linux——mysql的高可用MHA

        从宕机崩溃的master 保存二进制日志事件（binlog events）；
        识别含有最新的更新slave日志
        应用差异的中继日志（relay log）到其他的slave
        应用从master保存的二进制日志事件
        提升一个slave为新的master
        使其他的slave连接新的master进行复制

二、案例

        192.168.100.3    manager（MHA）         mgt
        192.168.100.4    master                                master
        192.168.100.5    slave                               slave1
        192.168.100.6    slave                              slave2

三、构建MHA

一、基础环境

关闭防火墙

设置selinux宽容模式

配置静态IP

                    192.168.100.3    manager（MHA）         mgt
                    192.168.100.4    master                                master
                    192.168.100.5    slave                               slave1
                    192.168.100.6    slave                              slave2

修改主机名

                    192.168.100.3                                        mgt
                    192.168.100.4                                 master
                    192.168.100.5                                 slave1
                    192.168.100.6                                slave2

二、ssh免密登录

        192.168.100.3
                   ssh-keygen
                   for i in 4 5 6;do ssh-copy-id [email protected].$i;done

          192.168.100.4
                   ssh-keygen
                   for i in 3 5 6;do ssh-copy-id [email protected].$i;done

         192.168.100.5
                   ssh-keygen
                   for i in 4 3 6;do ssh-copy-id [email protected].$i;done

         192.168.100.6
                   ssh-keygen
                   for i in 4 5 3;do ssh-copy-id [email protected].$i;done

所有节点配置hosts

vim /etc/hosts

                     for i in 4 5 6 ;do scp/etc/hosts 192.168.100.$i:/etc;done
                   192.168.100.3   mgt
                   192.168.100.4   master
                   192.168.100.5   slave1
                   192.168.100.6   slave2

测试
for i in 3 4 5;do ssh 192.168.100.$i ;done （在192.168.100.3测试）

for i in master slave1 slave2;do ssh $i ;done

三、主从复制

master

vim /etc/my.cnf
[mysqld]
server-id = 1
log-bin = master-bin
log-slave-updates = true

ystemctl restart mariadb
mysql -e "grant replication slave on *.* to 'myslave'@'192.168.100.%' identified by '123.com';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.100.%' identified by '123.com';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.100.3' identified by '123.com';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.100.5' identified by '123.com';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.100.6' identified by '123.com';"
mysql -e "show master status";

slave1

server-id=2
log-bin=master-bin
relay-log=relay-log-bin
relay-log-index=relay-log-bin.index

mysql -e "grant replication slave on *.* to 'myslave'@'192.168.100.%' identified by '123.com';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.100.%' identified by '123.com';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.100.3' identified by '123.com';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.100.4' identified by '123.com';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.100.6' identified by '123.com';"
mysql -e "change master to master_host='192.168.100.4',master_user='myslave',master_password='123.com',master_log_file='master-bin.000003',master_log_pos=1007;"

mysql -e “slave start”

slave2

server-id=3
log-bin=master-bin
relay-log=relay-log-bin
relay-log-index=relay-log-bin.index

mysql -e "grant replication slave on *.* to 'myslave'@'192.168.100.%' identified by '123.com';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.100.%' identified by '123.com';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.100.3' identified by '123.com';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.100.4' identified by '123.com';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.100.5' identified by '123.com';"
mysql -e "change master to master_host='192.168.100.4',master_user='myslave',master_password='123.com',master_log_file='master-bin.000003',master_log_pos=1007;"

mysql -e “slave start”

四、MHA安装

一、环境

所有节点安装perl环境

yum install epel-release -y &&yum install epel-release -y（第二次是更新）
yum -y install perl-DBD-MySQL perl-ExtUtils-MakeMaker perl-Config-Tiny perl-Log-Dispatch perl-Parallel-ForkManager perl-Time-HiRes perl-CPAN

二、安装node

所有节点安装node(已经下载的源码包）

tar xf mha4mysql-node-0.57.tar.gz
cd mha4mysql-node-0.57
perl Makefile.PL && make && make install

cd /usr/local/bin （发现存在文件）

yum install epel-release -y && yum install epel-release -y && yum -y install perl-DBD-MySQL perl-ExtUtils-MakeMaker perl-Config-Tiny perl-Log-Dispatch perl-Parallel-ForkManager perl-Time-HiRes perl-CPAN&&tar xf mha4mysql-node-0.57.tar.gz && cd mha4mysql-node-0.57 && perl Makefile.PL && make && make install && cd /usr/local/bin && ls

三、安装manager

tar xf mha4mysql-manager-0.57.tar.gz
cd /root/mha4mysql-manager-0.57
perl Makefile.PL && make && make install
cp sample/scripts/master_ip_failover /usr/local/bin/
cp sample/scripts/master_ip_online_change /usr/local/bin/

cd /usr/local/bin

vim master_ip_failover

        脚本说明(master_ip_failover)
           master_ip_failover   自动切换时 VIP 管理的脚本
           master_ip_online_change   在线切换时 vip 的管理
           power_manager   故障发生后关闭主机的脚本
           send_report   因故障切换后发送报警的脚本

配置文件建立
mkdir /etc/masterha
vim /etc/masterha/app1.cnf

mkdir /var/log/masterha/app1

测试MHA

masterha_check_ssh --conf=/etc/masterha/app1.cnf
masterha_check_repl --conf=/etc/masterha/app1.cnf

启动

nohup masterha_manager --conf=/etc/masterha/app1.cnf --remove_dead_master_conf --ignore_last_failover < /dev/null > /var/log/masterha/app1/manager.log 2>&1 &