注意：關閉防火墻、selinux

二、準備階段：


step1：建立信任關系：


在Node：10.20.20.12上：


[root@mysqlmaster /]#ssh-keygen -t rsa
[root@mysqlmaster /]#ssh-copy-id -i /root/.ssh/id_rsa.pub root@10.20.20.12
[root@mysqlmaster /]#ssh-copy-id -i /root/.ssh/id_rsa.pub root@10.20.20.13
[root@mysqlmaster /]#ssh-copy-id -i /root/.ssh/id_rsa.pub root@10.20.20.14


在Node：10.20.20.13上：
[root@mysqlslave1 /]#ssh-keygen -t rsa
[root@mysqlslave1 /]#ssh-copy-id -i /root/.ssh/id_rsa.pub root@10.20.20.12
[root@mysqlslave1 /]#ssh-copy-id -i /root/.ssh/id_rsa.pub root@10.20.20.13
[root@mysqlslave1 /]#ssh-copy-id -i /root/.ssh/id_rsa.pub root@10.20.20.14


在Node：10.20.20.14上：
[root@mysqlslave2 /]#ssh-keygen -t rsa
[root@mysqlslave2 /]#ssh-copy-id -i /root/.ssh/id_rsa.pub root@10.20.20.12
[root@mysqlslave2 /]#ssh-copy-id -i /root/.ssh/id_rsa.pub root@10.20.20.13
[root@mysqlslave2 /]#ssh-copy-id -i /root/.ssh/id_rsa.pub root@10.20.20.14
step2：部署mysql服務(源碼搭建)


1、安裝編譯代碼需要的包
yum -y install make gcc-c++ cmake bison-devel  ncurses-devel


2、下載MySQL 5.6.14
wget http://cdn.mysql.com/Downloads/MySQL-5.6/mysql-5.6.27.tar.gz
tar xvf mysql-5.6.17.tar.gz
cd mysql-5.6.27


3、編譯安裝


cmake \
-DCMAKE_INSTALL_PREFIX=/usr/local/mysql \
-DMYSQL_DATADIR=/data/mysql \
-DSYSCONFDIR=/etc \
-DWITH_MYISAM_STORAGE_ENGINE=1 \
-DWITH_INNOBASE_STORAGE_ENGINE=1 \
-DWITH_MEMORY_STORAGE_ENGINE=1 \
-DWITH_READLINE=1 \
-DMYSQL_UNIX_ADDR=/usr/local/mysql/mysql.sock \
-DMYSQL_TCP_PORT=3306 \
-DENABLED_LOCAL_INFILE=1 \
-DWITH_PARTITION_STORAGE_ENGINE=1 \
-DEXTRA_CHARSETS=all \
-DDEFAULT_CHARSET=utf8 \
-DDEFAULT_COLLATION=utf8_general_ci


make && make install


配置MySQL


創建用戶組
groupadd mysql
useradd -g mysql mysql


修改/usr/local/mysql權限


chown -R mysql:mysql /usr/local/mysql
chown -R mysql:mysql /data


配置my.cnf(詳見conf文件)


以下是簡單的my.cnf配置
[root@mysqlmaster /]# cat /etc/my.cnf
[mysqld]
log-bin=mysql-bin
server-id=12
skip-name-resolve


[root@mysqlslave1 ~]# cat /etc/my.cnf
[mysqld]
log-bin=mysql-bin
server-id=13
read-only=1
relay_log_purge=0
skip-name-resolve


[root@mysqlslave2 .ssh]# cat /etc/my.cnf
[mysqld]
log-bin=mysql-bin
server-id=14
read-only=1
relay_log_purge=0
skip-name-resolve


初始化配置
cd /usr/local/mysql


進入安裝路徑，執行初始化配置腳本，創建系統自帶的數據庫和表


scripts/mysql_install_db --basedir=/usr/local/mysql --datadir=/data/mysql --user=mysql


