二进制部署k8s集群

部署k8s有多种方式,本章我们采取二进制的部署方式来部署k8s集群,二进制部署麻烦点，但是可以在我们通过部署各个组件的时候，也通知能让我们更好的深入了解组件之间的关联,也利于后期维护

主机环境

• 系统: centos7.5 3台
• 内存: 4G
• 磁盘:40G
• cpu 2CPU

软件版本

• k8s 1.18
• docker 19-ce

主机规划

master	172.25.120.17	kube-apiserver，kube-controller-manager，kube-scheduler，etcd
node-1	172.25.120.18	kubelet，kube-proxy，docker etcd
node-2	172.25.120.19	kubelet，kube-proxy，docker etcd

 

 

1.主机环境初始化

在3个节点上操作

#更改主机名
hostnamectl set-hostname master

hostnamectl set-hostname node-1

hostnamectl set-hostname node-2

#关闭防火墙
systemctl stop firewalld ; systemctl disable firewalld
#关闭selinux
setenforce 0 ;sed -i 's/enforcing/disabled/' /etc/selinux/config
#关闭swap分区
swapoff -a ; sed -ri 's/.*swap.*/#&/' /etc/fstab
#添加hosts
cat >> /etc/hosts << EOF
172.25.120.17 master k8s-master
172.25.120.18 node-1 k8s-node1
172.25.120.19 node-2 k8s-node2
EOF
#添加防火墙转发
cat > /etc/sysctl.d/k8s.conf << EOF
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
modprobe br_netfilter
sysctl --system ##生效
#时间同步
yum install -y ntpdate  ##安装时间同步工具
ntpdate time.windows.com  #同步windwos时间服务器

#磁盘分区，建议由数据盘的首先给/var/lib/docker做个lvm分区

在master节点操作

#生成秘钥对
ssh-keygen -t rsa

#将公钥拷贝至每台主机
ssh-copy-id root@master
ssh-copy-id root@node-1
ssh-copy-id root@node-2

 

2.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

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

在master上操作:

##获取证书管理工具
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
##添加看执行权限并放进可执行目录
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/bin/cfssl-certinfo

2.2生成Etcd证书(etcd单独构建CA)

创建证书目录

mkdir -p ~/TLS/{etcd,k8s}
cd ~/TLS/etcd  ##进入证书目录

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：

cfssl gencert -initca ca-csr.json | cfssljson -bare ca -
ls *pem ##可以看到当前目录生成了两个证书文件
ca-key.pem  ca.pem

2. 使用自签CA签发Etcd HTTPS证书(这里etcd peer，client，server使用同一套证书）

创建证书申请文件：

cat > server-csr.json << EOF
{
    "CN": "etcd",
    "hosts": [
    "172.25.120.17",
    "172.25.120.18",
    "172.25.120.19"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "BeiJing",
            "ST": "BeiJing"
        }
    ]
}
EOF

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
ls server*pem  ##可以看到生成了两个sever证书
server-key.pem  server.pem

2.3下载etcd二进制文件

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

以下操作在master上操作,待会将master生成的所有文件拷贝到node-1和node-2:

wget https://github.com/etcd-io/etcd/releases/download/v3.4.9/etcd-v3.4.9-linux-amd64.tar.gz ##获取二进制文件

2.4部署etcd集群

1.创建工作目录并解压二进制文件

mkdir /home/k8s/etcd/{bin,cfg,ssl} -p
tar zxvf etcd-v3.4.9-linux-amd64.tar.gz
mv etcd-v3.4.9-linux-amd64/{etcd,etcdctl} /home/k8s/etcd/bin/

2.创建etcd配置文件

cat > /home/k8s/etcd/cfg/etcd.conf << EOF
#[Member]
ETCD_NAME="etcd-1"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://172.25.120.17:2380"
ETCD_LISTEN_CLIENT_URLS="https://172.25.120.17:2379"
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://172.25.120.17:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://172.25.120.17:2379"
ETCD_INITIAL_CLUSTER="etcd-1=https://172.25.129.17:2380,etcd-2=https://172.25.120.18:2380,etcd-3=https://172.25.120.19:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
EOF

参数详解:

• 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_PEER_URLS：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_INITIAL_CLUSTER_TOKEN：集群Token
• ETCD_INITIAL_CLUSTER_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.配置systemd管理etcd

