部署一套完整的Kubernetes高可用集群(二进制,最新版v1.18)上
一、前置知识点
1.1 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。
1.2 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
- 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
1.3 准备环境
软件环境:
软件 | 版本 |
---|---|
操作系统 | CentOS7.8_x64 (mini) |
Docker | 19-ce |
Kubernetes | 1.18 |
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-master2 | 192.168.31.74 | kube-apiserver,kube-controller-manager,kube-scheduler |
k8s-node1 | 192.168.31.72 | kubelet,kube-proxy,docker etcd |
k8s-node2 | 192.168.31.73 | kubelet,kube-proxy,docker,etcd |
Load Balancer(Master) | 192.168.31.81 ,192.168.31.88 (VIP) | Nginx L4 |
Load Balancer(Backup) | 192.168.31. 82 | Nginx L4 |
须知:考虑到有些朋友电脑配置较低,这么多虚拟机跑不动,所以这一套高可用集群分两部分实施,先部署一套单Master架构(192.168.31.71/72/73),再扩容为多Master架构(上述规划),顺便熟悉下Master扩容流程。
单Master架构图:
单Master服务器规划:
角色 | IP | 组件 |
---|---|---|
k8s-master | 192.168.31.71 | kube-apiserver,kube-controller-manager,kube-scheduler,etcd |
k8s-node1 | 192.168.31.72 | kubelet,kube-proxy,docker etcd |
k8s-node2 | 192.168.31.73 | kubelet,kube-proxy,docker,etcd |
1.4 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-1 | 192.168.31.71 |
etcd-2 | 192.168.31.72 |
etcd-3 | 192.168.31.73 |
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/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:
cfssl gencert -initca ca-csr.json | cfssljson -bare ca - ls *pem ca-key.pem ca.pem
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": [ "192.168.31.71", "192.168.31.72", "192.168.31.73" ], "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 server-key.pem server.pem
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
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
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-2=https://192.168.31.72:2380,etcd-3=https://192.168.31.73:2380" 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
3. 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. 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/
5. 启动并设置开机启动
systemctl daemon-reload systemctl start etcd systemctl enable etcd
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/ :/opt/ scp /usr/lib/systemd/system/etcd.service :/usr/lib/systemd/system/ scp -r /opt/etcd/ :/opt/ scp /usr/lib/systemd/system/etcd.service :/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://192.168.31.71:2380" # 修改此处为当前服务器IP ETCD_LISTEN_CLIENT_URLS="https://192.168.31.71:2379" # 修改此处为当前服务器IP #[Clustering] ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.31.71:2380" # 修改此处为当前服务器IP ETCD_ADVERTISE_CLIENT_URLS="https://192.168.31.71:2379" # 修改此处为当前服务器IP ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.31.71:2380,etcd-2=https://192.168.31.72:2380,etcd-3=https://192.168.31.73:2380" 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
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,https://192.168.31.72:2379,https://192.168.31.73:2379" endpoint health https://192.168.31.71:2379 is healthy: successfully committed proposal: took = 8.154404ms https://192.168.31.73:2379 is healthy: successfully committed proposal: took = 9.044117ms https://192.168.31.72:2379 is healthy: successfully committed proposal: took = 10.000825ms
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
下载地址:https://download.docker.com/linux/static/stable/x86_64/docker-19.03.9.tgz
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: init1024
4.1 生成kube-apiserver证书
1. 自签证书颁发机构(CA)
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
2. 使用自签CA签发kube-apiserver HTTPS证书
创建证书申请文件:
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 server-key.pem server.pem
4.2 从Github下载二进制文件
下载地址: https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.18.md#v1183
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
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://192.168.31.71:2379,https://192.168.31.72:2379,https://192.168.31.73:2379 \--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
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:
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
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
4.5 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 \--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
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
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 > /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)
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
3. 启动并设置开机启动
systemctl daemon-reload systemctl start scheduler systemctl enable scheduler
4. 查看集群状态
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: init1024
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:
mkdir -p /opt/kubernetes/{bin,cfg,ssl,logs}
从master节点拷贝:
cd kubernetes/server/bin cp kubelet kube-proxy /opt/kubernetes/bin # 本地拷贝
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-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. 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bootstrap.kubeconfig文件
KUBE_APISERVER="https://192.168.31.71:6443" # apiserver IP:PORT TOKEN="c47ffb939f5ca36231d9e3121a252940" # 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
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
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-uCEGPOIiDdlLODKts8J658HrFq9CZ--K6M4G7bjhk8A 6m3s kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Pending # 批准申请 kubectl certificate approve node-csr-uCEGPOIiDdlLODKts8J658HrFq9CZ--K6M4G7bjhk8A # 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
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-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
生成kubeconfig文件:
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/
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
systemctl daemon-reload systemctl start kube-proxy systemctl enable kube-proxy
5.5 部署CNI网络
先准备好CNI二进制文件:
解压二进制包并移动到默认工作目录:
mkdir /opt/cni/bin tar zxvf cni-plugins-linux-amd64-v0.8.6.tgz -C /opt/cni/bin
部署CNI网络:
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。
kubectl apply -f kube-flannel.yml kubectl get pods -n kube-system NAME READY STATUS RESTARTS AGE kube-flannel-ds-amd64-2pc95 1/1 Running 0 72s kubectl get node NAME STATUS ROLES AGE VERSION k8s-master Ready <none> 41m v1.18.3
部署好网络插件,Node准备就绪。
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 新增加Worker Node
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192.168.31.72/73
scp /opt/kubernetes :/opt/ scp -r /usr/lib/systemd/system/{kubelet,kube-proxy}.service :/usr/lib/systemd/system scp -r /opt/cni/ :/opt/ scp /opt/kubernetes/ssl/ca.pem :/opt/kubernetes/ssl
2. 删除kubelet证书和kubeconfig文件
rm /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,必须删除重新生成。
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 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-4zTjsaVSrhuyhIGqsefxzVoZDCNKei-aE2jyTP81Uro 89s kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Pending kubectl certificate approve node-csr-4zTjsaVSrhuyhIGqsefxzVoZDCNKei-aE2jyTP81Uro
6. 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
Node2(192.168.31.73 )节点同上。记得修改主机名!
六、部署Dashboard和CoreDNS
6.1 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。
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 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
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,单Master集群部署完成,下一篇扩容为多Master集群~