基于centos7.9搭建数据库高可用集群

环境初始化

主机	IP
node1	192.168.200.80
node2	192.168.200.81
node3	192.168.200.82

#!/bin/bash

# 定义节点信息
NODES=("192.168.200.80 node1" "192.168.200.81 node2" "192.168.200.82 node3")

# 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=node1

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

# 欢迎界面
cat > /etc/motd <<EOF
 ################################
 #    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 "###############################################################"

三台节点执行

[root@localhost ~]# bash init.sh

部署集群

配置yum源

[root@node1 ~]# yum install -y vsftpd
[root@node1 ~]# echo anon_root=/opt >> /etc/vsftpd/vsftpd.conf
[root@node1 ~]# systemctl enable --now vsftpd
[root@node1 ~]# tar -xf mariadb-repo.tar.gz -C /opt/
[root@node1 ~]# mkdir /opt/centos
[root@node1 ~]# mount /dev/sr0 /opt/centos/
mount: /dev/sr0 is write-protected, mounting read-only
[root@node1 ~]# ls /opt/
centos  mariadb-repo
[root@node1 ~]# cat /etc/yum.repos.d/ftp.repo
[db]
name=db
baseurl=file:///opt/mariadb-repo
gpgcheck=0
enabled=1
[centos]
name=centos
baseurl=file:///opt/centos
gpgcheck=0
enabled=1
[root@node1 ~]# yum clean all;yum repolist
Loaded plugins: fastestmirror
Cleaning repos: centos db
Cleaning up list of fastest mirrors
Other repos take up 195 M of disk space (use --verbose for details)
Loaded plugins: fastestmirror
Determining fastest mirrors
centos                                                                                           | 3.6 kB  00:00:00
db                                                                                               | 2.9 kB  00:00:00
(1/3): db/primary_db                                                                             |  66 kB  00:00:00
(2/3): centos/group_gz                                                                           | 153 kB  00:00:00
(3/3): centos/primary_db                                                                         | 3.3 MB  00:00:00
repo id                                                  repo name                                                status
centos                                                   centos                                                   4,070
db                                                       db                                                          91
repolist: 4,161
[root@node1 ~]#

[root@node2 ~]# rm -rf /etc/yum.repos.d/*

[root@node3 ~]# rm -rf /etc/yum.repos.d/*

[root@node1 ~]# scp /etc/yum.repos.d/* node2:/etc/yum.repos.d/
ftp.repo                                                                              100%   67     5.7KB/s   00:00
[root@node1 ~]# scp /etc/yum.repos.d/* node3:/etc/yum.repos.d/
ftp.repo                                                                              100%   67    25.6KB/s   00:00
[root@node1 ~]#

修改从节点yum源

[root@node2 ~]# cat /etc/yum.repos.d/ftp.repo
[db]
name=db
baseurl=ftp://node1/mariadb-repo
gpgcheck=0
enabled=1
[centos]
name=centos
baseurl=ftp://node1/centos
gpgcheck=0
enabled=1
[root@node2 ~]# yum clean all;yum repolist
Loaded plugins: fastestmirror
Cleaning repos: centos db
Cleaning up list of fastest mirrors
Other repos take up 195 M of disk space (use --verbose for details)
Loaded plugins: fastestmirror
Determining fastest mirrors
centos                                                                                           | 3.6 kB  00:00:00
db                                                                                               | 2.9 kB  00:00:00
(1/3): centos/group_gz                                                                           | 153 kB  00:00:00
(2/3): db/primary_db                                                                             |  66 kB  00:00:00
(3/3): centos/primary_db                                                                         | 3.3 MB  00:00:00
repo id                                                  repo name                                                status
centos                                                   centos                                                   4,070
db                                                       db                                                          91
repolist: 4,161
[root@node2 ~]#

[root@node3 ~]# cat /etc/yum.repos.d/ftp.repo
[db]
name=db
baseurl=ftp://node1/mariadb-repo
gpgcheck=0
enabled=1
[centos]
name=centos
baseurl=ftp://node1/centos
gpgcheck=0
enabled=1
[root@node3 ~]# yum clean all;yum repolist
Loaded plugins: fastestmirror
Cleaning repos: centos db
Cleaning up list of fastest mirrors
Other repos take up 195 M of disk space (use --verbose for details)
Loaded plugins: fastestmirror
Determining fastest mirrors
centos                                                                                           | 3.6 kB  00:00:00
db                                                                                               | 2.9 kB  00:00:00
(1/3): centos/group_gz                                                                           | 153 kB  00:00:00
(2/3): centos/primary_db                                                                         | 3.3 MB  00:00:00
(3/3): db/primary_db                                                                             |  66 kB  00:00:00
repo id                                                  repo name                                                status
centos                                                   centos                                                   4,070
db                                                       db                                                          91
repolist: 4,161
[root@node3 ~]#

三台节点安装数据库

yum install -y mariadb-server

三台节点启动

systemctl start mariadb

三台节点设置密码

mysqladmin -uroot password 123456

三台节点关闭数据库服务

systemctl stop mariadb

三台节点修改配置文件

[root@node3 ~]# cat /etc/my.cnf.d/server.cnf
[server]
[mysqld]
[galera]
wsrep_on=ON
wsrep_provider=/usr/lib64/galera/libgalera_smm.so
wsrep_cluster_address="gcomm://node1,node2,node3"
binlog_format=row
default_storage_engine=InnoDB
innodb_autoinc_lock_mode=2
bind-address=0.0.0.0
wsrep_slave_threads=1
innodb_flush_log_at_trx_commit=0
[embedded]
[mariadb]
[mariadb-10.3]

node1节点启动高可用数据库

[root@node1 ~]# galera_new_cluster

从节点启动数据库

[root@node2 ~]# systemctl restart mariadb

[root@node3 ~]# systemctl restart mariadb

验证

[root@node1 ~]# mysql -uroot -p123456

MariaDB [(none)]> show status like "wsrep_ready";
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| wsrep_ready   | ON    |
+---------------+-------+
1 row in set (0.001 sec)

MariaDB [(none)]> show status like "wsrep_cluster_size";
+--------------------+-------+
| Variable_name      | Value |
+--------------------+-------+
| wsrep_cluster_size | 3     |
+--------------------+-------+
1 row in set (0.000 sec)

MariaDB [(none)]>