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=/home/k8s/etcd/cfg/etcd.conf
ExecStart=/home/k8s/etcd/bin/etcd \
--cert-file=/home/k8s/etcd/ssl/server.pem \
--key-file=/home/k8s/etcd/ssl/server-key.pem \
--peer-cert-file=/home/k8s/etcd/ssl/server.pem \
--peer-key-file=/home/k8s/etcd/ssl/server-key.pem \
--trusted-ca-file=/home/k8s/etcd/ssl/ca.pem \
--peer-trusted-ca-file=/home/k8s/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：

cp ~/TLS/etcd/ca*pem ~/TLS/etcd/server*pem /home/k8s/etcd/ssl/

5.将master生成的所有文件拷贝到其他节点

scp -r /home/k8s/etcd/ node-1:/home/k8s/
scp /usr/lib/systemd/system/etcd.service node-1:/usr/lib/systemd/system/
scp -r /home/k8s/etcd/ node-2:/home/k8s/
scp /usr/lib/systemd/system/etcd.service node-2:/usr/lib/systemd/system/

6.在node-1和node-2分别修改etcd.conf配置文件中的节点名称和当前服务器IP

sed -i '4,8s/172.25.120.17/172.25.120.18/' /home/k8s/etcd/cfg/etcd.conf  ; sed -i '2s/etcd-1/etcd-2/'  /home/k8s/etcd/cfg/etcd.conf ###在node1执行
sed -i '4,8s/172.25.120.17/172.25.120.19/' /home/k8s/etcd/cfg/etcd.conf  ; sed -i '2s/etcd-1/etcd-3/'  /home/k8s/etcd/cfg/etcd.conf ###在node2执行

7.启动3个节点的etcd并加入开机自启

在三各节点操作

systemctl daemon-reload
systemctl start etcd
systemctl enable etcd

8.查看etcd集群状态

[root@master ~]# ETCDCTL_API=3 /home/k8s/etcd/bin/etcdctl --cacert=/home/k8s/etcd/ssl/ca.pem --cert=/home/k8s/etcd/ssl/server.pem --key=/home/k8s/etcd/ssl/server-key.pem --endpoints="https://172.25.120.17:2379,https://172.25.120.18:2379,https://172.25.120.19:2379" endpoint health
https://172.25.120.18:2379 is healthy: successfully committed proposal: took = 14.194738ms
https://172.25.120.19:2379 is healthy: successfully committed proposal: took = 14.97292ms
https://172.25.120.17:2379 is healthy: successfully committed proposal: took = 14.847968ms

出现successfully,表面etcd部署成功,如果有异常情况可以使用systemctl stautus etcd -l进一步查看报错信息

3.安装Docker

可以使用yum安装,这次我们采用二进制的方式

以下所有操作在所有节点

3.1获取docker安装包

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

3.2解压docker二进制包

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

3.3配置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

3.4配置docker加速器

mkdir /etc/docker
cat > /etc/docker/daemon.json << EOF
 {
"registry-mirrors": ["https://jo6348gu.mirror.aliyuncs.com"]
 }
EOF

3.5启动docker并加入开机自启

systemctl daemon-reload
systemctl start docker
systemctl enable docker

4.部署master

以下操作在master上

4.1 生成kube-apiserver证书(这里再自建一个CA，没有服用前面的etcd ca)

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 -
ls *pem
ca-key.pem  ca.pem  ##可以看到生成了两个证书

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
# hosts: 表示访问api-server 的各个方式，所以需要对每个访问方式都要签证，比如10.0.0.1 是api-server的svc地址
{
    "CN": "kubernetes",
    "hosts": [
      "10.0.0.1",
      "127.0.0.1",
      "172.25.120.17",
      "172.25.120.18",
      "172.25.120.19",
      "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

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
ls server*pem
server-key.pem  server.pem ##可以看到又生成两个server证书

4.2 从Github下载k8s二进制文件并解压

1.获取二进制包

wget  https://dl.k8s.io/v1.18.3/kubernetes-server-linux-amd64.tar.gz

2.解压二进制包

mkdir -p /home/k8s/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 /home/k8s/kubernetes/bin
cp kubectl /usr/bin/

