一、部署前置知识点
1、生产环境可部署Kubernetes集群的两种方式
目前生产部署Kubernetes集群主要有两种方式:
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。官方地址:https://kubernetes.io/docs/reference/setup-tools/kubeadm/kubeadm/
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。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。
2、安装要求
在开始之前,部署Kubernetes集群机器需要满足以下几个条件:
一台或多台机器,操作系统 CentOS7.x-86_x64
硬件配置:2GB或更多RAM,2个CPU或更多CPU,硬盘30GB或更多
集群中所有机器之间网络互通
可以访问外网,需要拉取镜像,如果服务器不能上网,需要提前下载镜像并导入节点
禁止swap分区
3、准备环境
软件 | 版本 |
操作系统 | CentOS7.8_x64 (mini) |
Docker | 19-ce |
Kubernetes | 1.19 |
服务器整体规划:
角色 | IP | 组件 |
k8s-master1 | 192.168.31.71 | kube-apiserver,kube-controller-manager,kube-scheduler,etcd |
k8s-node1 | 192.168.31.72 | kubelet,kube-proxy,docker |
k8s-node2 | 192.168.31.73 | kubelet,kube-proxy,docker |
4、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
192.168.31.71 k8s-master
192.168.31.72 k8s-node1
192.168.31.73 k8s-node2
EOF
# 将桥接的IPv4流量传递到ipvs
yum install ipset ipvsadm -y
cat >> /etc/sysctl.conf << EOF
net.ipv4.ip_forward=1
EOF
#内核模块加载
cat > /etc/sysconfig/modules/ipvs.modules <<EOF
#!/bin/bash
ipvs_modules="ip_vs ip_vs_lc ip_vs_wlc ip_vs_rr ip_vs_wrr ip_vs_lblc ip_vs_lblcr ip_vs_dh ip_vs_sh ip_vs_fo ip_vs_nq ip_vs_sed ip_vs_ftp nf_conntrack_ipv4"
for kernel_module in \${ipvs_modules}; do
/sbin/modinfo -F filename \${kernel_module} > /dev/null 2>&1
if [ $? -eq 0 ]; then
/sbin/modprobe \${kernel_module}
fi
done
EOF
chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules && lsmod | grep ip_vs
sysctl -p # 生效
# 时间同步
yum install ntpdate -y
ntpdate time.windows.com
二、部署 Etcd
节点名称 | IP |
etcd | 192.168.31.71 |
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。
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。
cd ~
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/bin/cfssl-certinfo
如果上述资源无法下载,可以到微云下载: https://share.weiyun.com/aU7axzGi
2、生成Etcd证书
2.1 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
cfssl gencert -initca ca-csr.json | cfssljson -bare ca -
ls *pem

2.2 使用自签CA签发Etcd HTTPS证书
创建证书申请文件:(注意替换自己的IP)
cat > server-csr.json << EOF
{
"CN": "etcd",
"hosts": [
"192.168.31.71"
],
"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
ls server*pem

部署Etcd
以下步骤在mster上操作
4.1从Github下载二进制文件
cd ~
wget https://github.com/etcd-io/etcd/releases/download/v3.4.9/etcd-v3.4.9-linux-amd64.tar.gz
如果上述资源无法下载,可以到微云下载: https://share.weiyun.com/FxkdQ6cg
4.2 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/
4.3 创建etcd配置文件 (注意替换自己的IP)
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://192.168.31.71:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.31.71:2379"
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.31.71:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.31.71:2379"
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.31.71:2380"
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_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
4.4 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=/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
4.5 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 /opt/etcd/ssl/
4.6 启动并设置开机启动
systemctl daemon-reload
systemctl start etcd
systemctl enable etcd
systemctl status etcd
4.8 查看集群状态 (注意替换自己的IP)
ETCDCTL_API=3 /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://192.168.31.71:2379" endpoint health

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
FAQ:https://cloud.tencent.com/developer/ask/sof/1245533
三、安装Docker
这里采用二进制安装,用yum安装也一样
下载Docker
cd ~
wget https://download.docker.com/linux/static/stable/x86_64/docker-19.03.9.tgz
如果上述资源无法下载,可以到微云: https://share.weiyun.com/WejY4OoZ
2、解压二进制包
tar zxvf docker-19.03.9.tgz
mv docker/* /usr/bin
3、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
4、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
5、启动并设置开机启动
systemctl daemon-reload
systemctl start docker
systemctl enable docker
systemctl status docker
四、部署Master 组件
以下操作Master 上执行
1、生成kube-apiserver证书
1.1 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

1.2 使用自签CA签发kube-apiserver HTTPS证书
创建证书申请文件:(注意替换自己的IP)
cd ~/TLS/k8s
cat > server-csr.json << EOF
{
"CN": "kubernetes",
"hosts": [
"10.0.0.1",
"127.0.0.1",
"192.168.31.71",
"192.168.31.72",
"192.168.31.73",
"192.168.31.74",
"192.168.31.81",
"192.168.31.82",
"192.168.31.88",
"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
ls server*pem

