbac.authorization.k8s.io/system:kube-apiserver created
[root@k8s-master1 k8s]#

5.7 新增加Worker Node

相关yml文件下载地址

1. 拷贝已部署好的Node相关文件到新节点

在Master节点将Worker Node涉及文件拷贝到新节点192.168.100.62/63

scp -r /opt/kubernetes root@192.168.100.63:/opt/

scp -r /usr/lib/systemd/system/{kubelet,kube-proxy}.service root@192.168.100.63:/usr/lib/systemd/system

scp /opt/kubernetes/ssl/ca.pem root@192.168.100.63:/opt/kubernetes/ssl

2. 删除Node节点中的kubelet证书和kubeconfig文件

rm -f /opt/kubernetes/cfg/kubelet.kubeconfig 
rm -f /opt/kubernetes/ssl/kubelet*

注：这几个文件是证书申请审批后自动生成的，每个Node不同，必须删除

3. 修改主机名

vi /opt/kubernetes/cfg/kubelet.conf
--hostname-override=k8s-node1

vi /opt/kubernetes/cfg/kube-proxy-config.yml
hostnameOverride: k8s-node1

4. 启动并设置开机启动

systemctl daemon-reload && systemctl start kubelet kube-proxy && systemctl enable kubelet kube-proxy
systemctl status kubelet kube-proxy

5. 在Master上批准新Node kubelet证书申请【Master】

# 查看证书请求
[root@k8s-master1 k8s]# kubectl get csr
NAME                                                   AGE    SIGNERNAME                                    REQUESTOR           CONDITION
node-csr-h1NVsKZinTNyFXXzmUt1hqnuBxJA1Do-ueh6HkXTh1g    116m   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Approved,Issued
node-csr-sRYKEmpGROL8OrybXHVKu8bMjYNiGM6IieT6uYJgAV8   13s    kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending
[root@k8s-master1 k8s]#

# 授权请求，使用Pending标记的那个
[root@k8s-master1 k8s]# kubectl certificate approve node-csr-h1NVsKZinTNyFXXzmUt1hqnuBxJA1Do-ueh6HkXTh1g  
certificatesigningrequest.certificates.k8s.io/node-csr-sRYKEmpGROL8OrybXHVKu8bMjYNiGM6IieT6uYJgAV8 approved
[root@k8s-master1 k8s]#

6. 查看Node状态【Master】

kubectl get node
NAME       STATUS   ROLES    AGE     VERSION
k8s-master1   Ready    <none>   47m     v1.20.4
k8s-node1    Ready    <none>   6m49s   v1.20.4

Node2（192.168.100.63 ）节点同上。记得修改主机名！

六、部署Dashboard和CoreDNS

6.1 部署Dashboard

kubectl apply -f kubernertes-dashboard.yaml
# 查看部署
kubectl get pods,svc -n kubernetes-dashboard

[root@k8s-master1 yml]# kubectl get pods,svc -n kubernetes-dashboard
NAME                                             READY   STATUS    RESTARTS   AGE
pod/dashboard-metrics-scraper-7b59f7d4df-tnhdn   1/1     Running   0          3m27s
pod/kubernetes-dashboard-5dbf55bd9d-dzkhp        1/1     Running   0          3m27s

NAME                                TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)         AGE
service/dashboard-metrics-scraper   ClusterIP   10.0.0.246   <none>        8000/TCP        3m27s
service/kubernetes-dashboard        NodePort    10.0.0.170   <none>        443:30001/TCP   3m28s
[root@k8s-master1 yml]#

在这里插入图片描述

访问地址：https://NodeIP:30001
访问地址：https://192.168.100.61:30001/#/login
创建service account并绑定默认cluster-admin管理员集群角色：

kubectl create serviceaccount dashboard-admin -n kube-system
kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kube-system:dashboard-admin
kubectl describe secrets -n kube-system $(kubectl -n kube-system get secret | awk '/dashboard-admin/{print $1}')