4.3部署kube-apiserver

1. 创建配置文件

cat > /home/k8s/kubernetes/cfg/kube-apiserver.conf << EOF
KUBE_APISERVER_OPTS="--logtostderr=false \\
--v=4 \\
--log-dir=/home/k8s/kubernetes/logs \\
--etcd-servers=https://172.25.120.17:2379,https://172.25.120.18:2379,https://172.25.120.19:2379 \\
--bind-address=172.25.120.17 \\
--secure-port=6443 \\
--advertise-address=172.25.120.17 \\
--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=/home/k8s/kubernetes/cfg/token.csv \\
--service-node-port-range=30000-32767 \\
--kubelet-client-certificate=/home/k8s/kubernetes/ssl/server.pem \\
--kubelet-client-key=/home/k8s/kubernetes/ssl/server-key.pem \\
--tls-cert-file=/home/k8s/kubernetes/ssl/server.pem  \\
--tls-private-key-file=/home/k8s/kubernetes/ssl/server-key.pem \\
--client-ca-file=/home/k8s/kubernetes/ssl/ca.pem \\
--service-account-key-file=/home/k8s/kubernetes/ssl/ca-key.pem \\
--etcd-cafile=/home/k8s/etcd/ssl/ca.pem \\
--etcd-certfile=/home/k8s/etcd/ssl/server.pem \\
--etcd-keyfile=/home/k8s/etcd/ssl/server-key.pem \\
--audit-log-maxage=30 \\
--audit-log-maxbackup=3 \\
--audit-log-maxsize=100 \\
--audit-log-path=/home/k8s/kubernetes/logs/k8s-audit.log"
EOF

• 参数详解:
• –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
• –etcd-xxxfile：连接Etcd集群证书
• –audit-log-xxx：审计日志

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 /home/k8s/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：

 

image.png

创建上述配置文件中token文件：

# 这里使用用户名，不要使用UID
cat > /home/k8s/kubernetes/cfg/token.csv << EOF
b1dc586d69159ff4e3ef7efa9db60e48,kubelet-bootstrap,"system:node-bootstrapper"
EOF

格式：token，用户名，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=/home/k8s/kubernetes/cfg/kube-apiserver.conf
ExecStart=/home/k8s/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

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

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

4.4 部署kube-controller-manager

1. 创建配置文件

cat > /home/k8s/kubernetes/cfg/kube-controller-manager.conf << EOF
KUBE_CONTROLLER_MANAGER_OPTS="--logtostderr=false \\
--v=4 \\
--log-dir=/home/k8s/kubernetes/logs \\
--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=/home/k8s/kubernetes/ssl/ca.pem \\
--cluster-signing-key-file=/home/k8s/kubernetes/ssl/ca-key.pem  \\
--root-ca-file=/home/k8s/kubernetes/ssl/ca.pem \\
--service-account-private-key-file=/home/k8s/kubernetes/ssl/ca-key.pem \\
--experimental-cluster-signing-duration=87600h0m0s"
EOF

• –master：通过本地非安全本地端口8080连接apiserver。
• –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. 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=/home/k8s/kubernetes/cfg/kube-controller-manager.conf
ExecStart=/home/k8s/kubernetes/bin/kube-controller-manager \$KUBE_CONTROLLER_MANAGER_OPTS
Restart=on-failure
[Install]
WantedBy=multi-user.target
EOF

3.启动并设置开机启动

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

4.6 部署kube-scheduler

1. 创建配置文件

cat > /home/k8s/kubernetes/cfg/kube-scheduler.conf << EOF
KUBE_SCHEDULER_OPTS="--logtostderr=false \
--v=2 \
--log-dir=/home/k8s/kubernetes/logs \
--leader-elect \
--master=127.0.0.1:8080 \
--bind-address=127.0.0.1"
EOF

• –master：通过本地非安全本地端口8080连接apiserver。
• –leader-elect：当该组件启动多个时，自动选举（HA）

2. 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=/home/k8s/kubernetes/cfg/kube-scheduler.conf
ExecStart=/home/k8s/kubernetes/bin/kube-scheduler \$KUBE_SCHEDULER_OPTS
Restart=on-failure
[Install]
WantedBy=multi-user.target
EOF

