MHA+keepalive高可用环境搭建

MHA(Master HighAvailability)目前在MySQL高可用方面是一个相对成熟的解决方案,它由日本DeNA公司youshimaton(现就职于Facebook公司)开发,是一套优秀的作为MySQL高可用性环境下故障切换和主从提升的高可用软件。在MySQL故障切换过程中,MHA能做到在0~30秒之内自动完成数据库的故障切换操作,并且在进行故障切换的过程中,MHA能在最大程度上保证数据的一致性,以达到真正意义上的高可用。

该软件由两部分组成:MHA Manager(管理节点)和MHA Node(数据节点)。

MHA Node运行在每台MySQL服务器上,MHAManager会定时探测集群中的master节点,当master出现故障时,它可以自动将最新数据的slave提升为新的master,然后将所有其他的slave重新指向新的master。整个故障转移过程对应用程序完全透明。

实验环境

10.192.203.201, 10.192.203.101上面安装了keepalive,vip是108

实验步骤

 

1 修改/etc/hosts

在mha管理节点和数据节点所在服务器上添加这些服务器ip和主机名对应关系。

如:

cat /etc/hosts

10.192.203.201 pc2

10.192.203.101 slave1

10.192.203.102 PC

2 Mysql主从复制环境搭建

搭建过程略,可以参考参考:http://blog.csdn.net/yabingshi_tech/article/details/45192599。

要确保两个从库设置read_only。

要确保master和备选master为主主互备模式,否则后面配置过程有可能会发生错误。

 

3 配置主机信任关系 

在所有节点生成密码文件,然后将其拷贝到本机及其他服务器上,这里以10.192.203.201为例:

 # ssh-keygen

# ssh-copy-id  [email protected]

 # ssh-copy-id  [email protected]

 # ssh-copy-id  [email protected]  

然后ssh验证下,是否可以免密码登录。

 

4 安装MHA

点击这里进行下载:

http://download.csdn.net/download/yabignshi/8974251

http://download.csdn.net/detail/yabignshi/8974265 

在所有数据节点上安装:

yum install perl-DBD-MySQL -y

rpm -ivh mha4mysql-node-0.56-0.el6.noarch.rpm

 安装完成后会在/usr/bin目录下生成以下脚本文件(这些工具通常由MHAManager的脚本触发,无需人为操作)

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)

在管理节点上安装:

yum install perl-DBD-MySQL -y(由于本实验环境管理节点和数据节点部署在了同一台服务器上,所以这里不用重复安装)

yum install perl-Config-Tiny -y

yum install epel-release -y

yum install perl-Log-Dispatch -y

yum install perl-Parallel-ForkManager -y

rpm -ivh mha4mysql-node-0.56-0.el6.noarch.rpm(由于本实验环境管理节点和数据节点部署在了同一台服务器上,所以这里不用重复安装)

rpm -ivh mha4mysql-manager-0.56-0.el6.noarch.rpm 

安装完成后会在/usr/bin目录下生成以下脚本文件:

 

-rwxr-xr-x. 1 root      root       1995 Apr  1  2014 masterha_check_repl
-rwxr-xr-x. 1 root      root        1779 Apr 1  2014 masterha_check_ssh
-rwxr-xr-x. 1 root      root       1865 Apr  1  2014 masterha_check_status
-rwxr-xr-x. 1 root      root        3201 Apr 1  2014 masterha_conf_host
-rwxr-xr-x. 1 root      root        2517 Apr 1  2014 masterha_manager
-rwxr-xr-x. 1 root      root        2165 Apr 1  2014 masterha_master_monitor
-rwxr-xr-x. 1 root      root        2373 Apr 1  2014 masterha_master_switch
-rwxr-xr-x. 1 root      root        5171 Apr 1  2014 masterha_secondary_check
-rwxr-xr-x. 1 root      root        1739 Apr 1  2014 masterha_stop
-rwxr-xr-x. 1 root      root       4807 Apr  1  2014 filter_mysqlbinlog
-rwxr-xr-x. 1 root      root       7525 Apr  1  2014 save_binary_logs
-rwxr-xr-x. 1 root      root       8261 Apr  1  2014 purge_relay_logs
-rwxr-xr-x. 1 root      root      16367 Apr  1  2014 apply_diff_relay_logs

 

 

 

5 安装配置keepalive

 

5.1 安装keepalive

在master和备选master上安装keepalive:

 

yum install -y popt-devel
cd /usr/local/src
wget http://www.keepalived.org/software/keepalived-1.2.2.tar.gz
tar zxvf keepalived-1.2.2.tar.gz
cd keepalived-1.2.2
./configure --prefix=/
make
make install

 

 

 

5.2 修改配置文件

vi/etc/keepalived/keepalived.conf

master和备选master配置文件内容相同。

 

