集群初始化脚本

用于一键部署集群（多节点）的环境初始化，如修改主机名，禁用防火墙、selinux、iptables，主机映射，节点相互免密，时间同步等
ps：脚本需要下载except，chrony等软件包，确保centos源正常

脚本实现

#!/bin/bash

# 定义节点信息
NODES=("192.168.200.80 cluster01" "192.168.200.81 cluster02" "192.168.200.82 cluster03")

# 定义当前节点的密码（默认集群统一密码）
HOST_PASS="000000"

# 时间同步的目标节点
TIME_SERVER=cluster01

# 时间同步的地址段
TIME_SERVER_IP=192.160.200.0/24

# 欢迎界面
cat > /etc/motd <################################
 #    Welcome  to  mycluster    #
 ################################
EOF

#禁用selinux
sed -i 's/SELINUX=.*/SELINUX=disabled/g' /etc/selinux/config
setenforce 0

#firewalld
systemctl stop firewalld
systemctl disable firewalld  >> /dev/null 2>&1

#关闭IPtables，清空规则
yum install  iptables-services  -y 
if [ 0  -ne  $? ]; then
        echo -e "\033[31mThe installation source configuration errors\033[0m"
        exit 1
fi
systemctl restart iptables
iptables -F
iptables -X
iptables -Z 
/usr/sbin/iptables-save
systemctl stop iptables
systemctl disable iptables

#禁用NetworkManager
systemctl stop NetworkManager >> /dev/null 2>&1
systemctl disable NetworkManager >> /dev/null 2>&1
yum remove -y NetworkManager firewalld
systemctl restart network

# 优化ssh连接
sed -i -e 's/#UseDNS yes/UseDNS no/g' -e 's/GSSAPIAuthentication yes/GSSAPIAuthentication no/g' /etc/ssh/sshd_config
systemctl reload sshd

# 修改主机名
for node in "${NODES[@]}"; do
  ip=$(echo "$node" | awk '{print $1}')
  hostname=$(echo "$node" | awk '{print $2}')

  # 获取当前节点的主机名和 IP
  current_ip=$(hostname -I | awk '{print $1}')
  current_hostname=$(hostname)

  # 检查当前节点与要修改的节点信息是否匹配
  if [[ "$current_ip" == "$ip" && "$current_hostname" != "$hostname" ]]; then
    echo "Updating hostname to $hostname on $current_ip..."
    hostnamectl set-hostname "$hostname"

    if [ $? -eq 0 ]; then
      echo "Hostname updated successfully."
    else
      echo "Failed to update hostname."
    fi

    break
  fi
done

# 遍历节点信息并添加到 hosts 文件
for node in "${NODES[@]}"; do
  ip=$(echo "$node" | awk '{print $1}')
  hostname=$(echo "$node" | awk '{print $2}')

  # 检查 hosts 文件中是否已存在相应的解析
  if grep -q "$ip $hostname" /etc/hosts; then
    echo "Host entry for $hostname already exists in /etc/hosts."
  else
    # 添加节点的解析条目到 hosts 文件
    sudo sh -c "echo '$ip $hostname' >> /etc/hosts"
    echo "Added host entry for $hostname in /etc/hosts."
  fi
done

if [[ ! -s ~/.ssh/id_rsa.pub ]]; then
    ssh-keygen -t rsa -N '' -f ~/.ssh/id_rsa -q -b 2048
fi

# 检查并安装 expect 工具
if ! which expect &> /dev/null; then
    echo "expect 工具未安装，正在安装 expect..."
    sudo yum install -y expect
fi

# 遍历所有节点
for node in "${NODES[@]}"; do
    ip=$(echo "$node" | awk '{print $1}')
    hostname=$(echo "$node" | awk '{print $2}')

    expect -c "
        set timeout -1
        spawn ssh-copy-id -i /root/.ssh/id_rsa.pub $hostname
        expect {
            \"*password:*\" { send -- \"$HOST_PASS\r\"; exp_continue }
            \"*(yes/no)*\" { send -- \"yes\r\"; exp_continue }
            eof { exit 1 }
        }
    "
done

# 时间同步
if [[ $name == $TIME_SERVER ]]; then
    # 配置当前节点为时间同步源
    sed -i '3,6s/^/#/g' /etc/chrony.conf
    sed -i "7s/^/server $TIME_SERVER iburst/g" /etc/chrony.conf
    echo "allow $TIME_SERVER_IP" >> /etc/chrony.conf
    echo "local stratum 10" >> /etc/chrony.conf
else
    # 配置当前节点同步到目标节点
    sed -i '3,6s/^/#/g' /etc/chrony.conf
    sed -i "7s/^/server $TIME_SERVER iburst/g" /etc/chrony.conf
fi