3.启动并设置开机启动

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

4. 查看集群状态

所有组件都已经启动成功，通过kubectl get cs命令查看当前集群组件状态：

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

五、部署Worker Node

下面还是在master节点上操作，即同时作为Worker Node

5.1 拷贝二进制文件

cd ~/kubernetes/server/bin
cp kubelet kube-proxy /home/k8s/kubernetes/bin

5.2 部署kubelet

1. 创建配置文件

cat > /home/k8s/kubernetes/cfg/kubelet.conf << EOF
KUBELET_OPTS="--logtostderr=false \\
--v=4 \\
--log-dir=/home/k8s/kubernetes/logs \\
--hostname-override=k8s-master \\
--network-plugin=cni \\
--kubeconfig=/home/k8s/kubernetes/cfg/kubelet.kubeconfig \\
--bootstrap-kubeconfig=/home/k8s/kubernetes/cfg/bootstrap.kubeconfig \\
--config=/home/k8s/kubernetes/cfg/kubelet-config.yml \\
--cert-dir=/home/k8s/kubernetes/ssl \\
--pod-infra-container-image=lizhenliang/pause-amd64:3.0"
EOF

参数详解:

• –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. 创建配置参数yaml文件

cat > /home/k8s/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: /home/k8s/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bootstrap.kubeconfig文件

##设置环境变量
KUBE_APISERVER="https://172.25.120.17:6443" # apiserver IP:PORT
TOKEN="b1dc586d69159ff4e3ef7efa9db60e48" # 与token.csv里保持一致

# 生成 kubelet bootstrap kubeconfig 配置文件
kubectl config set-cluster kubernetes \
  --certificate-authority=/home/k8s/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=bootstrap.kubeconfig
kubectl config set-credentials "kubelet-bootstrap" \
  --token=${TOKEN} \
  --kubeconfig=bootstrap.kubeconfig
kubectl config set-context default \
  --cluster=kubernetes \
  --user="kubelet-bootstrap" \
  --kubeconfig=bootstrap.kubeconfig
kubectl config use-context default --kubeconfig=bootstrap.kubeconfig

拷贝到配置文件路径：

cp bootstrap.kubeconfig /home/k8s/kubernetes/cfg

4. systemd管理kubelet

cat > /usr/lib/systemd/system/kubelet.service << EOF
[Unit]
Description=Kubernetes Kubelet
After=docker.service
[Service]
EnvironmentFile=/home/k8s/kubernetes/cfg/kubelet.conf
ExecStart=/home/k8s/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

systemctl daemon-reload
systemctl start kubelet
systemctl enable kubelet

5.3 批准kubelet证书申请并加入集群

# 查看kubelet证书请求
kubectl get csr
NAME                                                   AGE   SIGNERNAME                                    REQUESTOR           CONDITION
node-csr-d-UyqVObT-tnWdXd881Ppc3oNVr6xkCBXV7VRlWyhf8   30s   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending
# 批准申请
kubectl certificate approve node-csr-d-UyqVObT-tnWdXd881Ppc3oNVr6xkCBXV7VRlWyhf8
# 查看节点
kubectl get node
NAME         STATUS     ROLES    AGE   VERSION
k8s-master   NotReady   <none>   15s   v1.18.3  ##由于没有部署网络插件,所以节点是NotReady

5.4 部署kube-proxy

1. 创建配置文件

cat > /home/k8s/kubernetes/cfg/kube-proxy.conf << EOF
KUBE_PROXY_OPTS="--logtostderr=false \\
--v=4 \\
--log-dir=/home/k8s/kubernetes/logs \\
--config=/home/k8s/kubernetes/cfg/kube-proxy-config.yml"
EOF

2. 配置参数文件

cat > /home/k8s/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: /home/k8s/kubernetes/cfg/kube-proxy.kubeconfig
hostnameOverride: k8s-master
clusterCIDR: 10.0.0.0/24
EOF

3. 生成kube-proxy.kubeconfig文件

生成kube-proxy证书：

# 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

ls kube-proxy*pem
kube-proxy-key.pem  kube-proxy.pem  ##可以看到生成了两个kube-proxy的证书文件

生成kubeconfig文件

#创建环境变量
KUBE_APISERVER="https://172.25.120.17:6443"

kubectl config set-cluster kubernetes \
  --certificate-authority=/home/k8s/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=kube-proxy.kubeconfig
kubectl config set-credentials kube-proxy \
  --client-certificate=./kube-proxy.pem \
  --client-key=./kube-proxy-key.pem \
  --embed-certs=true \
  --kubeconfig=kube-proxy.kubeconfig
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kube-proxy \
  --kubeconfig=kube-proxy.kubeconfig
kubectl config use-context default --kubeconfig=kube-proxy.kubeconfig