2.从Github下载二进制文件
cd ~
wget https://dl.k8s.io/v1.19.3/kubernetes-server-linux-amd64.tar.gz
上述资源包的下载地址: https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.19.md
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。
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、部署kube-apiserver
4.1 创建配置文件(注意替换自己的IP)
cat > /opt/kubernetes/cfg/kube-apiserver.conf << EOF
KUBE_APISERVER_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--etcd-servers=https://192.168.31.71:2379 \\
--bind-address=192.168.31.71 \\
--secure-port=6443 \\
--advertise-address=192.168.31.71 \\
--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 \\
--etcd-cafile=/opt/etcd/ssl/ca.pem \\
--etcd-certfile=/opt/etcd/ssl/server.pem \\
--etcd-keyfile=/opt/etcd/ssl/server-key.pem \\
--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
–etcd-xxxfile:连接Etcd集群证书
–audit-log-xxx:审计日志
4.2 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/
4.3 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:

创建上述配置文件中token文件:
cat > /opt/kubernetes/cfg/token.csv << EOF
9a8d5e0cc0462ff96833b2327b10ff48,kubelet-bootstrap,10001,"system:node-bootstrapper"
EOF
格式:token,用户名,UID,用户组
上述的token也可用此命令自行生成替换:head -c 16 /dev/urandom | od -An -t x | tr -d ' '
4.4 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
4.5 启动并设置开机启动
systemctl daemon-reload
systemctl start kube-apiserver
systemctl enable kube-apiserver
systemctl status kube-apiserver.service
4.6 授权kubelet-bootstrap用户允许请求证书
kubectl create clusterrolebinding kubelet-bootstrap \
--clusterrole=system:node-bootstrapper \
--user=kubelet-bootstrap
5、部署kube-controller-manager
5.1 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 \\
--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=/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 \\
--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
5.2 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=/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
5.3 启动并设置开机启动
systemctl daemon-reload
systemctl start kube-controller-manager
systemctl enable kube-controller-manager
systemctl status kube-controller-manager
6、部署 kube-scheduler
6.1 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 \
--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)
6.2 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=/opt/kubernetes/cfg/kube-scheduler.conf
ExecStart=/opt/kubernetes/bin/kube-scheduler \$KUBE_SCHEDULER_OPTS
Restart=on-failure
[Install]
WantedBy=multi-user.target
EOF
6.3 启动并设置开机启动
systemctl daemon-reload
systemctl start kube-scheduler
systemctl enable kube-scheduler
systemctl status kube-scheduler
6.4 查看集群状态
生成 kubectl 连接集群的证书:
cd ~/TLS/k8s/
cat > admin-csr.json <<EOF
{
"CN": "admin",
"hosts": [],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "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
下面配置注意替换自己的IP
cd ~/TLS/k8s/
mkdir /root/.kube
# 设置集群参数
kubectl config set-cluster kubernetes \
--certificate-authority=/opt/kubernetes/ssl/ca.pem \
--embed-certs=true \
--server=https://192.168.31.71:6443 \
--kubeconfig=/root/.kube/config
# 设置客户端认证参数
kubectl config set-credentials admin \
--client-certificate=./admin.pem \
--client-key=./admin-key.pem \
--embed-certs=true \
--kubeconfig=/root/.kube/config
# 设置上下文参数
kubectl config set-context default \
--cluster=kubernetes \
--user=admin \
--kubeconfig=/root/.kube/config
# 设置默认上下文
kubectl config use-context default \
--kubeconfig=/root/.kube/config
所有组件都已经启动成功,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。
五、 部署Master Node组件
下面在Master 操作,Master同时作为Worker Node
1、创建工作目录并拷贝二进制文件
创建工作目录:
mkdir -p /opt/kubernetes/{bin,cfg,ssl,logs}
拷贝二进制文件:
cd ~/kubernetes/server/bin
cp kubelet kube-proxy /opt/kubernetes/bin # 本地拷贝
2.部署kubelet
2.1 创建配置文件 (如果改了主机名注意修改hostname-override)
cat > /opt/kubernetes/cfg/kubelet.conf << EOF
KUBELET_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--hostname-override=k8s-master \\
--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
2.2、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
2.3、生成bootstrap.kubeconfig文件 (注意替换自己的IP)
KUBE_APISERVER="https://192.168.31.71:6443" # apiserver IP:PORT
TOKEN="9a8d5e0cc0462ff96833b2327b10ff48" # 与token.csv里保持一致
# 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=${KUBE_APISERVER} \
--kubeconfig=bootstrap.kubeconfig
kubectl config set-credentials "kubelet-bootstrap" \
--token=${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 /opt/kubernetes/cfg
2.4、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
2.5、启动并设置开机启动
systemctl daemon-reload
systemctl start kubelet
systemctl enable kubelet
systemctl status kubelet
2.6、批准kubelet证书申请并加入集群 (注意替换值)
kubectl get csr
CSR_NAME=`kubectl get csr |grep Pending | awk '{print $1}'`
for i in ${CSR_NAME}; do kubectl certificate approve ${i[@]}; done
kubectl get csr