# 重启并启用 chrony 服务
systemctl restart chronyd
systemctl enable chronyd

echo "###############################################################"
echo "#################      集群初始化成功     #####################"
echo "###############################################################"

脚本测试

节点	IP
cluster01	192.168.200.80
cluster02	192.168.200.81
cluster03	192.168.200.82

yum源仓库正常，离线环境配置centos7.9离线源即可

[root@localhost ~]# yum clean all;yum repolist
Loaded plugins: fastestmirror
Cleaning repos: base extras updates
Cleaning up list of fastest mirrors
Loaded plugins: fastestmirror
Determining fastest mirrors
 * base: mirrors.bfsu.edu.cn
 * extras: mirrors.bfsu.edu.cn
 * updates: mirrors.tuna.tsinghua.edu.cn
base                                                                                             | 3.6 kB  00:00:00
extras                                                                                           | 2.9 kB  00:00:00
updates                                                                                          | 2.9 kB  00:00:00
(1/4): base/7/x86_64/group_gz                                                                    | 153 kB  00:00:00
(2/4): extras/7/x86_64/primary_db                                                                | 249 kB  00:00:00
(3/4): base/7/x86_64/primary_db                                                                  | 6.1 MB  00:00:02
(4/4): updates/7/x86_64/primary_db                                                               |  21 MB  00:00:04
repo id                                                 repo name                                                 status
base/7/x86_64                                           CentOS-7 - Base                                           10,072
extras/7/x86_64                                         CentOS-7 - Extras                                            515
updates/7/x86_64                                        CentOS-7 - Updates                                         4,996
repolist: 15,583

三台节点运行脚本测试

[root@localhost ~]# cat init.sh
#!/bin/bash

# 定义节点信息
NODES=("192.168.200.80 cluster01" "192.168.200.81 cluster02" "192.168.200.82 cluster03")

# 定义当前节点的密码（默认集群统一密码）
HOST_PASS="000000"

# 时间同步的目标节点
TIME_SERVER= cluster01

# 时间同步的地址段
TIME_SERVER_IP= 192.160.200.0/24

# 欢迎界面
cat > /etc/motd <################################
 #    Welcome  to  mycluster    #
 ################################
EOF

#禁用selinux
sed -i 's/SELINUX=.*/SELINUX=disabled/g' /etc/selinux/config
setenforce 0

#firewalld
systemctl stop firewalld
systemctl disable firewalld  >> /dev/null 2>&1

#关闭IPtables，清空规则
yum install  iptables-services  -y
if [ 0  -ne  $? ]; then
        echo -e "\033[31mThe installation source configuration errors\033[0m"
        exit 1
fi
systemctl restart iptables
iptables -F
iptables -X
iptables -Z
/usr/sbin/iptables-save
systemctl stop iptables
systemctl disable iptables

#禁用NetworkManager
systemctl stop NetworkManager >> /dev/null 2>&1
systemctl disable NetworkManager >> /dev/null 2>&1
yum remove -y NetworkManager firewalld
systemctl restart network

# 优化ssh连接
sed -i -e 's/#UseDNS yes/UseDNS no/g' -e 's/GSSAPIAuthentication yes/GSSAPIAuthentication no/g' /etc/ssh/sshd_config
systemctl reload sshd

# 修改主机名
for node in "${NODES[@]}"; do
  ip=$(echo "$node" | awk '{print $1}')
  hostname=$(echo "$node" | awk '{print $2}')

  # 获取当前节点的主机名和 IP
  current_ip=$(hostname -I | awk '{print $1}')
  current_hostname=$(hostname)

  # 检查当前节点与要修改的节点信息是否匹配
  if [[ "$current_ip" == "$ip" && "$current_hostname" != "$hostname" ]]; then
    echo "Updating hostname to $hostname on $current_ip..."
    hostnamectl set-hostname "$hostname"

    if [ $? -eq 0 ]; then
      echo "Hostname updated successfully."
    else
      echo "Failed to update hostname."
    fi

    break
  fi
done

# 遍历节点信息并添加到 hosts 文件
for node in "${NODES[@]}"; do
  ip=$(echo "$node" | awk '{print $1}')
  hostname=$(echo "$node" | awk '{print $2}')

  # 检查 hosts 文件中是否已存在相应的解析
  if grep -q "$ip $hostname" /etc/hosts; then
    echo "Host entry for $hostname already exists in /etc/hosts."
  else
    # 添加节点的解析条目到 hosts 文件
    sudo sh -c "echo '$ip $hostname' >> /etc/hosts"
    echo "Added host entry for $hostname in /etc/hosts."
  fi
done

if [[ ! -s ~/.ssh/id_rsa.pub ]]; then
    ssh-keygen -t rsa -N '' -f ~/.ssh/id_rsa -q -b 2048
fi

