MHA高可用群集架构配置实验

一、MHA概述

• 日本DeNA公司youshimaton（现就职于Facebook公司）开发
• 一套优秀的作为MySQL高可用性环境下故障切换和主从提升的高可用软件
• 由MHA Manager（管理节点）和MHA Node（数据节点）组成

二、实验步骤

1、部署MHA架构
1）数据库安装
2）一主两从
3）MHA搭建

2、故障模拟并验证
1）主库失效
2）备选主库成为主库，实现高可用

三、MHA架构部署

3.1、实验环境

在vmware虚拟机中开4台服务器，4台均为Centos7版本

修改4台服务器主机名并在4台服务器上添加ip和主机名对应关系。

hostnamectl set-hostname manager         ####修改每台主机名
su
hostnamectl set-hostname master
su
hostnamectl set-hostname slave1
su
hostnamectl set-hostname slave2
su

vim /etc/hosts              ##添加映射
192.168.5.201    manager
192.168.5.203	 master
192.168.5.204    slave1
192.168.5.205    slave2

3.2、安装数据库

• 需要在节点服务器master和两个slave服务器上安装mysql。

• 安装方法可以参考我前面的博客，点此跳~~~~~~

3.3、配置一主两从

• 修改三台节点服务器mysql 的主配置文件/etc/my.cnf，注意三台服务器的 server-id 不能一样

---配置主服务器：
vim /etc/my.cnf
[mysql]
server-id = 1
#开启二进制日志
log_bin = master-bin
#允许从服务器进行同步
log-slave-updates = true

---配置从服务器slave1：
vim /etc/my.cnf
[mysql]
server-id = 2
#开启二进制日志
log_bin = master-bin
 #使用中继日志进行同步
relay-log = relay-log-bin
relay-log-index = slave-relay-bin.index

---配置从服务器slave2：
vim /etc/my.cnf
[mysql]
server-id = 3
log_bin = master-bin
relay-log = relay-log-bin
relay-log-index = slave-relay-bin.index

• 关闭防火墙，启动数据库

#在三台服务器上分别创建这两个个软链接
ln -s /usr/local/mysql/bin/mysql /usr/sbin/
ln -s /usr/local/mysql/bin/mysqlbinlog /usr/sbin/

#启动mysql
/usr/local/mysql/bin/mysqld_safe --user=mysql &

#关闭防火墙和安全功能
systemctl stop firewalld.service
setenforce 0

• 数据库用户权限配置
• 三台节点服务器都开启以下权限

mysql -uroot  -pabc123     ###进入数据库，密码是之前设置的”abc123“

mysql> grant replication slave on *.* to 'myslave'@'192.168.5.%' identified by '123';
###允许从服务器使用myslave这个用户名去复制主服务器数据

mysql> grant all privileges on *.* to 'mha'@'192.168.5.%' identified by 'manager';
###允许manager服务器使用mha这个用户名的所有权限

mysql> flush privileges;   ##刷新

####下面三条授权按理论是不用添加的，但是做案例实验环境时候通过 MHA 检查MySQL 主从有报错，报两个从库通过主机名连接不上主库，所以所有数据库加上下面的授权。

mysql> grant all privileges on *.* to 'mha'@'master' identified by 'manager';
mysql> grant all privileges on *.* to 'mha'@'slave1' identified by 'manager';
mysql> grant all privileges on *.* to 'mha'@'slave2' identified by 'manager';

• 在 master服务器上查看二进制文件和同步点

mysql> show master status;
+-------------------+----------+--------------+------------------+-------------------+
| File              | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+-------------------+----------+--------------+------------------+-------------------+
| master-bin.000001 |      154 |              |                  |                   |
+-------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

• 接下来在 slave1和 slave2服务器上 分别执行同步并设置两个从库为只读模式

mysql> change master to master_host='192.168.5.203',master_user='myslave',master_password='123',master_log_file='master-bin.000001',master_log_pos=154; 
mysql> start slave;   ###开启同步
mysql> set global read_only=1;   ###设置为为只读模式