# 查看节点
kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master NotReady <none> 7s v1.18.3
注:由于网络插件还没有部署,节点会没有准备就绪 NotReady
3、 部署kube-proxy
3.1、 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 \
--feature-gates=SupportIPVSProxyMode=true \
--proxy-mode=ipvs"
EOF
3.2、配置参数文件(如果改了主机名注意修改hostnameOverride)
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-master
clusterCIDR: 10.0.0.0/24
mode: "ipvs"
EOF
3.3、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

生成kubeconfig文件:(注意替换自己的IP)
KUBE_APISERVER="https://192.168.31.71:6443"
kubectl config set-cluster kubernetes \
--certificate-authority=/opt/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 /opt/kubernetes/cfg/
3.4、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
3.5、启动并设置开机启动
systemctl daemon-reload
systemctl start kube-proxy
systemctl enable kube-proxy
systemctl status kube-proxy
4、部署CNI网络
4.1 先准备好CNI二进制文件:
cd ~
wget https://github.com/containernetworking/plugins/releases/download/v0.8.6/cni-plugins-linux-amd64-v0.8.6.tgz
如果上述资源无法下载,可以到微云下载: https://share.weiyun.com/EXo38CrR
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
4.1 部署flannel:
wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
flannel 微云: https://share.weiyun.com/KYspLPkY
#默认镜像地址无法访问,修改为docker hub镜像仓库。
sed -i -r "s#quay.io/coreos/flannel:.*-amd64#lizhenliang/flannel:v0.12.0-amd64#g" kube-flannel.yml
#创建
kubectl apply -f kube-flannel.yml
#查看
kubectl get pods -n kube-flannel
NAME READY STATUS RESTARTS AGE
kube-flannel-ds-amd64-2pc95 1/1 Running 0 72s
#部署好网络插件,Node准备就绪
kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master Ready <none> 41m v1.18.3
5、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
6、配置 kubectl 命令行补全
kubectl 命令参数十分复杂,且 pod 名称多含有随机的标识。因此命令行补全功能十分重要。
yum install -y bash-completion
mkdir -p /etc/bash_completion.d/
kubectl completion bash > /etc/bash_completion.d/kubectl # 添加命令行补全
source /etc/bash_completion.d/kubectl # 补全会在下次登录时加载,如需在当前会话补全,主动加载之。
七、Worker Node
1、Node 系统初始化:
master 机器上操作,与Node免密:
KUBERNETES_NODE_LIST='192.168.31.72 192.168.31.73cop'
[ ! -f $HOME/.ssh/id_rsa ] && ssh-keygen -t rsa -b 2048 -N "" -f $HOME/.ssh/id_rsa
if ! grep -Ff $HOME/.ssh/id_rsa.pub $HOME/.ssh/authorized_keys &>/dev/null; then
cat $HOME/.ssh/id_rsa.pub >>$HOME/.ssh/authorized_keys
fi
chmod 600 $HOME/.ssh/authorized_keys
for ip in ${KUBERNETES_NODE_LIST[@]}; do
ssh-copy-id -o StrictHostKeyChecking=no -o CheckHostIP=no root@$ip
done
以下操作在所有node 上执行
# 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
192.168.31.71 k8s-master
192.168.31.72 k8s-node1
192.168.31.73 k8s-node2
EOF
# 将桥接的IPv4流量传递到ipvs
yum install ipset ipvsadm -y
cat >> /etc/sysctl.conf << EOF
net.ipv4.ip_forward=1
EOF
#内核模块加载
cat > /etc/sysconfig/modules/ipvs.modules <<EOF
#!/bin/bash
ipvs_modules="ip_vs ip_vs_lc ip_vs_wlc ip_vs_rr ip_vs_wrr ip_vs_lblc ip_vs_lblcr ip_vs_dh ip_vs_sh ip_vs_fo ip_vs_nq ip_vs_sed ip_vs_ftp nf_conntrack_ipv4"
for kernel_module in \${ipvs_modules}; do
/sbin/modinfo -F filename \${kernel_module} > /dev/null 2>&1
if [ $? -eq 0 ]; then
/sbin/modprobe \${kernel_module}
fi
done
EOF
chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules && lsmod | grep ip_vs
sysctl -p # 生效
# 时间同步
yum install ntpdate -y
ntpdate time.windows.com
2、安装Docker
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
下载Docker
wget https://download.docker.com/linux/static/stable/x86_64/docker-19.03.9.tgz
解压二进制包
tar zxvf docker-19.03.9.tgz
mv docker/* /usr/bin
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
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
启动并设置开机启动
systemctl daemon-reload
systemctl start docker
systemctl enable docker
systemctl status docker
2、拷贝已部署好的Node相关文件到新节点
在master节点操作,将Worker Node涉及文件拷贝到新节点192.168.31.72、192.168.31.73
KUBERNETES_NODE_LIST='192.168.31.72 192.168.31.73'
for i in ${KUBERNETES_NODE_LIST[@]};
do
mkdir -p /run/flannel/;
scp /run/flannel/subnet.env root@${i[@]}:/run/flannel/;
scp -r /opt/kubernetes root@${i}:/opt/;
scp -r /usr/lib/systemd/system/{kubelet,kube-proxy}.service root@${i}:/usr/lib/systemd/system;
scp -r /opt/cni/ root@${i}:/opt/;
scp /opt/kubernetes/ssl/ca.pem root@${i}:/opt/kubernetes/ssl;
done
3、手动在每台node上执行,删除kubelet证书和kubeconfig文件
rm -rf /opt/kubernetes/cfg/kubelet.kubeconfig
rm -rf /opt/kubernetes/ssl/kubelet*
4、手动在每台node上执行, 修改配置文件中的主机名(如果的master主机名不是 k8s-master ,注意修改)
export HOSTNAME=`hostname`
sed -i s/master/"$HOSTNAME"/ /opt/kubernetes/cfg/kubelet.conf
sed -i s/master/"$HOSTNAME"/ /opt/kubernetes/cfg/kube-proxy-config.yml
5、手动在每台node上执行,启动并设置开机启动
systemctl daemon-reload
systemctl restart kubelet
systemctl enable kubelet
systemctl status kubelet
systemctl restart kube-proxy
systemctl enable kube-proxy
systemctl status kube-proxy
6、 在 Master上执行,批准新Node kubelet证书申请
CSR_NAME=`kubectl get csr |grep Pending | awk '{print $1}'`
for i in ${CSR_NAME}; do kubectl certificate approve ${i[@]}; done
kubectl get csr