拷贝到配置文件指定路径：

cp kube-proxy.kubeconfig /home/k8s/kubernetes/cfg/

4. systemd管理kube-proxy

cat > /usr/lib/systemd/system/kube-proxy.service << EOF
[Unit]
Description=Kubernetes Proxy
After=network.target
[Service]
EnvironmentFile=/home/k8s/kubernetes/cfg/kube-proxy.conf
ExecStart=/home/k8s/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

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

5.5 部署CNI网络

1.先下载CNI二进制文件：

wget https://github.com/containernetworking/plugins/releases/download/v0.8.6/cni-plugins-linux-amd64-v0.8.6.tgz

2.解压二进制包并移动到默认工作目录

mkdir -p /opt/cni/bin
tar zxvf cni-plugins-linux-amd64-v0.8.6.tgz -C /opt/cni/bin

5.5部署CNI网络

获取flanel网络yaml文件,并修改镜像地址

echo "151.101.76.133 raw.githubusercontent.com" >>/etc/hosts
wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
sed -i -r "s#quay.io/coreos/flannel:.*-amd64#lizhenliang/flannel:v0.12.0-amd64#g" kube-flannel.yml  ##默认镜像地址无法访问，修改为docker hub镜像仓库。

开始部署CNI网络：

kubectl apply -f kube-flannel.yml
##查看pod是否运行成功
kubectl get pods -n kube-system
NAME                          READY   STATUS    RESTARTS   AGE
kube-flannel-ds-amd64-p9tdp   1/1     Running   0
##运行成功后,再查看节点是否运行正常
kubectl get nodes
NAME         STATUS   ROLES    AGE   VERSION
k8s-master   Ready    <none>   19m   v1.18.3

5.6 授权apiserver访问kubelet

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

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

5.7增加worker 节点

1. 拷贝已部署好的Node相关文件到新节点

在master节点将Worker Node涉及文件拷贝到节点172.16.210..54/55

scp -r /home/k8s/kubernetes root@172.25.120.18:/home/k8s/
scp -r /usr/lib/systemd/system/{kubelet,kube-proxy}.service root@172.25.120.18:/usr/lib/systemd/system
scp -r /home/k8s/cni/ root@172.25.120.18:/home/k8s/
scp /home/k8s/kubernetes/ssl/ca.pem root@172.25.120.18:/home/k8s/kubernetes/ssl

2. 在node节点删除kubelet证书和kubeconfig文件

rm -f /home/k8s/kubernetes/cfg/kubelet.kubeconfig
rm -f /home/k8s/kubernetes/ssl/kubelet*

3. 修改主机名

sed -i 's/k8s-master/node-1/g' /home/k8s/kubernetes/cfg/kubelet.conf /home/k8s/kubernetes/cfg/kube-proxy-config.yml   ##加入node2的主机只需要把这条命令的k8s-node1改成k8s-node2即可

4. 启动并设置开机启动

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

5.在Master上批准新Node kubelet证书申请

kubectl get csr
NAME                                                   AGE   SIGNERNAME                                    REQUESTOR           CONDITION
node-csr--t2cjSYX0z7ba4Tyh4GCnngZaGBUwmAHyY1xuxU40j0   28s   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending

kubectl certificate approve node-csr--t2cjSYX0z7ba4Tyh4GCnngZaGBUwmAHyY1xuxU40j0

6. 查看Node状态

kubectl get nodes
NAME         STATUS   ROLES    AGE     VERSION
k8s-master   Ready    <none>   46m     v1.18.3
k8s-node1    Ready    <none>   8m57s   v1.18.3
k8s-node2    Ready    <none>   3m59s   v1.18.3