3.4、搭建MHA

• 关闭4台服务器的防火墙

systemctl stop firewalld.service 
setenforce 0

• 在4台服务器上都安装 MHA 依赖的环境，首先安装 epel 源。

yum install epel-release --nogpgcheck
yum install -y perl-DBD-MySQL \
perl-Config-Tiny \
perl-Log-Dispatch \
perl-Parallel-ForkManager \
perl-ExtUtils-CBuilder \
perl-ExtUtils-MakeMaker \
perl-CPAN

• 在4台服务器上都安装node 组件（我这边用的Centos7.4，所以用node0.57版本），
  下面是在master服务器上演示安装node，实际4台都要安装。

[root@master ~]# mkdir /abc 
[root@master ~]# mount.cifs //192.168.1.109/MHA /abc  ##将真机的文件夹共享过来
[root@master ~]# cd /abc/mha/
[root@master mha]# tar zxvf mha4mysql-node-0.57.tar.gz -C /opt
[root@master mha]# cd /opt/mha4mysql-node-0.57/
[root@master mha4mysql-node-0.57]# perl Makefile.PL 
[root@master mha4mysql-node-0.57]# make & make install

• 在 MHA-manager 上安装 manager 组件（！注意：一定要先安装node 组件才能安装manager 组件）

[root@manager mha]# cd /abc/mha/
[root@manager mha]# ls
cmake-2.8.6.tar.gz             mha4mysql-node-0.57.tar.gz  ruby-2.4.1.tar.gz
mha4mysql-manager-0.57.tar.gz  mysql-5.6.36.tar.gz         ruby安装.png
[root@manager mha]# tar zxvf mha4mysql-manager-0.57.tar.gz -C /opt
[root@manager mha]# cd /opt/mha4mysql-manager-0.57/
[root@manager mha4mysql-manager-0.57]# perl Makefile.PL 
[root@manager mha4mysql-manager-0.57]# make & make install

• manager 和node安装后在/usr/local/bin 下面会生成几个工具，主要包括以下几个

[root@manager mha4mysql-manager-0.57]# cd /usr/local/bin 
[root@manager bin]# ls
masterha_check_ssh 检查 MHA 的 SSH 配置状况
masterha_check_repl 检查 MySQL 复制状况
masterha_manger 启动 manager的脚本
masterha_check_status 检测当前 MHA 运行状态
masterha_master_monitor 检测 master 是否宕机
masterha_master_switch 控制故障转移（自动或者手动）
masterha_conf_host 添加或删除配置的 server 信息
masterha_stop  关闭manager
save_binary_logs 保存和复制 master 的二进制日志
apply_diff_relay_logs 识别差异的中继日志事件并将其差异的事件应用于其他的 slave
filter_mysqlbinlog 去除不必要的 ROLLBACK 事件（MHA 已不再使用这个工具）
purge_relay_logs 清除中继日志（不会阻塞 SQL 线程）

• 为4台服务器配置ssh无密码认证
• 在 manager 上配置到所有数据库节点的无密码认证

[root@manager ~]# ssh-keygen -t rsa //一路按回车键
[root@manager ~]# ssh-copy-id 192.168.5.203   ##需要输入终端登录密码
[root@manager ~]# ssh-copy-id 192.168.5.204
[root@manager ~]# ssh-copy-id 192.168.5.205

• 在 master 上配置到数据库节点slave1和slave2的无密码认证

[root@master ~]# ssh-keygen -t rsa
[root@master ~]# ssh-copy-id 192.168.5.204
[root@master ~]# ssh-copy-id 192.168.5.205

• 在 slave1上配置到数据库节点master和slave2的无密码认证

[root@slave1  ~]# ssh-keygen -t rsa
[root@slave1  ~]# ssh-copy-id 192.168.5.203
[root@slave1  ~]# ssh-copy-id 192.168.5.205

• 在 slave2上配置到数据库节点master和slave2的无密码认证

[root@slave2 ~]# ssh-keygen -t rsa
[root@slave2  ~]# ssh-copy-id 192.168.5.203
[root@slave2  ~]# ssh-copy-id 192.168.5.204