# 检查并安装 expect 工具
if ! which expect &> /dev/null; then
    echo "expect 工具未安装，正在安装 expect..."
    sudo yum install -y expect
fi

# 遍历所有节点
for node in "${NODES[@]}"; do
    ip=$(echo "$node" | awk '{print $1}')
    hostname=$(echo "$node" | awk '{print $2}')

    expect -c "
        set timeout -1
        spawn ssh-copy-id -i /root/.ssh/id_rsa.pub $hostname
        expect {
            \"*password:*\" { send -- \"$HOST_PASS\r\"; exp_continue }
            \"*(yes/no)*\" { send -- \"yes\r\"; exp_continue }
            eof { exit 1 }
        }
    "
done

# 时间同步
if [[ $name == $TIME_SERVER ]]; then
    # 配置当前节点为时间同步源
    sed -i '3,6s/^/#/g' /etc/chrony.conf
    sed -i "7s/^/server $TIME_SERVER iburst/g" /etc/chrony.conf
    echo "allow $TIME_SERVER_IP" >> /etc/chrony.conf
    echo "local stratum 10" >> /etc/chrony.conf
else
    # 配置当前节点同步到目标节点
    sed -i '3,6s/^/#/g' /etc/chrony.conf
    sed -i "7s/^/server $TIME_SERVER iburst/g" /etc/chrony.conf
fi

# 重启并启用 chrony 服务
systemctl restart chronyd
systemctl enable chronyd

echo "###############################################################"
echo "#################      集群初始化成功     ######################"
echo "###############################################################"

cluster01验证

[root@localhost ~]# bash
[root@cluster01 ~]# cat /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.200.80 cluster01
192.168.200.81 cluster02
192.168.200.82 cluster03
[root@cluster01 ~]# getenforce
Permissive
[root@cluster01 ~]# systemctl status firewalld
Unit firewalld.service could not be found.
[root@cluster01 ~]# systemctl status iptables
● iptables.service - IPv4 firewall with iptables
   Loaded: loaded (/usr/lib/systemd/system/iptables.service; disabled; vendor preset: disabled)
   Active: inactive (dead) since Sun 2023-06-04 12:04:09 EDT; 1min 14s ago
 Main PID: 2677 (code=exited, status=0/SUCCESS)

Jun 04 12:04:09 localhost.localdomain systemd[1]: Starting IPv4 firewall with iptables...
Jun 04 12:04:09 localhost.localdomain iptables.init[2677]: iptables: Applying firewall rules: [  OK  ]
Jun 04 12:04:09 localhost.localdomain systemd[1]: Started IPv4 firewall with iptables.
Jun 04 12:04:09 localhost.localdomain systemd[1]: Stopping IPv4 firewall with iptables...
Jun 04 12:04:09 localhost.localdomain iptables.init[2710]: iptables: Setting chains to policy ACCEPT: filter [  OK  ]
Jun 04 12:04:09 localhost.localdomain iptables.init[2710]: iptables: Flushing firewall rules: [  OK  ]
Jun 04 12:04:09 localhost.localdomain systemd[1]: Stopped IPv4 firewall with iptables.
[root@cluster01 ~]# ssh cluster01
Last login: Sun Jun  4 12:12:13 2023 from 192.168.200.80
 ################################
 #    Welcome  to  mycluster    #
 ################################
[root@cluster01 ~]# exit
logout
Connection to cluster01 closed.
[root@cluster01 ~]# ssh cluster02
Last login: Sun Jun  4 12:12:17 2023 from 192.168.200.80
 ################################
 #    Welcome  to  mycluster    #
 ################################
[root@cluster02 ~]# exit
logout
Connection to cluster02 closed.
[root@cluster01 ~]# ssh cluster03
Last login: Sun Jun  4 12:12:22 2023 from 192.168.200.80
 ################################
 #    Welcome  to  mycluster    #
 ################################
[root@cluster03 ~]# exit
logout
Connection to cluster03 closed.
[root@cluster01 ~]#

验证时间同步

[root@cluster01 ~]# chronyc sources
210 Number of sources = 1
MS Name/IP address         Stratum Poll Reach LastRx Last sample
===============================================================================
^* cluster01                    10   6   377   360   +983ns[  -15us] +/-   25us
[root@cluster01 ~]#

[root@cluster02 ~]# chronyc sources
210 Number of sources = 1
MS Name/IP address         Stratum Poll Reach LastRx Last sample
===============================================================================
^* cluster01                    11   6   177     2    +55us[ +117us] +/- 1609us
[root@cluster02 ~]#

[root@cluster03 ~]# chronyc sources
210 Number of sources = 0
MS Name/IP address         Stratum Poll Reach LastRx Last sample
===============================================================================
[root@cluster03 ~]#

不仅限于三个节点，多节点亦可，只需修改NODES变量