Node2（172.25.120.19 ）节点同上。记得修改主机名

六、部署Dashboard和CoreDNS

Dashboard的部署可以看我另一篇文档,这里就不部署了

https://www.jianshu.com/p/6bafe568f103

部署CoreDNS

CoreDNS用于集群内部Service名称解析

# Warning: This is a file generated from the base underscore template file: coredns.yaml.base

apiVersion: v1
kind: ServiceAccount
metadata:
  name: coredns
  namespace: kube-system
  labels:
      kubernetes.io/cluster-service: "true"
      addonmanager.kubernetes.io/mode: Reconcile
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
    addonmanager.kubernetes.io/mode: Reconcile
  name: system:coredns
rules:
- apiGroups:
  - ""
  resources:
  - endpoints
  - services
  - pods
  - namespaces
  verbs:
  - list
  - watch
- apiGroups:
  - ""
  resources:
  - nodes
  verbs:
  - get
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  annotations:
    rbac.authorization.kubernetes.io/autoupdate: "true"
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
    addonmanager.kubernetes.io/mode: EnsureExists
  name: system:coredns
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:coredns
subjects:
- kind: ServiceAccount
  name: coredns
  namespace: kube-system
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: coredns
  namespace: kube-system
  labels:
      addonmanager.kubernetes.io/mode: EnsureExists
data:
  Corefile: |
    .:53 {
        log
        errors
        health {
            lameduck 5s
        }
        ready
        kubernetes cluster.local in-addr.arpa ip6.arpa {
            pods insecure
            fallthrough in-addr.arpa ip6.arpa
            ttl 30
        }
        prometheus :9153
        forward . /etc/resolv.conf
        cache 30
        loop
        reload
        loadbalance
    }
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: coredns
  namespace: kube-system
  labels:
    k8s-app: kube-dns
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
    kubernetes.io/name: "CoreDNS"
spec:
  # replicas: not specified here:
  # 1. In order to make Addon Manager do not reconcile this replicas parameter.
  # 2. Default is 1.
  # 3. Will be tuned in real time if DNS horizontal auto-scaling is turned on.
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxUnavailable: 1
  selector:
    matchLabels:
      k8s-app: kube-dns
  template:
    metadata:
      labels:
        k8s-app: kube-dns
      annotations:
        seccomp.security.alpha.kubernetes.io/pod: 'runtime/default'
    spec:
      priorityClassName: system-cluster-critical
      serviceAccountName: coredns
      tolerations:
        - key: "CriticalAddonsOnly"
          operator: "Exists"
      nodeSelector:
        kubernetes.io/os: linux
      containers:
      - name: coredns
        image: lizhenliang/coredns:1.6.7
        imagePullPolicy: IfNotPresent
        resources:
          limits:
            memory: 512Mi
          requests:
            cpu: 100m
            memory: 70Mi
        args: [ "-conf", "/etc/coredns/Corefile" ]
        volumeMounts:
        - name: config-volume
          mountPath: /etc/coredns
          readOnly: true
        ports:
        - containerPort: 53
          name: dns
          protocol: UDP
        - containerPort: 53
          name: dns-tcp
          protocol: TCP
        - containerPort: 9153
          name: metrics
          protocol: TCP
        livenessProbe:
          httpGet:
            path: /health
            port: 8080
            scheme: HTTP
          initialDelaySeconds: 60
          timeoutSeconds: 5
          successThreshold: 1
          failureThreshold: 5
        readinessProbe:
          httpGet:
            path: /ready
            port: 8181
            scheme: HTTP
        securityContext:
          allowPrivilegeEscalation: false
          capabilities:
            add:
            - NET_BIND_SERVICE
            drop:
            - all
          readOnlyRootFilesystem: true
      dnsPolicy: Default
      volumes:
        - name: config-volume
          configMap:
            name: coredns
            items:
            - key: Corefile
              path: Corefile
---
apiVersion: v1
kind: Service
metadata:
  name: kube-dns
  namespace: kube-system
  annotations:
    prometheus.io/port: "9153"
    prometheus.io/scrape: "true"
  labels:
    k8s-app: kube-dns
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
    kubernetes.io/name: "CoreDNS"
spec:
  selector:
    k8s-app: kube-dns
  clusterIP: 10.0.0.2
  ports:
  - name: dns
    port: 53
    protocol: UDP
  - name: dns-tcp
    port: 53
    protocol: TCP
  - name: metrics
    port: 9153
    protocol: TCP

　　

kubectl apply -f coredns.yaml 

kubectl get pods -n kube-system ##查看coredns的pod是否运行正常
NAME                          READY   STATUS    RESTARTS   AGE
coredns-5ffbfd976d-rkcmt      1/1     Running   0          23s
kube-flannel-ds-amd64-2kmcm   1/1     Running   0          14m
kube-flannel-ds-amd64-p9tdp   1/1     Running   0          39m
kube-flannel-ds-amd64-zg7xz   1/1     Running   0          19m

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

能正常解析,说明没问题