• 修改MHA配置文件，在manager 服务器上复制相关脚本到/usr/local/bin 目录

[root@manager ~]# cp -ra /opt/mha4mysql-manager-0.57/samples/scripts /usr/local/bin
//拷贝后会有四个执行文件
[root@atlas ~]# ll /usr/local/bin/scripts/
总用量 32
-rwxr-xr-x 1 mysql mysql 3648 5 月 31 2015 master_ip_failover  #自动切换时 VIP 管理的脚本
-rwxr-xr-x 1 mysql mysql 9872 5 月 25 09:07 master_ip_online_change #在线切换时 vip 的管理
-rwxr-xr-x 1 mysql mysql 11867 5 月 31 2015 power_manager #故障发生后关闭主机的脚本
-rwxr-xr-x 1 mysql mysql 1360 5 月 31 2015 send_report #因故障切换后发送报警的脚本

• 复制上述的自动切换时 VIP 管理的脚本到/usr/local/bin 目录，这里使用脚本管理 VIP

[root@manager ~]# cp /usr/local/bin/scripts/master_ip_failover /usr/local/bin

修改内容如下：（删除原有内容，输入以下内容）

[root@manager ~]# vim /usr/local/bin/master_ip_failover
#!/usr/bin/env perl
use strict;
use warnings FATAL => 'all';
use Getopt::Long;
my (
$command, $ssh_user, $orig_master_host, $orig_master_ip,
$orig_master_port, $new_master_host, $new_master_ip, $new_master_port
);

my $vip = '192.168.5.200';
my $brdc = '192.168.5.255';
my $ifdev = 'ens33';
my $key = '1';
my $ssh_start_vip = "/sbin/ifconfig ens33:$key $vip";
my $ssh_stop_vip = "/sbin/ifconfig ens33:$key down";
my $exit_code = 0;
#my $ssh_start_vip = "/usr/sbin/ip addr add $vip/24 brd $brdc dev $ifdev label $ifdev:$key;/usr/sbin/arping -q -A -c 1 -I $ifdev $vip;iptables -F;";
#my $ssh_stop_vip = "/usr/sbin/ip addr del $vip/24 dev $ifdev label $ifdev:$key";

GetOptions(
'command=s' => \$command,
'ssh_user=s' => \$ssh_user,
'orig_master_host=s' => \$orig_master_host,
'orig_master_ip=s' => \$orig_master_ip,
'orig_master_port=i' => \$orig_master_port,
'new_master_host=s' => \$new_master_host,
'new_master_ip=s' => \$new_master_ip,
'new_master_port=i' => \$new_master_port,
);

exit &main();

sub main {

print "\n\nIN SCRIPT TEST====$ssh_stop_vip==$ssh_start_vip===\n\n";

if ( $command eq "stop" || $command eq "stopssh" ) {

my $exit_code = 1;
eval {
print "Disabling the VIP on old master: $orig_master_host \n";
&stop_vip();
$exit_code = 0;
};
if ($@) {
warn "Got Error: $@\n";
exit $exit_code;
}
exit $exit_code;
}
elsif ( $command eq "start" ) {

my $exit_code = 10;
eval {
print "Enabling the VIP - $vip on the new master - $new_master_host \n";
&start_vip();
$exit_code = 0;
};
if ($@) {
warn $@;
exit $exit_code;
}
exit $exit_code;
}
elsif ( $command eq "status" ) {
print "Checking the Status of the script.. OK \n";
exit 0;
}
else {
&usage();
exit 1;
}
}
sub start_vip() {
`ssh $ssh_user\@$new_master_host \" $ssh_start_vip \"`;
}
# A simple system call that disable the VIP on the old_master
sub stop_vip() {
`ssh $ssh_user\@$orig_master_host \" $ssh_stop_vip \"`;
}

sub usage {
print
"Usage: master_ip_failover --command=start|stop|stopssh|status --orig_master_host=host --orig_master_ip=ip --orig_master_port=port --new_master_host=host --new_master_ip=ip --new_master_port=port\n";
}

