基于k8s的多master高可用集群部署项目

先部署单master集群，后扩展master节点为多节点
角色 IP 组件

k8s-master1 192.168.31.71 kube-apiserver，kube-controller-manager，kube-scheduler，kubelet，kube-proxy，docker，etcd， nginx，keepalived k8s-master2 192.168.31.74 kube-apiserver，kube-controller-manager，kube-scheduler，kubelet，kube-proxy，docker， nginx，keepalived k8s-node1 192.168.31.72 kubelet，kube-proxy，docker，etcd k8s-node2 192.168.31.73 kubelet，kube-proxy，docker，etcd 负载均衡器IP 192.168.31.88 (VIP)

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-master1 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

部署Etcd集群

为解决Etcd单点故障，本实验采用集群方式部署，这里使用3台组建集群，可容忍1台机器故障
注意：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。

cfssl是一个开源的证书管理工具，使用json文件生成证书
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

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 -

会生成ca.pem和ca-key.pem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

会生成server.pem和server-key.pem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

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.

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/

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

变量详解：

•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

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

cp ~/TLS/etcd/ca*pem ~/TLS/etcd/server*pem /opt/etcd/ssl/

systemctl daemon-reload systemctl start etcd systemctl enable etcd

scp -r /opt/etcd/ root@192.168.31.72:/opt/ scp /usr/lib/systemd/system/etcd.service root@192.168.31.72:/usr/lib/systemd/system/ scp -r /opt/etcd/ root@192.168.31.73:/opt/ scp /usr/lib/systemd/system/etcd.service root@192.168.31.73:/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。

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 --write-out=table +----------------------------+--------+-------------+-------+ | ENDPOINT | HEALTH | TOOK | ERROR | +----------------------------+--------+-------------+-------+ | https://192.168.31.71:2379 | true | 10.301506ms | | | https://192.168.31.73:2379 | true | 12.87467ms | | | https://192.168.31.72:2379 | 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

部署docker环境，使用Docker作为容器引擎

安装配置请参考另外一篇博文

部署Master Node

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。

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", "192.168.31.88", "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

会生成server.pem和server-key.pem文件

Github下载二进制文件
下载地址： https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.20.md
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。
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/

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 \\ --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

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/

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。

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 ' '

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

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

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