Kubernetes高可用集群二进制部署（二）ETCD集群部署

Kubernetes概述
使用kubeadm快速部署一个k8s集群
Kubernetes高可用集群二进制部署（一）主机准备和负载均衡器安装
Kubernetes高可用集群二进制部署（二）ETCD集群部署
Kubernetes高可用集群二进制部署（三）部署api-server
Kubernetes高可用集群二进制部署（四）部署kubectl和kube-controller-manager、kube-scheduler
Kubernetes高可用集群二进制部署（五）kubelet、kube-proxy、Calico、CoreDNS
Kubernetes高可用集群二进制部署（六）Kubernetes集群节点添加

1. 配置免密登录

在k8s-master1上操作

生成密钥对，把公钥复制到远程主机

ssh-keygen
#直接回车，不设置密码

ssh-copy-id root@k8s-master1
ssh-copy-id root@k8s-master2
ssh-copy-id root@k8s-master3
ssh-copy-id root@k8s-worker1

ssh root@k8s-master1
#依次此时是否能否正常登录

2 部署ETCD集群

在k8s-master1上操作。

2.1 创建工作目录

mkdir -p /data/k8s-work

2.2 获取cfssl工具

cd /data/k8s-work
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

说明：
cfssl是使用go编写，由CloudFlare开源的一款PKI/TLS工具。主要程序有：- cfssl，是CFSSL的命令行工具
- cfssljson用来从cfssl程序获取JSON输出，并将证书，密钥，CSR和bundle写入文件中。

chmod +x cfssl*

mv cfssl_linux-amd64 /usr/local/bin/cfssl
mv cfssljson_linux-amd64 /usr/local/bin/cfssljson
mv cfssl-certinfo_linux-amd64 /usr/local/bin/cfssl-certinfo

# cfssl version
Version: 1.2.0
Revision: dev
Runtime: go1.6

2.3 创建CA证书

在master1上创建证书

2.3.1 配置ca证书请求文件

在当前目录/data/k8s-work执行

cat > ca-csr.json <<"EOF"
{"CN": "kubernetes","key": {"algo": "rsa","size": 2048},"names": [{"C": "CN","ST": "Beijing","L": "Beijing","O": "kubemsb","OU": "CN"}],"ca": {"expiry": "87600h"}
}
EOF

2.3.2 创建ca证书

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

2.3.3 配置ca证书策略

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

server auth 表示client可以对使用该ca对server提供的证书进行验证client auth 表示server可以使用该ca对client提供的证书进行验证

2.4 创建etcd证书

2.4.1 配置etcd请求文件

一般可以部署三台集群，可以是3、5、7、9

cat > etcd-csr.json <<"EOF"
{"CN": "etcd","hosts": ["127.0.0.1","192.168.10.103","192.168.10.104","192.168.10.105"],"key": {"algo": "rsa","size": 2048},"names": [{"C": "CN","ST": "Beijing","L": "Beijing","O": "kubemsb","OU": "CN"}]
}
EOF

2.4.2 生成etcd证书

确保在当前目录有ca-key.pem、ca-config.json、etcd-csr.json文件

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

# ls
输出
ca-config.json  ca.csr  ca-csr.json  ca-key.pem  ca.pem  etcd.csr  etcd-csr.json  etcd-key.pem  etcd.pem

etcd.csr：etcd证书请求文件
etcd-key.pem：私钥
etcd.pem：基于私钥签发的证书

2.5 部署etcd集群

2.5.1 下载etcd软件包

etcd releases

wget https://github.com/etcd-io/etcd/releases/download/v3.5.2/etcd-v3.5.2-linux-amd64.tar.gz

2.5.2 安装etcd软件

tar -xvf etcd-v3.5.2-linux-amd64.tar.gz
cp -p etcd-v3.5.2-linux-amd64/etcd* /usr/local/bin/
#-p 保留源文件的权限

2.5.3 分发etcd软件

scp etcd-v3.5.2-linux-amd64/etcd* k8s-master2:/usr/local/bin/scp etcd-v3.5.2-linux-amd64/etcd* k8s-master3:/usr/local/bin/