• 由于是直接复制的，需要输入“% s/^#//g”命令将多余的#号去掉

• 别忘了在第一行加上#号

• 创建 MHA 软件目录并拷贝配置文件。

[root@manager ~]# mkdir /etc/masterha
[root@manager ~]# cp /opt/mha4mysql-manager-0.57/samples/conf/app1.cnf /etc/masterha/
[root@manager ~]# vim /etc/masterha/app1.cnf

[server default]
manager_log=/var/log/masterha/app1/manager.log
manager_workdir=/var/log/masterha/app1
master_binlog_dir=/usr/local/mysql/data
master_ip_failover_script=/usr/local/bin/master_ip_failover
master_ip_online_change_script=/usr/local/bin/master_ip_online_change
password=manager
ping_interval=1
remote_workdir=/tmp
repl_password=123
repl_user=myslave
secondary_check_script=/usr/local/bin/masterha_secondary_check -s 192.168.5.204 -s 192.168.5.205
shutdown_script=""
ssh_user=root
user=mha

[server1]
hostname=192.168.5.203
port=3306

[server2]
candidate_master=1
check_repl_delay=0
hostname=192.168.5.204
port=3306

[server3]
hostname=192.168.5.205
port=3306

• 测试 ssh 无密码认证，如果正常最后会输出 successfully，如下所示

[root@manager ~]# masterha_check_ssh -conf=/etc/masterha/app1.cnf
Sat Feb  8 10:28:09 2020 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping.
Sat Feb  8 10:28:09 2020 - [info] Reading application default configuration from /etc/masterha/app1.cnf..
Sat Feb  8 10:28:09 2020 - [info] Reading server configuration from /etc/masterha/app1.cnf..
Sat Feb  8 10:28:09 2020 - [info] Starting SSH connection tests..
Sat Feb  8 10:28:12 2020 - [debug] 
Sat Feb  8 10:28:10 2020 - [debug]  Connecting via SSH from [email protected](192.168.5.204:22) to [email protected](192.168.5.203:22)..
Sat Feb  8 10:28:11 2020 - [debug]   ok.
Sat Feb  8 10:28:11 2020 - [debug]  Connecting via SSH from [email protected](192.168.5.204:22) to [email protected](192.168.5.205:22)..
Sat Feb  8 10:28:11 2020 - [debug]   ok.
Sat Feb  8 10:28:12 2020 - [debug] 
Sat Feb  8 10:28:09 2020 - [debug]  Connecting via SSH from [email protected](192.168.5.203:22) to [email protected](192.168.5.204:22)..
Sat Feb  8 10:28:10 2020 - [debug]   ok.
Sat Feb  8 10:28:10 2020 - [debug]  Connecting via SSH from [email protected](192.168.5.203:22) to [email protected](192.168.5.205:22)..
Sat Feb  8 10:28:11 2020 - [debug]   ok.
Sat Feb  8 10:28:13 2020 - [debug] 
Sat Feb  8 10:28:10 2020 - [debug]  Connecting via SSH from [email protected](192.168.5.205:22) to [email protected](192.168.5.203:22)..
Sat Feb  8 10:28:11 2020 - [debug]   ok.
Sat Feb  8 10:28:11 2020 - [debug]  Connecting via SSH from [email protected](192.168.5.205:22) to [email protected](192.168.5.204:22)..
Sat Feb  8 10:28:12 2020 - [debug]   ok.
Sat Feb  8 10:28:13 2020 - [info] All SSH connection tests passed successfully.