实际操作demo如下：


[root@k8s-master1 yml]#
[root@k8s-master1 yml]# kubectl create serviceaccount dashboard-admin -n kube-system
serviceaccount/dashboard-admin created
[root@k8s-master1 yml]# kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kube-system:dashboard-admin
clusterrolebinding.rbac.authorization.k8s.io/dashboard-admin created
[root@k8s-master1 yml]# kubectl describe secrets -n kube-system $(kubectl -n kube-system get secret | awk '/dashboard-admin/{print $1}')
Name:         dashboard-admin-token-wp2ml
Namespace:    kube-system
Labels:       <none>
Annotations:  kubernetes.io/service-account.name: dashboard-admin
              kubernetes.io/service-account.uid: 1d84b202-cdd0-4d15-a6e7-4b883114cb93

Type:  kubernetes.io/service-account-token

Data
====
ca.crt:     1359 bytes
namespace:  11 bytes
token:      eyJhbGciOiJSUzI1NiIsImtpZCI6IjJDaERFUi1sMEpibC11bkVmNUFyWk94TnRObmtLN2tfQWFZcEV6Q21Sam8ifQ.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.fw9OI6eVBP6FQ0LcGaRKA_yM5t-7YdFQCe3RNCZ2Vg0SVQPYqEVKnxrnEct_nhcKEARaGGRftGBtzsA5ASZZCL5JXxbASPP_Iwsw_n5tjmuMlGIpcPsKfM61apwVmizY4JGkMbUtuKw0g9RT6h6A3K3PuDkRdo-47yXV03kmKu731xUWaOQFdGX7vFQzpkbt_LyN_40Bl-eTAiL1sqjezQnctbPmdAGFd8ZPsh89Dq_Cc6Cr112dMl9U-eYFR-TgIIsU8dEbKBBo5_LaQf_X3-LnPzgdgaEcpc8OuRiw4_IoICWhhl8sOnGx5AGSExv7obHLeCUTfQJQmDwNRn_9Cg
[root@k8s-master1 yml]#

截图如下：
在这里插入图片描述

使用输出的token登录Dashboard。
在这里插入图片描述

6.2 部署CoreDNS

CoreDNS用于集群内部Service名称解析。

kubectl apply -f coredns.yaml 
 
kubectl get pods -n kube-system  
NAME                          READY   STATUS    RESTARTS   AGE 
coredns-5ffbfd976d-j6shb      1/1     Running   0          32s

DNS解析测试：

kubectl run -it --rm dns-test --image=busybox:1.28.4 sh 
If you don't see a command prompt, try pressing enter. 
 
/ # nslookup kubernetes 
Server:    10.0.0.2 
Address 1: 10.0.0.2 kube-dns.kube-system.svc.cluster.local 
 
Name:      kubernetes 
Address 1: 10.0.0.1 kubernetes.default.svc.cluster.local

解析没问题。
至此一个单Master集群就搭建完成了！这个环境就足以满足学习实验了，如果你的服务器配置较高，可继续扩容多Master集群！

6.3 测试kubernetes集群

在Kubernetes集群中创建一个pod，验证是否正常运行：

[root@k8s-master1 ~]# kubectl create deployment nginx --image=nginx

[root@k8s-master1 ~]# kubectl expose deployment nginx --port=80 --type=NodePort

[root@k8s-master1 ~]# kubectl get pod,svc
NAME                         READY   STATUS    RESTARTS   AGE
pod/nginx-6799fc88d8-jpqjv   1/1     Running   0          75s

NAME                 TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)        AGE
service/kubernetes   ClusterIP   10.0.0.1     <none>        443/TCP        115m
service/nginx        NodePort    10.0.0.31    <none>        80:30718/TCP   69s
[root@k8s-master1 ~]# curl http://10.0.0.31
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
html { color-scheme: light dark; }
body { width: 35em; margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif; }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>

<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>

<p><em>Thank you for using nginx.</em></p>
</body>
</html>

[参考官方文档](https://www.kubernetes.org.cn/doc-44)
[Kubernetes kubectl get 命令详解](http://docs.kubernetes.org.cn/626.html)
[root@k8s-master1 ~]#