#ConfigurationFile for keepalived
global_defs {
notification_email {                        ######定义接受邮件的邮箱
 [email protected]
       }
 notification_email_from [email protected]    ######定义发送邮件的邮箱
 smtp_server mail.tuge.com
 smtp_connect_timeout 10
}
vrrp_instance vrrptest {                 ######定义vrrptest实例
       state BACKUP              ######服务器状态
 interface eth0                     ######使用的接口
       virtual_router_id 51               ######虚拟路由的标志,一组lvs的虚拟路由标识必须相同,这样才能切换
       priority 150                       ######服务启动优先级,值越大,优先级越高,BACKUP 不能大于MASTER
       advert_int 1                        ######服务器之间的存活检查时间
authentication {
       auth_type PASS                     ######认证类型
       auth_pass ufsoft       ######认证密码,一组lvs 服务器的认证密码必须一致
}
virtual_ipaddress {                         ######虚拟IP地址
        10.192.203.108
}
}

 

这里master服务器的state不配置成MASTER,且配置的优先级一样,是期望在master宕机后再恢复时,不主动将MASTER状态抢过来,避免MySQL服务的波动。

这里没有配置vrrp_script,在后面会让mha实现vip的自动漂移。

5.3  vi /etc/sysconfig/iptables

#注意,在两台机器上都要修改。

添加:

-A INPUT-d 10.192.203.108/32 -j ACCEPT

-A INPUT-d 224.0.0.18 -j ACCEPT #添加VRRP通讯支持

注意:第一行中的10.192.203.108需要改成你自己的vip

serviceiptables restart

5.4 启动keepalive

service keepalived start

分别执行ip addr命令,可以在其中一台机器上看到虚拟IP

5.5 测试

停止master服务器keepalived,检查VIP是否切换到备选master服务器(用ip addr命令验证即可);

6 配置Mha

 

6.1 添加管理账号

#在数据节点上执行以下操作

grant all privileges on *.* TO mha@'10.192.%' IDENTIFIED BY 'test'; 

flush privileges;

6.2 配置/etc/mha/app1.cnf

 #只在管理端做

 mkdir /etc/mha

 mkdir -p /var/log/mha/app1 

vi /etc/mha/app1.cnf

添加:

 

[server default]
manager_log=/var/log/mha/app1/manager.log
manager_workdir=/var/log/mha/app1.log
master_binlog_dir=/data/mysql/data
master_ip_failover_script= /usr/bin/master_ip_failover     
master_ip_online_change_script=/usr/bin/master_ip_online_change
report_script=/usr/bin/send_report 
user=mha
password=test
ping_interval=2
repl_password=beijing
repl_user=rep_user
ssh_user=root
 
[server1]
hostname=10.192.203.201
port=3306
 
[server2]
candidate_master=1
check_repl_delay=0
hostname=10.192.203.101
port=3306
 
[server3]
hostname=10.192.203.102
port=3306

 

在server default中的配置,是三台数据节点共同的配置,也可以放到具体的server中进行定制。
/*
参数概念解释:

master_binlog_dir=/data/mysql/data #设置master 保存binlog的位置,以便MHA可以找到master的日志

master_ip_failover_script=/usr/bin/master_ip_failover         #设置自动failover时候的切换脚本

master_ip_online_change_script=/usr/bin/master_ip_online_change  #设置手动切换时候的切换脚本

report_script=/usr/bin/send_report                            //设置发生切换后发送的报警的脚本

ping_interval=2 #设置监控主库,发送ping包的时间间隔,默认是3秒,尝试三次没有回应的时候自动进行failover

candidate_master=1 #设置为候选master,如果设置该参数以后,发生主从切换以后将会将此从库提升为主库,即使这个主库不是集群中事件最新的slave

check_repl_delay=0 #默认情况下如果一个slave落后master 100M的relay logs的话,MHA将不会选择该slave作为一个新的master,因为对于这个slave的恢复需要花费很长时间,通过设置check_repl_delay=0,MHA触发切换在选择一个新的master的时候将会忽略复制延时,这个参数对于设置了candidate_master=1的主机非常有用,因为这个候选主在切换的过程中一定是新的master

*/ 

6.3 master_ip_failover脚本代码

要想把keepalived服务引入MHA,我们只需要修改切换是触发的脚本文件master_ip_failover即可,在该脚本中添加在master发生宕机时对keepalived的处理。

在管理节点编辑脚本/usr/bin/master_ip_failover,修改后如下:

 

#!/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 = '10.192.203.108';
my $ssh_start_vip ="/etc/init.d/keepalived start";
my $ssh_stop_vip ="/etc/init.d/keepalived stop";
 
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 SCRIPTTEST====$ssh_stop_vip==$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 VIPon 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";
}