• 测试健康状态

[root@manager bin]# masterha_check_repl -conf=/etc/masterha/app1.cnf
Sat Feb  8 10:31:56 2020 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping.
Sat Feb  8 10:31:56 2020 - [info] Reading application default configuration from /etc/masterha/app1.cnf..
Sat Feb  8 10:31:56 2020 - [info] Reading server configuration from /etc/masterha/app1.cnf..
Sat Feb  8 10:31:56 2020 - [info] MHA::MasterMonitor version 0.57.
Sat Feb  8 10:31:58 2020 - [info] GTID failover mode = 0
Sat Feb  8 10:31:58 2020 - [info] Dead Servers:
Sat Feb  8 10:31:58 2020 - [info] Alive Servers:
Sat Feb  8 10:31:58 2020 - [info]   192.168.5.203(192.168.5.203:3306)
Sat Feb  8 10:31:58 2020 - [info]   192.168.5.204(192.168.5.204:3306)
Sat Feb  8 10:31:58 2020 - [info]   192.168.5.205(192.168.5.205:3306)
Sat Feb  8 10:31:58 2020 - [info] Alive Slaves:
Sat Feb  8 10:31:58 2020 - [info]   192.168.5.204(192.168.5.204:3306)  Version=5.6.26-log (oldest major version between slaves) log-bin:enabled
Sat Feb  8 10:31:58 2020 - [info]     Replicating from 192.168.5.203(192.168.5.203:3306)
Sat Feb  8 10:31:58 2020 - [info]     Primary candidate for the new Master (candidate_master is set)
Sat Feb  8 10:31:58 2020 - [info]   192.168.5.205(192.168.5.205:3306)  Version=5.6.26-log (oldest major version between slaves) log-bin:enabled
Sat Feb  8 10:31:58 2020 - [info]     Replicating from 192.168.5.203(192.168.5.203:3306)
Sat Feb  8 10:31:58 2020 - [info] Current Alive Master: 192.168.5.203(192.168.5.203:3306)
Sat Feb  8 10:31:58 2020 - [info] Checking slave configurations..
Sat Feb  8 10:31:58 2020 - [warning]  relay_log_purge=0 is not set on slave 192.168.5.204(192.168.5.204:3306).
Sat Feb  8 10:31:58 2020 - [warning]  relay_log_purge=0 is not set on slave 192.168.5.205(192.168.5.205:3306).
Sat Feb  8 10:31:58 2020 - [info] Checking replication filtering settings..
Sat Feb  8 10:31:58 2020 - [info]  binlog_do_db= , binlog_ignore_db= 
Sat Feb  8 10:31:58 2020 - [info]  Replication filtering check ok.
Sat Feb  8 10:31:58 2020 - [info] GTID (with auto-pos) is not supported
Sat Feb  8 10:31:58 2020 - [info] Starting SSH connection tests..
Sat Feb  8 10:32:01 2020 - [info] All SSH connection tests passed successfully.
Sat Feb  8 10:32:01 2020 - [info] Checking MHA Node version..
Sat Feb  8 10:32:02 2020 - [info]  Version check ok.
Sat Feb  8 10:32:02 2020 - [info] Checking SSH publickey authentication settings on the current master..
Sat Feb  8 10:32:02 2020 - [info] HealthCheck: SSH to 192.168.5.203 is reachable.
Sat Feb  8 10:32:03 2020 - [info] Master MHA Node version is 0.57.
Sat Feb  8 10:32:03 2020 - [info] Checking recovery script configurations on 192.168.5.203(192.168.5.203:3306)..
Sat Feb  8 10:32:03 2020 - [info]   Executing command: save_binary_logs --command=test --start_pos=4 --binlog_dir=/usr/local/mysql/data --output_file=/tmp/save_binary_logs_test --manager_version=0.57 --start_file=master-bin.000001 
Sat Feb  8 10:32:03 2020 - [info]   Connecting to [email protected](192.168.5.203:22).. 
  Creating /tmp if not exists..    ok.
  Checking output directory is accessible or not..
   ok.
  Binlog found at /usr/local/mysql/data, up to master-bin.000001
Sat Feb  8 10:32:03 2020 - [info] Binlog setting check done.
Sat Feb  8 10:32:03 2020 - [info] Checking SSH publickey authentication and checking recovery script configurations on all alive slave servers..
Sat Feb  8 10:32:03 2020 - [info]   Executing command : apply_diff_relay_logs --command=test --slave_user='mha' --slave_host=192.168.5.204 --slave_ip=192.168.5.204 --slave_port=3306 --workdir=/tmp --target_version=5.6.26-log --manager_version=0.57 --relay_log_info=/home/mysql/relay-log.info  --relay_dir=/home/mysql/  --slave_pass=xxx
Sat Feb  8 10:32:03 2020 - [info]   Connecting to [email protected](192.168.5.204:22).. 
  Checking slave recovery environment settings..
    Opening /home/mysql/relay-log.info ... ok.
    Relay log found at /home/mysql, up to relay-log-bin.000001
    Temporary relay log file is /home/mysql/relay-log-bin.000001
    Testing mysql connection and privileges..Warning: Using a password on the command line interface can be insecure.
 done.
    Testing mysqlbinlog output.. done.
    Cleaning up test file(s).. done.
Sat Feb  8 10:32:18 2020 - [info]   Executing command : apply_diff_relay_logs --command=test --slave_user='mha' --slave_host=192.168.5.205 --slave_ip=192.168.5.205 --slave_port=3306 --workdir=/tmp --target_version=5.6.26-log --manager_version=0.57 --relay_log_info=/home/mysql/relay-log.info  --relay_dir=/home/mysql/  --slave_pass=xxx
Sat Feb  8 10:32:18 2020 - [info]   Connecting to [email protected](192.168.5.205:22).. 
  Checking slave recovery environment settings..
    Opening /home/mysql/relay-log.info ... ok.
    Relay log found at /home/mysql, up to relay-log-bin.000001
    Temporary relay log file is /home/mysql/relay-log-bin.000001
    Testing mysql connection and privileges..Warning: Using a password on the command line interface can be insecure.
 done.
    Testing mysqlbinlog output.. done.
    Cleaning up test file(s).. done.
Sat Feb  8 10:32:34 2020 - [info] Slaves settings check done.
Sat Feb  8 10:32:34 2020 - [info] 
192.168.5.203(192.168.5.203:3306) (current master)
 +--192.168.5.204(192.168.5.204:3306)
 +--192.168.5.205(192.168.5.205:3306)