啟動MySQL
cp support-files/mysql.server /etc/init.d/mysql
chkconfig mysql on
service mysql start  


配置環境變量


vi /etc/profile
export PATH=/usr/local/mysql/bin:$PATH


生效環境變量
source /etc/profile


執行下面的命令修改root密碼


mysql -uroot  
mysql> SET PASSWORD = PASSWORD('123456');


若要設置root用戶可以遠程訪問，執行


mysql> GRANT ALL PRIVILEGES ON *.* TO 'root'@'172.16.%' IDENTIFIED BY 'password' WITH GRANT OPTION;




三、創建MySQL主從復制


step1：創建數據庫管理賬號和復制賬號（主庫、備庫 都執行）


grant all privileges on *.* to 'root'@'10.20.20.%' identified by '123456';
grant Replication slave,super on *.* to 'repler'@'10.20.20.%' identified by '123.com';
grant all privileges on *.* to 'root'@'192.168.1.%' identified by '123456';
flush privileges;


step2：建立mysql之間的主從復制
登錄主服務器的mysql，查詢master的狀態
mysql>show master status;
   +------------------+----------+--------------+------------------+
   | File             | Position | Binlog_Do_DB | Binlog_Ignore_DB |
   +------------------+----------+--------------+------------------+
   | mysql-bin.000001 |      308 |              |                  |
   +------------------+----------+--------------+------------------+
配置從服務器Slave


mysql>change master to master_host='10.20.20.12',master_user='repler',master_password='123.com',master_log_file='mysql-bin.000001',master_log_pos=308;  


四、創建軟鏈接和設置從庫為read only


step1：ln -s /usr/local/mysql/bin/* /usr/local/bin/


注意：需要做這個軟連接，否則再執行masterha_check_repl校驗的時候，會報Can't exec "mysqlbinlog": 沒有那個文件或目錄 的錯誤。


step2：所有從服務器上my.cnf里面添加：read-only=1和relay_log_purge=0




五、安裝MHA_Manager




1. 安裝epel源
rpm -Uvh https://dl.fedoraproject.org/pub/epel/epel-release-latest-6.noarch.rpm


yum --disablerepo=epel -y update ca-certificates


2. 安裝依賴包
yum -y install perl-DBD-MySQL perl-Config-Tiny perl-Log-Dispatch  perl-Params-Validate perl-TimeDate perl-ExtUtils-CBuilder perl-ExtUtils-MakeMaker perl-CPAN perl-Parallel-ForkManager perl-Log-Message
yum -y install perl-NTLM.noarch     --如果要發郵件send_report，需要安裝這個包，否則就不發郵件


3、 安裝MHA_Node(MHA_Manager需要)


tar -zxvf mha4mysql-manager-0.57.tar.gz
cd mha4mysql-manager-0.57
perl Makefile.PL
make
make install




tar -zxf Test-Simple-1.001014.tar.gz 
cd Test-Simple-1.001014
perl Makefile.PL 
make 
make install




tar -zxf CPAN-Perl-Releases-2.48.tar.gz 
cd CPAN-Perl-Releases-2.48
perl Makefile.PL 
make
make install




tar -zxf Log-Dispatch-Perl-0.04.tar.gz 


cd Log-Dispatch-Perl-0.04
perl Makefile.PL
make
make install


mkdir /etc/masterha/
mkdir /etc/masterha/scripts
mkdir /masterha/app1 -p








六、安裝MHA_Node(在所有的Mysql服務器上)


1. 安裝epel源
rpm -Uvh https://dl.fedoraproject.org/pub/epel/epel-release-latest-6.noarch.rpm
yum --disablerepo=epel -y update ca-certificates


2. 安裝依賴包
yum -y install perl-DBD-MySQL perl-Config-Tiny perl-Log-Dispatch  perl-Params-Validate perl-TimeDate perl-ExtUtils-CBuilder perl-ExtUtils-MakeMaker perl-CPAN perl-Parallel-ForkManager


