MySQL 部署 MHA 高可用架构 (二)

实现 MHA VIP 功能

配置 master_ip_failover 脚本(db3)

把 master_ip_failover 上传到 /iba/software 上

master_ip_failover 文件内容

``` #!/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 = '192.168.31.88/24';
my $key = '1';
my $ssh_start_vip = "/sbin/ifconfig eth0:$key $vip";
my $ssh_stop_vip = "/sbin/ifconfig eth0:$key down";

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 "

IN SCRIPT TEST====$ssh_stop_vip==$ssh_start_vip===

";

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

    my $exit_code = 1;
    eval {
        print "Disabling the VIP on old master: $orig_master_host 
";
        &stop_vip();
        $exit_code = 0;
    };
    if ($@) {
        warn "Got Error: $@
";
        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 
";
        &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 
";
    exit 0;
}
else {
    &usage();
    exit 1;
}

}

sub start_vip() {
ssh $ssh_user@$new_master_host " $ssh_start_vip ";
}
sub stop_vip() {
return 0 unless ($ssh_user);
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 ";
}

</details>

cd /iba/software/
cp /iba/software/master_ip_failover /usr/local/bin/

修改脚本参数，改为自己的VIP，网卡设备

vi /usr/local/bin/master_ip_failover
my $vip = '192.168.31.88/24';
my $ssh_start_vip = "/sbin/ifconfig eth0:$key $vip";
my $ssh_stop_vip = "/sbin/ifconfig eth0:$key down";

修改 mha 配置

vi /etc/mha/app1.cnf

在 [server default] 下添加

master_ip_failover_script=/usr/local/bin/master_ip_failover

yum install dos2unix -y
dos2unix /usr/local/bin/master_ip_failover
chmod +x /usr/local/bin/master_ip_failover

### 在主库上手工生成第一个vip地址

ifconfig eth0:1 192.168.31.88/24

手动停止网卡的方法：ifconfig eth0:1 down

### 重启 MHA manager 使配置生效(db3)

masterha_stop --conf=/etc/mha/app1.cnf
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 &
tail -f /var/log/mha/app1/manager.log

### 测试

停止主库

systemctl stop mysqld

查看 ip, 发现 vip 已经飘走

ip add

在 db3 上执行

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

结果显示 主库现在为 db1 ，经查看，vip 成功切换到 db1 上。

## 实现邮件报警
### 编写发邮件脚本(db3)

在 [server default] 下添加

vi /etc/mha/app1.cnf
report_script=/usr/local/bin/send_report

### 文件/usr/local/bin/send_report 内容

!/usr/bin/python

-- coding: UTF-8 --

import smtplib
from email.mime.text import MIMEText
from email.header import Header

第三方 SMTP 服务

mail_host="smtp.126.com" #设置服务器
mail_user="xxxxx@126.com" #用户名
mail_pass="xxxxx" #口令

sender = 'xxxxx@126.com'
receivers = 'yyyyyy@qq.com' # 接收邮件，可设置为你的QQ邮箱或者其他邮箱

message = MIMEText('MHA master 已经切换, 请查看', 'plain', 'utf-8')
message['From'] = sender
message['To'] = receivers

subject = 'MySQL MHA 邮件'
message['Subject'] = Header(subject, 'utf-8')

try:
smtpObj = smtplib.SMTP()
smtpObj.connect(mail_host, 25) # 25 为 SMTP 端口号
smtpObj.login(mail_user,mail_pass)
smtpObj.sendmail(sender, receivers, message.as_string())
print "邮件发送成功"
except smtplib.SMTPException, e:
print "Error:", evi /usr/local/bin/send_report

### 添加执行权限

chmod + x /usr/local/bin/send_report

### 重启 mha

masterha_stop --conf=/etc/mha/app1.cnf
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 &

### MySQL 主库 down 时，切换成功发送邮件
![](https://img2018.cnblogs.com/blog/1334255/201912/1334255-20191204205056518-872668.png)
### 邮件发送成功