Sat Feb  8 10:32:34 2020 - [info] Checking replication health on 192.168.5.204..
Sat Feb  8 10:32:34 2020 - [info]  ok.
Sat Feb  8 10:32:34 2020 - [info] Checking replication health on 192.168.5.205..
Sat Feb  8 10:32:34 2020 - [info]  ok.
Sat Feb  8 10:32:34 2020 - [info] Checking master_ip_failover_script status:
Sat Feb  8 10:32:34 2020 - [info]   /usr/local/bin/master_ip_failover --command=status --ssh_user=root --orig_master_host=192.168.5.203 --orig_master_ip=192.168.5.203 --orig_master_port=3306 


IN SCRIPT TEST====/sbin/ifconfig ens33:1 down==/sbin/ifconfig ens33:1 192.168.5.200===

Checking the Status of the script.. OK 
Sat Feb  8 10:32:34 2020 - [info]  OK.
Sat Feb  8 10:32:34 2020 - [warning] shutdown_script is not defined.
Sat Feb  8 10:32:34 2020 - [info] Got exit code 0 (Not master dead).

MySQL Replication Health is OK.

• //注意：第一次配置需要去master服务器上手动开启虚拟IP

[root@master ~]# /sbin/ifconfig ens33:1 192.168.5.200/24

• 启动 MHA，查看当前MHA状态

[root@manager ~]#  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 &
[1] 129929     ####已启动

[root@manager ~]# masterha_check_status --conf=/etc/masterha/app1.cnf
app1 (pid:10832) is running(0:PING_OK), master:192.168.5.203
        ###可以看见当前的master是5.203master节点服务器

四、验证MHA架构

• 在master节点服务器上模拟宕掉服务器

[root@master ~]# pkill -9 mysql   

• 在manager服务器上查看MHA状态

[root@manager ~]# masterha_check_status -conf=/etc/masterha/app1.cnf
app1 (pid:36150) is running(0:PING_OK), master:192.168.5.204
                         ###可以看见master已经变为5.204slave1节点服务器

• 并且虚拟的IP会漂移到slave1服务器上，不影响此架构的主从复制功能。

[root@slave1 ~]# ifconfig
ens33:1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.5.200  netmask 255.255.255.0  broadcast 192.168.5.255
        ether 00:0c:29:34:57:c1  txqueuelen 1000  (Ethernet)