3、 安裝MHA_Node
tar -zxf mha4mysql-node-0.57.tar.gz
cd mha4mysql-node-0.57
perl Makefile.PL
make
make install


mkdir /masterha/app1 -p






七、配置MHA_Manager(192.168.1.100)：


vim /etc/masterha/app1.cnf


[server default]
#workdir on the management server
manager_workdir=/masterha/app1/
manager_log=/masterha/app1/manager.log
#workdir on the node for mysql server
remote_workdir=/masterha/app1
master_binlog_dir=/data/mysql
check_repl_delay=0
#mysql user and password
user=root
password=123456
#replication_user
repl_user=repler
repl_password=123.com
#checking master every second
ping_interval=1
#ssh user
ssh_user=root
#檢測master的可用性
secondary_check_script=masterha_secondary_check -s 10.20.20.13 -s 10.20.20.14
#自動故障VIP切換調用腳本
master_ip_failover_script=/etc/masterha/scripts/master_ip_failover
#手動故障切換調用腳本
master_ip_online_change_script=/etc/masterha/scripts/master_ip_online_change
#發送郵件腳本
report_script=/mha/scripts/send_report
[server1]
hostname=10.20.20.12
candidate_master=1
[server2]
hostname=10.20.20.13
candidate_master=1
[server3]
hostname=10.20.20.14
no_master=1




2、自動故障VIP切換調用腳本


vi /etc/masterha/scripts/master_ip_failover    （在MHA_manager 節點上）


#!/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 = '192.168.1.100';   #Virtual IP
my $gateway = '192.168.1.1';    #Gateway IP
my $interface = 'eth0';          #bind to interface
my $key = "1";
my $ssh_stop_vip = "/sbin/ifconfig $interface:$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 "\n\nIN SCRIPT TEST====$ssh_stop_vip==$ssh_start_vip===\n\n";
  if ( $command eq "stop" || $command eq "stopssh" ) {
    # $orig_master_host, $orig_master_ip, $orig_master_port are passed.
    # If you manage master ip address at global catalog database,
    # invalidate orig_master_ip here.
    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" ) {
    # all arguments are passed.
    # If you manage master ip address at global catalog database,
    # activate new_master_ip here.
    # You can also grant write access (create user, set read_only=0, etc) here.
    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;
  }
  elsif ( $command eq "status" ) {
    print "Checking the Status of the script.. OK \n";
    `ssh $ssh_user\@$orig_master_host \" $ssh_start_vip \"`;
    exit 0;
  }
  else {
    &usage();
    exit 1;
  }
}
# A simple system call that enable the VIP on the new master
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";
}