2.5.4 创建配置文件

在三个etcd节点操作

mkdir /etc/etcd

其中地址都是当前主机的ip本身

cat >  /etc/etcd/etcd.conf <<"EOF"
#[Member]
ETCD_NAME="etcd1"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.10.103:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.10.103:2379,http://127.0.0.1:2379"#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.10.103:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.10.103:2379"
ETCD_INITIAL_CLUSTER="etcd1=https://192.168.10.103:2380,etcd2=https://192.168.10.104:2380,etcd3=https://192.168.10.105:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
EOF

说明：
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

2.5.5 创建服务配置文件

mkdir -p /etc/etcd/ssl
mkdir -p /var/lib/etcd/default.etcd

cd /data/k8s-work
cp ca*.pem /etc/etcd/ssl
cp etcd*.pem /etc/etcd/ssl

cat > /etc/systemd/system/etcd.service <<"EOF"
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target[Service]
Type=notify
EnvironmentFile=-/etc/etcd/etcd.conf
WorkingDirectory=/var/lib/etcd/
ExecStart=/usr/local/bin/etcd \--cert-file=/etc/etcd/ssl/etcd.pem \--key-file=/etc/etcd/ssl/etcd-key.pem \--trusted-ca-file=/etc/etcd/ssl/ca.pem \--peer-cert-file=/etc/etcd/ssl/etcd.pem \--peer-key-file=/etc/etcd/ssl/etcd-key.pem \--peer-trusted-ca-file=/etc/etcd/ssl/ca.pem \--peer-client-cert-auth \--client-cert-auth
Restart=on-failure
RestartSec=5
LimitNOFILE=65536[Install]
WantedBy=multi-user.target
EOF

2.5.6 同步etcd配置到集群其它master节点

创建目录
mkdir -p /etc/etcd
mkdir -p /etc/etcd/ssl
mkdir -p /var/lib/etcd/default.etcd

服务配置文件,需要修改etcd节点名称及IP地址
for i in k8s-master2 k8s-master3
do
scp /etc/etcd/etcd.conf $i:/etc/etcd/
done

k8s-master2:cat /etc/etcd/etcd.conf
#[Member]
ETCD_NAME="etcd2"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.10.104:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.10.104:2379,http://127.0.0.1:2379"#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.10.104:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.10.104:2379"
ETCD_INITIAL_CLUSTER="etcd1=https://192.168.10.103:2380,etcd2=https://192.168.10.104:2380,etcd3=https://192.168.10.105:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"

k8s-master3:cat /etc/etcd/etcd.conf
#[Member]
ETCD_NAME="etcd3"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.10.105:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.10.105:2379,http://127.0.0.1:2379"#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.10.105:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.10.105:2379"
ETCD_INITIAL_CLUSTER="etcd1=https://192.168.10.103:2380,etcd2=https://192.168.10.104:2380,etcd3=https://192.168.10.105:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"

证书文件
for i in k8s-master2 k8s-master3
do
scp /etc/etcd/ssl/* $i:/etc/etcd/ssl
done

服务启动配置文件
for i in k8s-master2 k8s-master3
do
scp /etc/systemd/system/etcd.service $i:/etc/systemd/system/
done

2.5.7 启动etcd集群

三台主机全都执行

systemctl daemon-reload
systemctl enable --now etcd.service  #现在开启并设置开机自启
systemctl status etcd

2.5.8 验证集群状态

ETCDCTL_API=3 /usr/local/bin/etcdctl --write-out=table --cacert=/etc/etcd/ssl/ca.pem --cert=/etc/etcd/ssl/etcd.pem --key=/etc/etcd/ssl/etcd-key.pem --endpoints=https://192.168.10.103:2379,https://192.168.10.104:2379,https://192.168.10.105:2379 endpoint health

+-----------------------------+--------+------------+-------+
|          ENDPOINT           | HEALTH |    TOOK    | ERROR |
+-----------------------------+--------+------------+-------+
| https://192.168.10.103:2379 |   true | 6.961777ms |       |
| https://192.168.10.105:2379 |   true | 6.594067ms |       |
| https://192.168.10.104:2379 |   true | 6.835899ms |       |
+-----------------------------+--------+------------+-------+

耗时较长的话可以做一些优化工作