访问地址：http://NodeIP:Port

七、扩容多Master（高可用架构）

  Kubernetes作为容器集群系统，通过健康检查+重启策略实现了Pod故障自我修复能力，通过调度算法实现将Pod分布式部署，并保持预期副本数，根据Node失效状态自动在其他Node拉起Pod，实现了应用层的高可用性。
  针对Kubernetes集群，高可用性还应包含以下两个层面的考虑：Etcd数据库的高可用性和Kubernetes Master组件的高可用性。 而Etcd我们已经采用3个节点组建集群实现高可用，本节将对Master节点高可用进行说明和实施。
  Master节点扮演着总控中心的角色，通过不断与工作节点上的Kubelet和kube-proxy进行通信来维护整个集群的健康工作状态。如果Master节点故障，将无法使用kubectl工具或者API做任何集群管理。
  Master节点主要有三个服务kube-apiserver、kube-controller-manager和kube-scheduler，其中kube-controller-manager和kube-scheduler组件自身通过选择机制已经实现了高可用，所以Master高可用主要针对kube-apiserver组件，而该组件是以HTTP API提供服务，因此对他高可用与Web服务器类似，增加负载均衡器对其负载均衡即可，并且可水平扩容。

多Master架构图：
在这里插入图片描述

7.1 部署Master2 Node

  现在需要再增加一台新服务器，作为Master2 Node，IP是192.168.100.64。
  为了节省资源你也可以将之前部署好的Worker Node1复用为Master2 Node角色（即部署Master组件）
  Master2 与已部署的Master1所有操作一致。所以我们只需将Master1所有K8s文件拷贝过来，再修改下服务器IP和主机名启动即可。

1. 安装Docker

scp /usr/bin/docker* root@192.168.100.64:/usr/bin
scp /usr/bin/runc root@192.168.100.64:/usr/bin
scp /usr/bin/containerd* root@192.168.100.64:/usr/bin
scp /usr/lib/systemd/system/docker.service root@192.168.100.64:/usr/lib/systemd/system
scp -r /etc/docker root@192.168.100.64:/etc

# 在Master2启动Docker
systemctl daemon-reload
systemctl start docker
systemctl enable docker

2. 创建etcd证书目录

在Master2创建etcd证书目录：

mkdir -p /opt/etcd/ssl

3. 拷贝文件（Master1操作）

拷贝Master1上所有K8s文件和etcd证书到Master2：

scp -r /opt/kubernetes root@192.168.100.64:/opt
scp -r /opt/etcd/ssl root@192.168.100.64:/opt/etcd
scp /usr/lib/systemd/system/kube* root@192.168.100.64:/usr/lib/systemd/system
scp /usr/bin/kubectl  root@192.168.100.64:/usr/bin
scp -r ~/.kube root@192.168.100.64:~

4. 删除证书文件

删除kubelet证书和kubeconfig文件：

rm -f /opt/kubernetes/cfg/kubelet.kubeconfig 
rm -f /opt/kubernetes/ssl/kubelet*

5. 修改配置文件IP和主机名

修改apiserver、kubelet和kube-proxy配置文件为本地IP：

vi /opt/kubernetes/cfg/kube-apiserver.conf 
...
--bind-address=192.168.100.64 \
--advertise-address=192.168.100.64 \
...

vi /opt/kubernetes/cfg/kube-controller-manager.kubeconfig
server: https://192.168.100.64:6443

vi /opt/kubernetes/cfg/kube-scheduler.kubeconfig
server: https://192.168.100.64:6443

vi /opt/kubernetes/cfg/kubelet.conf
--hostname-override=k8s-master2

vi /opt/kubernetes/cfg/kube-proxy-config.yml
hostnameOverride: k8s-master2

vi ~/.kube/config
...
server: https://192.168.100.64:6443

6. 启动设置开机启动

systemctl daemon-reload
systemctl start kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy
systemctl enable kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy

7. 查看集群状态

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

8. 批准kubelet证书申请

# 查看证书请求
kubectl get csr
NAME                      AGE          SIGNERNAME          REQUESTOR           CONDITION
node-csr-JYNknakEa_YpHz797oKaN-ZTk43nD51Zc9CJkBLcASU   85m   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending
# 授权请求
kubectl certificate approve node-csr-JYNknakEa_YpHz797oKaN-ZTk43nD51Zc9CJkBLcASU

# 查看Node
kubectl get node
NAME        STATUS   ROLES    AGE   VERSION
k8s-master1    Ready    <none>   34h   v1.20.4
k8s-master2    Ready    <none>   2m   v1.20.4
k8s-node1     Ready    <none>   33h   v1.20.4
k8s-node2     Ready    <none>   33h   v1.20.4