3、手動故障切換調用腳本  （在MHA_manager）


vi /etc/masterha/scripts/master_ip_online_change 


#!/usr/bin/env perl
#  Copyright (C) 2011 DeNA Co.,Ltd.
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#   along with this program; if not, write to the Free Software
#  Foundation, Inc.,
#  51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
## Note: This is a sample script and is not complete. Modify the script based on your environment.
use strict;
use warnings FATAL => 'all';
use Getopt::Long;
use MHA::DBHelper;
use MHA::NodeUtil;
use Time::HiRes qw( sleep gettimeofday tv_interval );
use Data::Dumper;
my $_tstart;
my $_running_interval = 0.1;
my (
  $command,          $orig_master_host, $orig_master_ip,
  $orig_master_port, $orig_master_user, $orig_master_ssh_user,
  $new_master_host,  $new_master_ip,    $new_master_port,
  $new_master_user,  $new_master_ssh_user, $orig_master_is_new_slave,
  $orig_master_password, $new_master_password,
);
my $vip = '192.168.1.100';      ###Virtual IP
my $gateway = '192.168.1.1';    ###Gateway IP
my $interface = 'eth0';         ###interface
my $key = "1";
my $ssh_start_vip = "/sbin/ifconfig $interface:$key $vip/24";
my $flush_arp = "/sbin/arping -I $interface -c 2 -s $vip $gateway";
my $ssh_stop_vip = "/sbin/ifconfig $interface:$key down";
my $ssh_user = "root";
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,
  'orig_master_user=s'     => \$orig_master_user,
  'orig_master_password=s' => \$orig_master_password,
  'new_master_host=s'      => \$new_master_host,
  'new_master_ip=s'        => \$new_master_ip,
  'new_master_port=i'      => \$new_master_port,
  'new_master_user=s'      => \$new_master_user,
  'new_master_password=s'  => \$new_master_password,
  'orig_master_ssh_user=s'   => \$orig_master_ssh_user,
  'new_master_ssh_user=s'    => \$new_master_ssh_user,
  'orig_master_is_new_slave' => \$orig_master_is_new_slave,
);
exit &main();
sub current_time_us {
  my ( $sec, $microsec ) = gettimeofday();
  my $curdate = localtime($sec);
  return $curdate . " " . sprintf( "%06d", $microsec );
}
sub sleep_until {
  my $elapsed = tv_interval($_tstart);
  if ( $_running_interval > $elapsed ) {
    sleep( $_running_interval - $elapsed );
  }
}
sub get_threads_util {
  my $dbh                    = shift;
  my $my_connection_id       = shift;
  my $running_time_threshold = shift;
  my $type                   = shift;
  $running_time_threshold = 0 unless ($running_time_threshold);
  $type                   = 0 unless ($type);
  my @threads;
  my $sth = $dbh->prepare("SHOW PROCESSLIST");
  $sth->execute();
  while ( my $ref = $sth->fetchrow_hashref() ) {
    my $id         = $ref->{Id};
    my $user       = $ref->{User};
    my $host       = $ref->{Host};
    my $command    = $ref->{Command};
    my $state      = $ref->{State};
    my $query_time = $ref->{Time};
    my $info       = $ref->{Info};
    $info =~ s/^\s*(.*?)\s*$/$1/ if defined($info);
    next if ( $my_connection_id == $id );
    next if ( defined($query_time) && $query_time < $running_time_threshold );
    next if ( defined($command)    && $command eq "Binlog Dump" );
    next if ( defined($user)       && $user eq "system user" );
    next
      if ( defined($command)
      && $command eq "Sleep"
      && defined($query_time)
      && $query_time >= 1 );
    if ( $type >= 1 ) {
      next if ( defined($command) && $command eq "Sleep" );
      next if ( defined($command) && $command eq "Connect" );
    }
    if ( $type >= 2 ) {
      next if ( defined($info) && $info =~ m/^select/i );
      next if ( defined($info) && $info =~ m/^show/i );
    }
    push @threads, $ref;
  }
  return @threads;
}
sub main {
  if ( $command eq "stop" ) {
    ## Gracefully killing connections on the current master
    # 1. Set read_only= 1 on the new master
    # 2. DROP USER so that no app user can establish new connections
    # 3. Set read_only= 1 on the current master
    # 4. Kill current queries
    # * Any database access failure will result in script die.
    my $exit_code = 1;
    eval {
      ## Setting read_only=1 on the new master (to avoid accident)
      my $new_master_handler = new MHA::DBHelper();
      # args: hostname, port, user, password, raise_error(die_on_error)_or_not
      $new_master_handler->connect( $new_master_ip, $new_master_port,
        $new_master_user, $new_master_password, 1 );
      print current_time_us() . " Set read_only on the new master.. ";
      $new_master_handler->enable_read_only();
      if ( $new_master_handler->is_read_only() ) {
        print "ok.\n";
      }
      else {
        die "Failed!\n";
      }
      $new_master_handler->disconnect();
      # Connecting to the orig master, die if any database error happens
      my $orig_master_handler = new MHA::DBHelper();
      $orig_master_handler->connect( $orig_master_ip, $orig_master_port,
