架构师学习-mysql-mha高可用架构（九十九）

注意：mha-manager暂时不支持centos8版本，避免踩坑
注意：mha-manager暂时不支持centos8版本，避免踩坑
注意：mha-manager暂时不支持centos8版本，避免踩坑

1、准备4台服务器，3台安装mysql，并且1主2从

2、四台服务器设置免密登录

1. 在四台服务器都执行以下命令

ssh-keygen -t rsa

2. 在3台安装了mysql服务的机器上都执行以下命令，将公钥拷贝到mha-manager服务器

ssh-copy-id 192.168.220.131

3. 在mha-manager服务器执行以下命令查看公钥

cat /root/.ssh/authorized_keys

4. 将mha-manager机器的公钥也拷贝到之前的文件

cat /root/.ssh/id_rsa.pub >> /root/.ssh/authorized_keys

5. 从mha-manager的机器执行以下命令将公钥拷贝到其他三台机器

scp /root/.ssh/authorized_keys root@192.168.220.128:/root/.ssh/authorized_keys
scp /root/.ssh/authorized_keys root@192.168.220.129:/root/.ssh/authorized_keys
scp /root/.ssh/authorized_keys root@192.168.220.130:/root/.ssh/authorized_keys

6. 在mha-manager机器执行以下命令查看是否与其他三台服务器互通

ssh 192.168.220.128
exit
ssh 192.168.220.129
exit
ssh 192.168.220.130
exit

3、安装mha

mha-manager（mha-manager的机器）：https://github.com/yoshinorim/mha4mysql-manager/releases/tag/v0.58
mha-node（3台mysql的机器）：https://github.com/yoshinorim/mha4mysql-node/releases/tag/v0.58

1. 在四台服务器安装mha-node

yum install perl-DBD-MySQL -y

wget https://github.com/yoshinorim/mha4mysql-node/releases/download/v0.58/mha4mysql-node-0.58-0.el7.centos.noarch.rpm

rpm -ivh mha4mysql-node-0.58-0.el7.centos.noarch.rpm

2. 在mha-manager机器安装mha-manager

wget http://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm

rpm -ivh epel-release-latest-7.noarch.rpm

yum install perl-DBD-MySQL perl-Config-Tiny perl-Log-Dispatch perl-Parallel-ForkManager -y

wget https://github.com/yoshinorim/mha4mysql-manager/releases/download/v0.58/mha4mysql-manager-0.58-0.el7.centos.noarch.rpm

rpm -ivh mha4mysql-manager-0.58-0.el7.centos.noarch.rpm

4、mha配置

1. 初始化配置目录

mkdir -p /var/log/mha/app1

touch /var/log/mha/app1/manager.log

2. 配置全局监控配置文件

在三台mysql库下执行以下命令

create user 'mha'@'%' identified with mysql_native_password by '123456';

grant all privileges on *.* to 'mha'@'%' with grant option;
flush privileges;

vim /etc/masterha_default.cnf

[server default]

user=mha
password=123456
port=3306
ssh_user=root
repl_user=root
repl_password=123456
port=3306
ping_interval=1
secondary_check_script=masterha_secondary_check -s 192.168.220.128 -s 192.168.220.129 -s 192.168.220.130

3. 配置监控实例配置文件

mkdir -p /etc/mha

vim /etc/mha/app1.cnf

[server default]

manager_workdir=/var/log/mha/app1
manager_log=/var/log/mha/app1/manager.log

[server1]
hostname=192.168.220.128
candidate_master=1
master_binlog_dir="/usr/local/mysql/data"

[server2]
hostname=192.168.220.129
candidate_master=1
master_binlog_dir="/usr/local/mysql/data"

[server3]
hostname=192.168.220.130
candidate_master=1
master_binlog_dir="/usr/local/mysql/data"

4. 在三台mysql库配置mysqlbinlog软连接

ln -s /usr/local/mysql/bin/mysqlbinlog  /usr/local/bin/mysqlbinlog

5. 在三台mysql库配置mysql软连接

ln -s /usr/local/mysql/bin/mysql  /usr/local/bin/mysql

5、mha配置检测

1. ssh通信检测

masterha_check_ssh --conf=/etc/mha/app1.cnf

2. mysql主从复制检测

masterha_check_repl --conf=/etc/mha/app1.cnf

3) mha-manager启动

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

masterha_check_status --conf=/etc/mha/app1.cnf

tail -f /var/log/mha/app1/manager.log

6、测试mha故障转移

1. 打开日志

tail -200f /var/log/mha/app1/manager.log

2. 关闭mysql主库服务

service mysql stop

3) 查看mha日志