如果你在学习中遇到问题或者文档有误可联系阿良~ 微信: k8init

7.2 部署Nginx+Keepalived高可用负载均衡器

kube-apiserver高可用架构图：
在这里插入图片描述

ginx是一个主流Web服务和反向代理服务器，这里用四层实现对apiserver实现负载均衡。
Keepalived是一个主流高可用软件，基于VIP绑定实现服务器双机热备，在上述拓扑中，Keepalived主要根据Nginx运行状态判断是否需要故障转移（漂移VIP），例如当Nginx主节点挂掉，VIP会自动绑定在Nginx备节点，从而保证VIP一直可用，实现Nginx高可用。

注1：为了节省机器，这里与K8s Master节点机器复用。也可以独立于k8s集群之外部署，只要nginx与apiserver能通信就行。
注2：如果你是在公有云上，一般都不支持keepalived，那么你可以直接用它们的负载均衡器产品，直接负载均衡多台Master kube-apiserver，架构与上面一样。
在两台Master节点操作。

1. 安装软件包（主/备）

yum install epel-release -y
yum install nginx keepalived -y

2. Nginx配置文件（主/备一样）

cat > /etc/nginx/nginx.conf << "EOF"
user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;

include /usr/share/nginx/modules/*.conf;

events {
    worker_connections 1024;
}

# 四层负载均衡，为两台Master apiserver组件提供负载均衡
stream {

    log_format  main  '$remote_addr $upstream_addr - [$time_local] $status $upstream_bytes_sent';

    access_log  /var/log/nginx/k8s-access.log  main;

    upstream k8s-apiserver {
       server 192.168.100.61:6443;   # Master1 APISERVER IP:PORT
       server 192.168.100.64:6443;   # Master2 APISERVER IP:PORT
    }
    
    server {
       listen 16443; # 由于nginx与master节点复用，这个监听端口不能是6443，否则会冲突
       proxy_pass k8s-apiserver;
    }
}

http {
    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

    sendfile            on;
    tcp_nopush          on;
    tcp_nodelay         on;
    keepalive_timeout   65;
    types_hash_max_size 2048;

    include             /etc/nginx/mime.types;
    default_type        application/octet-stream;

    server {
        listen       80 default_server;
        server_name  _;

        location / {
        }
    }
}
EOF

3. keepalived配置文件（Nginx Master）

cat > /etc/keepalived/keepalived.conf << EOF
global_defs { 
   notification_email { 
     acassen@firewall.loc 
     failover@firewall.loc 
     sysadmin@firewall.loc 
   } 
   notification_email_from Alexandre.Cassen@firewall.loc  
   smtp_server 127.0.0.1 
   smtp_connect_timeout 30 
   router_id NGINX_MASTER
} 

vrrp_script check_nginx {
    script "/etc/keepalived/check_nginx.sh"
}

vrrp_instance VI_1 { 
    state MASTER 
    interface ens33  # 修改为实际网卡名
    virtual_router_id 51 # VRRP 路由 ID实例，每个实例是唯一的 
    priority 100    # 优先级，备服务器设置 90 
    advert_int 1    # 指定VRRP 心跳包通告间隔时间，默认1秒 
    authentication { 
        auth_type PASS      
        auth_pass 1111 
    }  
    # 虚拟IP
    virtual_ipaddress { 
        192.168.100.65/24
    } 
    track_script {
        check_nginx
    } 
}
EOF

vrrp_script：指定检查nginx工作状态脚本（根据nginx状态判断是否故障转移）
virtual_ipaddress：虚拟IP（VIP）
准备上述配置文件中检查nginx运行状态的脚本：

cat > /etc/keepalived/check_nginx.sh  << "EOF"
#!/bin/bash
count=$(ss -antp |grep 16443 |egrep -cv "grep|$$")

if [ "$count" -eq 0 ];then
    exit 1
else
    exit 0
fi
EOF
chmod +x /etc/keepalived/check_nginx.sh
4. keepalived配置文件（Nginx Backup）
cat > /etc/keepalived/keepalived.conf << EOF
global_defs { 
   notification_email { 
     acassen@firewall.loc 
     failover@firewall.loc 
     sysadmin@firewall.loc 
   } 
   notification_email_from Alexandre.Cassen@firewall.loc  
   smtp_server 127.0.0.1 
   smtp_connect_timeout 30 
   router_id NGINX_BACKUP
} 