        $orig_master_user, $orig_master_password, 1 );
      ## Drop application user so that nobody can connect. Disabling per-session binlog beforehand
      #$orig_master_handler->disable_log_bin_local();
      #print current_time_us() . " Drpping app user on the orig master..\n";
      #FIXME_xxx_drop_app_user($orig_master_handler);
      ## Waiting for N * 100 milliseconds so that current connections can exit
      my $time_until_read_only = 15;
      $_tstart = [gettimeofday];
      my @threads = get_threads_util( $orig_master_handler->{dbh},
        $orig_master_handler->{connection_id} );
      while ( $time_until_read_only > 0 && $#threads >= 0 ) {
        if ( $time_until_read_only % 5 == 0 ) {
          printf
"%s Waiting all running %d threads are disconnected.. (max %d milliseconds)\n",
            current_time_us(), $#threads + 1, $time_until_read_only * 100;
          if ( $#threads < 5 ) {
            print Data::Dumper->new( [$_] )->Indent(0)->Terse(1)->Dump . "\n"
              foreach (@threads);
          }
        }
        sleep_until();
        $_tstart = [gettimeofday];
        $time_until_read_only--;
        @threads = get_threads_util( $orig_master_handler->{dbh},
          $orig_master_handler->{connection_id} );
      }
      ## Setting read_only=1 on the current master so that nobody(except SUPER) can write
      print current_time_us() . " Set read_only=1 on the orig master.. ";
      $orig_master_handler->enable_read_only();
      if ( $orig_master_handler->is_read_only() ) {
        print "ok.\n";
      }
      else {
        die "Failed!\n";
      }
      ## Waiting for M * 100 milliseconds so that current update queries can complete
      my $time_until_kill_threads = 5;
      @threads = get_threads_util( $orig_master_handler->{dbh},
        $orig_master_handler->{connection_id} );
      while ( $time_until_kill_threads > 0 && $#threads >= 0 ) {
        if ( $time_until_kill_threads % 5 == 0 ) {
          printf
"%s Waiting all running %d queries are disconnected.. (max %d milliseconds)\n",
            current_time_us(), $#threads + 1, $time_until_kill_threads * 100;
          if ( $#threads < 5 ) {
            print Data::Dumper->new( [$_] )->Indent(0)->Terse(1)->Dump . "\n"
              foreach (@threads);
          }
        }
        sleep_until();
        $_tstart = [gettimeofday];
        $time_until_kill_threads--;
        @threads = get_threads_util( $orig_master_handler->{dbh},
          $orig_master_handler->{connection_id} );
                &stop_vip();
      ## Terminating all threads
      print current_time_us() . " Killing all application threads..\n";
      $orig_master_handler->kill_threads(@threads) if ( $#threads >= 0 );
      print current_time_us() . " done.\n";
      #$orig_master_handler->enable_log_bin_local();
      $orig_master_handler->disconnect();
      ## After finishing the script, MHA executes FLUSH TABLES WITH READ LOCK
      $exit_code = 0;
    };
    if ($@) {
      warn "Got Error: $@\n";
      exit $exit_code;
    }
    exit $exit_code;
  }
  elsif ( $command eq "start" ) {
    ## Activating master ip on the new master
    # 1. Create app user with write privileges
    # 2. Moving backup script if needed
    # 3. Register new master's ip to the catalog database
# If exit code is 0 or 10, MHA does not abort
    my $exit_code = 10;
    eval {
      my $new_master_handler = new MHA::DBHelper();
      # args: hostname, port, user, password, raise_error_or_not
      $new_master_handler->connect( $new_master_ip, $new_master_port,
        $new_master_user, $new_master_password, 1 );
      ## Set read_only=0 on the new master
      #$new_master_handler->disable_log_bin_local();
      print current_time_us() . " Set read_only=0 on the new master.\n";
      $new_master_handler->disable_read_only();
      ## Creating an app user on the new master
      #print current_time_us() . " Creating app user on the new master..\n";
      #FIXME_xxx_create_app_user($new_master_handler);
      #$new_master_handler->enable_log_bin_local();
      $new_master_handler->disconnect();
      ## Update master ip on the catalog database, etc
                print "Enabling the VIP - $vip on the new master - $new_master_host \n";
                &start_vip();
                &flush_arp();
                $exit_code = 0;
    };
    if ($@) {
      warn "Got Error: $@\n";
      exit $exit_code;
    }
    exit $exit_code;
  }
    exit 0;
  }
  else {
    &usage();
    exit 1;
  }
}
# A simple system call that enable the VIP on the new master
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 \"`;
}
#flush arp
sub flush_arp() {
    `ssh $ssh_user\@$new_master_host \" $flush_arp \"`;
}
sub usage {
  print
"Usage: master_ip_online_change --command=start|stop|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";
  die;
}




