使用二进制文件部署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。

主机规划

节点名称	IP
etcd-1,k8s-master	192.168.80.220
etcd-2,k8s-node1	192.168.80.221
etcd-3,k8s-node1	192.168.80.222

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
192.168.80.220 k8s-master1
192.168.80.221 k8s-node1
192.168.80.222 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

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

若是下载不了的话可以用我下载好的这个：https://files.cnblogs.com/files/sanduzxcvbnm/etcd集群生成证书的工具.zip

生成Etcd证书

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,会生成ca.pem和ca-key.pem文件
cfssl gencert -initca ca-csr.json | cfssljson -bare ca -

使用自签CA签发Etcd HTTPS证书

# 创建证书申请文件
# 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。
cat > server-csr.json << EOF
{
    "CN": "etcd",
    "hosts": [
    "192.168.80.220",
    "192.168.80.221",
    "192.168.80.222",
    "192.168.80.223",
    "192.168.80.224",
    "192.168.80.225"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "BeiJing",
            "ST": "BeiJing"
        }
    ]
}
EOF

# 生成证书,会生成server.pem和server-key.pem文件
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=www server-csr.json | cfssljson -bare server

从Github下载二进制文件

可以使用迅雷下载
https://github.com/etcd-io/etcd/releases/download/v3.5.0/etcd-v3.5.0-linux-amd64.tar.gz

百度云网盘分享地址
链接：https://pan.baidu.com/s/1LvnMZSGgwafkH3Bdce-s8A
提取码：40bc

部署Etcd集群

以下在节点etcd-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.

# 创建工作目录并解压二进制包
mkdir /opt/etcd/{bin,cfg,ssl} -p
tar zxvf etcd-v3.5.0-linux-amd64.tar.gz
mv etcd-v3.5.0-linux-amd64/{etcd,etcdctl} /opt/etcd/bin/

# 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://192.168.80.220:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.80.220:2379"

#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.80.220:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.80.220:2379"
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.80.220:2380,etcd-2=https://192.168.80.221:2380,etcd-3=https://192.168.80.222:2380"
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_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

# 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

# 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/

# 启动并设置开机启动
systemctl daemon-reload
systemctl start etcd  # 第一个节点启动比较慢，是连接另外俩节点连接不上超时导致的，等另外俩节点的etcd起来后状态就正常了
systemctl enable etcd

# 将上面节点etcd-1所有生成的文件拷贝到节点etcd-2和节点etcd-3
scp -r /opt/etcd/ root@192.168.80.221:/opt/
scp /usr/lib/systemd/system/etcd.service root@192.168.80.221:/usr/lib/systemd/system/
scp -r /opt/etcd/ root@192.168.80.222:/opt/
scp /usr/lib/systemd/system/etcd.service root@192.168.80.222:/usr/lib/systemd/system/

# 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
vim /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://192.168.80.220:2380"     # 修改此处为当前服务器IP
ETCD_LISTEN_CLIENT_URLS="https://192.168.80.220:2379"   # 修改此处为当前服务器IP

#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.80.220:2380" # 修改此处为当前服务器IP
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.80.220:2379"       # 修改此处为当前服务器IP
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.80.220:2380,etcd-2=https://192.168.80.221:2380,etcd-3=https://192.168.80.222:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"

# 最后启动etcd并设置开机启动,操作命令同上

查看集群状态

/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://192.168.80.220:2379,https://192.168.80.221:2379,https://192.168.80.222:2379" endpoint health --write-out=table

+-----------------------------+--------+------------+-------+
|          ENDPOINT           | HEALTH |    TOOK    | ERROR |
+-----------------------------+--------+------------+-------+
| https://192.168.80.220:2379 |   true | 7.327348ms |       |
| https://192.168.80.221:2379 |   true | 7.532873ms |       |
| https://192.168.80.222:2379 |   true | 7.732458ms |       |
+-----------------------------+--------+------------+-------+

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