vrrp_script check_nginx {
    script "/etc/keepalived/check_nginx.sh"
}

vrrp_instance VI_1 { 
    state BACKUP 
    interface ens33
    virtual_router_id 51 # VRRP 路由 ID实例，每个实例是唯一的 
    priority 90
    advert_int 1
    authentication { 
        auth_type PASS      
        auth_pass 1111 
    }  
    virtual_ipaddress { 
        192.168.100.65/24
    } 
    track_script {
        check_nginx
    } 
}
EOF

准备上述配置文件中检查nginx运行状态的脚本：

cat > /etc/keepalived/check_nginx.sh  << "EOF"
#!/bin/bash
count=$(ss -antp |grep 16443 |egrep -cv "grep|$$")

if [ "$count" -eq 0 ];then
    exit 1
else
    exit 0
fi
EOF
chmod +x /etc/keepalived/check_nginx.sh

注：keepalived根据脚本返回状态码（0为工作正常，非0不正常）判断是否故障转移。

5. 启动并设置开机启动

systemctl daemon-reload
systemctl start nginx keepalived
systemctl enable nginx keepalived

6. 查看keepalived工作状态

ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:04:f7:2c brd ff:ff:ff:ff:ff:ff
    inet 192.168.31.80/24 brd 192.168.31.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet 192.168.100.65/24 scope global secondary ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe04:f72c/64 scope link 
       valid_lft forever preferred_lft forever

可以看到，在ens33网卡绑定了192.168.100.65 虚拟IP，说明工作正常。

7. Nginx+Keepalived高可用测试

关闭主节点Nginx，测试VIP是否漂移到备节点服务器。
在Nginx Master执行 pkill nginx;
在Nginx Backup，ip addr命令查看已成功绑定VIP。

8. 访问负载均衡器测试

找K8s集群中任意一个节点，使用curl查看K8s版本测试，使用VIP访问：

curl -k https://192.168.100.65:16443/version
{
  "major": "1",
  "minor": "20",
  "gitVersion": "v1.20.4",
  "gitCommit": "e87da0bd6e03ec3fea7933c4b5263d151aafd07c",
  "gitTreeState": "clean",
  "buildDate": "2021-02-18T16:03:00Z",
  "goVersion": "go1.15.8",
  "compiler": "gc",
  "platform": "linux/amd64"
}

可以正确获取到K8s版本信息，说明负载均衡器搭建正常。该请求数据流程：curl -> vip(nginx) -> apiserver
通过查看Nginx日志也可以看到转发apiserver IP：

tail /var/log/nginx/k8s-access.log -f
192.168.100.61 192.168.100.61:6443 - [02/Apr/2021:19:17:57 +0800] 200 423
192.168.100.61 192.168.100.62:6443 - [02/Apr/2021:19:18:50 +0800] 200 423

到此还没结束，还有下面最关键的一步。

7.3 修改所有Worker Node连接LB VIP

  试想下，虽然我们增加了Master2 Node和负载均衡器，但是我们是从单Master架构扩容的，也就是说目前所有的Worker Node组件连接都还是Master1 Node，如果不改为连接VIP走负载均衡器，那么Master还是单点故障。
  因此接下来就是要改所有Worker Node（kubectl get node命令查看到的节点）组件配置文件，由原来192.168.100.61修改为192.168.100.65（VIP）。
在所有Worker Node执行：

sed -i 's#192.168.100.61:6443#192.168.100.65:16443#' /opt/kubernetes/cfg/*
systemctl restart kubelet kube-proxy

检查节点状态：

kubectl get node 
NAME         STATUS   ROLES    AGE   VERSION 
k8s-master1   Ready    <none>   32d   v1.20.4 
k8s-master2   Ready    <none>   10m   v1.20.4 
k8s-node1    Ready    <none>   31d   v1.20.4 
k8s-node2    Ready    <none>   31d   v1.20.4