4、自動發郵件腳本（自動切換后會觸發郵件， 在MHA_manager）


vi /etc/masterha/scripts/send_report 
#!/usr/bin/perl


#  Copyright (C) 2011 DeNA Co.,Ltd.
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#   along with this program; if not, write to the Free Software
#  Foundation, Inc.,
#  51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA


## Note: This is a sample script and is not complete. Modify the script based on your environment.


use strict;
use warnings FATAL => 'all';
use Mail::Sender;
use Getopt::Long;


#new_master_host and new_slave_hosts are set only when recovering master succeeded
my ( $dead_master_host, $new_master_host, $new_slave_hosts, $subject, $body );


my $smtp='smtp.chinadaas.com';
my $mail_from='support@chinadaas.com';
my $mail_user='support@chinadaas.com';
my $mail_pass='ZS_123456';
#my $mail_to=['chenzhibin@chinadaas.com'];
my $mail_to='chenzhibin@chinadaas.com';


GetOptions(
  'orig_master_host=s' => \$dead_master_host,
  'new_master_host=s'  => \$new_master_host,
  'new_slave_hosts=s'  => \$new_slave_hosts,
  'subject=s'          => \$subject,
  'body=s'             => \$body,
);


# Do whatever you want here
mailToContacts($smtp,$mail_from,$mail_user,$mail_pass,$mail_to,$subject,$body);


sub mailToContacts {
        my ($smtp, $mail_from, $mail_user, $mail_pass, $mail_to, $subject, $msg ) = @_;
        open my $DEBUG, ">/var/log/masterha/app1/mail.log"
                or die "Can't open the debug    file:$!\n";
        my $sender = new Mail::Sender {
                ctype           => 'text/plain;charset=utf-8',
                encoding        => 'utf-8',
                smtp            => $smtp,
                from            => $mail_from,
                auth            => 'LOGIN',
                TLS_allowed     => '0',
                authid          => $mail_user,
                authpwd         => $mail_pass,
                to              => $mail_to,
                subject         => $subject,
                debug           => $DEBUG
        };
        $sender->MailMsg(
                {
                        msg => $msg,
                        debug => $DEBUG
                }
        ) or print $Mail::Sender::Error;
        return 1;
}


exit 0;




5、賦予執行權限
chmod +x /etc/masterha/scripts/master_ip_failover 
chmod +x  /etc/masterha/scripts/master_ip_online_change
chmod +x /etc/masterha/scripts/send_report 


八、檢查狀態
檢查ssh認證狀態（在mha_manager上）
masterha_check_ssh --conf=/etc/masterha/app1.cnf


檢查復制狀態（在mha_manager上）
masterha_check_repl --conf=/etc/masterha/app1.cnf


九、啟動和關閉管理節點


可以通過如下命令啟動mha：
nohup masterha_manager --conf=/etc/masterha/app1.cnf >> /dev/null 2>&1 &