7、查看Node状态
kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master Ready <none> 65m v1.18.3
k8s-node1 Ready <none> 12m v1.18.3
k8s-node2 Ready <none> 81s v1.18.3
如果是noready ,需等几分钟,再看看
八、部署 Dashboard 和 CoreDNS
1、部署Dashboard
wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-beta8/aio/deploy/recommended.yaml
默认Dashboard只能集群内部访问,修改Service为NodePort类型,暴露到外部:
vi recommended.yaml
kind: Service
apiVersion: v1
metadata:
labels:
k8s-app: kubernetes-dashboard
name: kubernetes-dashboard
namespace: kubernetes-dashboard
spec:
ports:
- port: 443
targetPort: 8443
nodePort: 30001
type: NodePort
selector:
k8s-app: kubernetes-dashboard
kubectl apply -f recommended.yaml
kubectl get pods,svc -n kubernetes-dashboard
NAME READY STATUS RESTARTS AGE
pod/dashboard-metrics-scraper-694557449d-z8gfb 1/1 Running 0 2m18s
pod/kubernetes-dashboard-9774cc786-q2gsx 1/1 Running 0 2m19s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/dashboard-metrics-scraper ClusterIP 10.0.0.141 <none> 8000/TCP 2m19s
service/kubernetes-dashboard NodePort 10.0.0.239 <none> 443:30001/TCP 2m19s
访问地址:https://NodeIP:30001
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}')
使用输出的token登录Dashboard。
2、部署CoreDNS
CoreDNS用于集群内部Service名称解析。
下载coredns.yaml
wget https://www.centoscn.vip/wp-content/uploads/2020/09/coredns.yaml_.zip
微云下载: https://share.weiyun.com/9a5fhv4v
解压包
unzip coredns.yaml_.zip
kubectl apply -f coredns.yaml
kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
coredns-5ffbfd976d-j6shb 1/1 Running 0 32s
kube-flannel-ds-amd64-2pc95 1/1 Running 0 38m
kube-flannel-ds-amd64-7qhdx 1/1 Running 0 15m
kube-flannel-ds-amd64-99cr8 1/1 Running 0 26m
FAQ:
The Deployment "coredns" is invalid: spec.selector: Invalid value: v1.LabelSelector{MatchLabels:map[string]string{"k8s-app":"kube-dns"}, MatchExpressions:[]v1.LabelSelectorRequirement(nil)}: field is immutable
之前部署过coredns,要把之前部署的deployment 删除,再部署
https://github.com/coredns/deployment/issues/201
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