至此，一套完整的 Kubernetes 高可用集群就部署完成了！

f7:2c brd ff:ff:ff:ff:ff:ff
inet 192.168.31.80/24 brd 192.168.31.255 scope global noprefixroute ens33
valid_lft forever preferred_lft forever
inet 192.168.100.65/24 scope global secondary ens33
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe04:f72c/64 scope link
valid_lft forever preferred_lft forever

可以看到，在ens33网卡绑定了192.168.100.65 虚拟IP，说明工作正常。

### 7. Nginx+Keepalived高可用测试
关闭主节点Nginx，测试VIP是否漂移到备节点服务器。  
在Nginx Master执行 pkill nginx;  
在Nginx Backup，ip addr命令查看已成功绑定VIP。  
### 8. 访问负载均衡器测试
找K8s集群中任意一个节点，使用curl查看K8s版本测试，使用VIP访问：

curl -k https://192.168.100.65:16443/version
{
“major”: “1”,
“minor”: “20”,
“gitVersion”: “v1.20.4”,
“gitCommit”: “e87da0bd6e03ec3fea7933c4b5263d151aafd07c”,
“gitTreeState”: “clean”,
“buildDate”: “2021-02-18T16:03:00Z”,
“goVersion”: “go1.15.8”,
“compiler”: “gc”,
“platform”: “linux/amd64”
}

可以正确获取到K8s版本信息，说明负载均衡器搭建正常。该请求数据流程：curl -> vip(nginx) -> apiserver  
通过查看Nginx日志也可以看到转发apiserver IP：

tail /var/log/nginx/k8s-access.log -f
192.168.100.61 192.168.100.61:6443 - [02/Apr/2021:19:17:57 +0800] 200 423
192.168.100.61 192.168.100.62:6443 - [02/Apr/2021:19:18:50 +0800] 200 423

到此还没结束，还有下面最关键的一步。
## 7.3 修改所有Worker Node连接LB VIP
&emsp;&emsp;试想下，虽然我们增加了Master2 Node和负载均衡器，但是我们是从单Master架构扩容的，也就是说目前所有的Worker Node组件连接都还是Master1 Node，如果不改为连接VIP走负载均衡器，那么Master还是单点故障。    
&emsp;&emsp;因此接下来就是要改所有Worker Node（kubectl get node命令查看到的节点）组件配置文件，由原来192.168.100.61修改为192.168.100.65（VIP）。  
在所有Worker Node执行：

sed -i ‘s#192.168.100.61:6443#192.168.100.65:16443#’ /opt/kubernetes/cfg/*
systemctl restart kubelet kube-proxy

检查节点状态：

kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready 32d v1.20.4
k8s-master2 Ready 10m v1.20.4
k8s-node1 Ready 31d v1.20.4
k8s-node2 Ready 31d v1.20.4

至此，一套完整的 Kubernetes 高可用集群就部署完成了！
# kubernetes # docker # 容器
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【深度】阿里巴巴万级规模 K8s 集群全局高可用体系之美

作者 |  韩堂、柘远、沉醉来源 | 阿里巴巴云原生公众号​前言台湾作家林清玄在接受记者采访的时候，如此评价自己 30 多年写作生涯：“第一个十年我才华横溢，‘贼光闪现’，令周边黯然失色；第二个十年，我终于‘宝光现形’，不再去抢风头，反而与身边的美丽相得益彰；进入第三个十年，繁华落尽见真醇，我进入了‘醇光初现’的阶段，真正体味到了境界之美”。​长夜有穷，真水无香。领略过了 K8s“身在江

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如何基于 K8s 构建下一代 DevOps 平台？

作者 | 孙健波（天元）导读：当前云原生 DevOps 体系现状如何？面临哪些挑战？如何通过 OAM 解决云原生 DevOps 场景下的诸多问题？云原生开发应用模型 OAM(Open Application Model) 社区核心成员孙健波将为大家一一解答，并分享如何基于 OAM 和 Kubernetes 打造无限能力的下一代 DevOps 平台。什么是 DevOps？为什么基于 Kub

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k8s 火了！

2020，上云之年，产品云端化成为一种趋势。在一线城市，很多公司都已经构建了自己的私有云环境，比如阿里云、网易云、华为云等。而Kubernetes 作为基于容器编排领域的王者，具备扩展...

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