可以通過如下命令停止mha
masterha_stop --conf=/etc/app1.cnf




十、查看管理節點啟動后的服務：
ps -ef |grep master_ip_
ps -ef |grep masterha
或
masterha_check_status -conf=/etc/masterha/app1.cnf 
或
查看管理節點日志信息
tail -f /masterha/app1/manager.log




十一、自動切換測試
在主上建立VIP(只有在故障時，才會觸發腳本，才會生成VIP)：
第一次需要在主庫Mysql_Master：10.101.110.90上手工綁定vip


ifconfig eth0:1 10.101.110.10/24


宕掉主庫（service mysql stop），可以通過日志（tail -f /masterha/app1/manager.log），觀察到自動提升10.20.20.13為主，并將其余的從庫的主庫切為了10.20.20.13
同時，VIP在新主10.20.20.13上自動創建


注意一下事項：
發生主備切換后，manager服務會自動停掉，且在/masterha/app1下面生成
app1.failover.complete，若再次發生切換需要刪除app1.failover.complete文件
rm -fr /masterha/app1/app1.failover.complete


*****如果自動切換后，需要手工執行mha manager啟動腳本，進行監控master 節點，并且刪除 rm -fr /masterha/app1/app1.failover.complete


常情況下自動切換以后，原master可能已經廢棄掉，待原master主機修復后，如果數據完整的情況下，
想把原來master重新作為新主庫的slave，這時我們可以借助當時自動切換時刻的MHA日志來完成對原master的修復
下面是提取相關日志的命令：（在mha_manager上）


原主庫修復，變為備庫需要以下步驟


mha manager節點
[root@mha manager]# grep -i "All other slaves should start" /masterha/app1/manager.log


Mon Apr 21 22:28:33 2014 - [info]  All other slaves should start replication from here. Statement should be: CHANGE MASTER TO MASTER_HOST='10.20.20.13', （新主庫的ip）MASTER_PORT=3306, MASTER_LOG_FILE='mysql-bin.000022', MASTER_LOG_POS=506716, MASTER_USER='repl', MASTER_PASSWORD='xxx';




獲取上述信息以后，就可以直接在修復后的原master上執行change master to相關操作，重新作為從庫了




十二、手工切換


有時候需要手動切換MySQL主服務器，可以使用masterha_master_switch命令，不過它調用的不是master_ip_failover_script腳本，而是master_ip_online_change_script腳本，但調用參數類似，腳本可以互用。


在mha_manager機器上：
masterha_master_switch --master_state=alive --conf=/etc/masterha/app1.cnf --new_master_host=10.20.20.12  --new_master_port=3306 --orig_master_is_new_slave --running_updates_limit=10000 --interactive=0




十三清除relay log （備庫恢復的binlog日志）




對于MHA場景下，對于某些滯后從庫的恢復依賴于其他從庫的relay log，因此采取禁用自動刪除功能以及定期清理的辦法。對于清理過多過大的relay log需要注意引起的復制延遲資源開銷等。MHA可通過purge_relay_logs腳本及配合cronjob來完成此項任務
在幾個MHA node節點上(MHA manager不需要)：
添加如下腳本和任務執行計劃：
[root@JBWDB03 shell]# cat /usr/local/shell/purge_relay_logs.sh     
#!/bin/bash
user=root
passwd='-s4)SVqJ'
port=3306
log_dir='/etc/masterha/log'
work_dir='/etc/masterha/data'
purge='/usr/local/bin/purge_relay_logs'
if [ ! -d $log_dir ]
then
   mkdir $log_dir -p
fi
if [ ! -d $work_dir ]
then
   mkdir $work_dir -p
fi
$purge --user=$user --password=$passwd --disable_relay_log_purge --port=$port --workdir=$work_dir >> $log_dir/purge_relay_logs.log 2>&1
[root@JBWDB03 shell]# crontab -l
##每天凌晨1點清空relay log
00 01 */1 * * /bin/bash /usr/local/shell/purge_relay_logs.sh