注意:my $vip = '10.192.203.108';这一行中的vip请根据情况改成自己的虚拟IP。

 

chmod +x /usr/bin/master_ip_failover

6.4 master_ip_online_change脚本代码

在管理节点编辑脚本/usr/bin/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
#  itunder 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.,
#  51Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 
## Note: This is a sample script and is notcomplete. 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 gettimeofdaytv_interval );
use Data::Dumper;
 
my $_tstart;
my $_running_interval = 0.1;
my (
 $command,             $orig_master_is_new_slave, $orig_master_host,
 $orig_master_ip,      $orig_master_port,        $orig_master_user,
 $orig_master_password, $orig_master_ssh_user,     $new_master_host,
 $new_master_ip,       $new_master_port,         $new_master_user,
 $new_master_password, $new_master_ssh_user
);
my $vip = '10.192.203.108/32';
my $key = '1';
my $ssh_start_vip = "/etc/init.d/keepalivedstart";
my $ssh_stop_vip = "/etc/init.d/keepalivedstop";
my $orig_master_ssh_port = 22;
my $new_master_ssh_port = 22;
GetOptions(
 'command=s'                =>\$command,
 'orig_master_is_new_slave' => \$orig_master_is_new_slave,
 '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,
 'orig_master_ssh_user=s'   =>\$orig_master_ssh_user,
 '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,
 'new_master_ssh_user=s'    =>\$new_master_ssh_user,
 'orig_master_ssh_port=i'    =>\$orig_master_ssh_port,
 'new_master_ssh_port=i'    =>\$new_master_ssh_port,
);
 
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. Disablingper-session binlog beforehand
     $orig_master_handler->disable_log_bin_local();
      print current_time_us() . " Drpping appuser on the orig master..\n";
     #FIXME_xxx_drop_app_user($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 aredisconnected.. (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(exceptSUPER) 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 cancomplete
     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 aredisconnected.. (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} );
     }
 
     ## Terminating all threads
     print current_time_us() . " Killing all applicationthreads..\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
     eval {
     `ssh -p$orig_master_ssh_port $orig_master_ssh_user\@$orig_master_host\" $ssh_stop_vip \"`;
       };
       if ($@) {
           warn $@;
       }
     $exit_code = 0;
   };
   if ($@) {
     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
 
# We don't return error even thoughactivating updatable accounts/ip failed so that we don't interrupt slaves'recovery.
# If exit code is 0 or 10, MHA does notabort
   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() . " Setread_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 newmaster..\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
     `ssh -p$new_master_ssh_port $new_master_ssh_user\@$new_master_host\" $ssh_start_vip \"`;
     $exit_code = 0;
   };
   if ($@) {
     warn "Got Error: $@\n";
     exit $exit_code;
    }
   exit $exit_code;
  }
 elsif ( $command eq "status" ) {
 
    #do nothing
   exit 0;
  }
 else {
   &usage();
   exit 1;
  }
}
 
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;
}

 

注意:需要把my $vip = '10.192.203.108/32';改成自己的vip即可。

chmod +x /usr/bin/master_ip_online_change

6.5 send_report脚本代码

在管理节点编辑脚本/usr/bin/send_report

 

#!/usr/bin/perl
 
# Copyright (C) 2011 DeNA Co.,Ltd.
#
# This program is free software; you can redistribute it and/or modify
#  itunder 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.,
#  51Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 
## Note: This is a sample script and is notcomplete. 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 areset only when recovering master succeeded
my ( $dead_master_host, $new_master_host, $new_slave_hosts,$subject, $body );
my $smtp='smtp.163.com';
my $mail_from='[email protected]';
my $mail_user='[email protected]';
my $mail_pass='Password';
my$mail_to=['[email protected]','[email protected]'];
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,
);
 
mailToContacts($smtp,$mail_from,$mail_user,$mail_pass,$mail_to,$subject,$body);
 
sub mailToContacts {
   my ( $smtp, $mail_from, $user, $passwd, $mail_to, $subject, $msg ) = @_;
   open my $DEBUG, "> /tmp/monitormail.log"
       or die "Can't open the debug     file:$!\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      => $user,
       authpwd     => $passwd,
       to          => $mail_to,
       subject     => $subject,
       debug       => $DEBUG
   };
 
   $sender->MailMsg(
       {   msg   => $msg,
           debug => $DEBUG
       }
    )or print $Mail::Sender::Error;
   return 1;
}
 
 
 
# Do whatever you want here
 
exit 0;
 
注意:需要修改下以下几行内容:
my $smtp='smtp.163.com';
my $mail_from='[email protected]';
my $mail_user='[email protected]';
my $mail_pass='Password';
my$mail_to=['[email protected]','[email protected]'];

 

#f赋予执行权限

chmod +x /usr/bin/send_report 

注意:需要确保管理节点服务器可以正常发送邮件。可以先用sendEmail命令试下。

6.6 设置relay log的清除方式(在每个slave节点上)

从服务器配置文件要确保relay_log_purge=0,否则在masterha_check_repl时会报错warning,relay_log_purge=0 is not set on slave

主库将来发生切换变成一个从库后,记得在原先的主库上也执行该操作。

MHA在发生切换的过程中,从库的恢复过程中依赖于relay log的相关信息,所以这里要将relay log的自动清除设置为OFF,采用手动清除relay log的方式。

在默认情况下,从服务器上的中继日志会在SQL线程执行完毕后被自动删除。

但是在MHA环境中,这些中继日志在恢复其他从服务器时可能会被用到,因此需要禁用中继日志的自动删除功能。

定期清除中继日志需要考虑到复制延时的问题。在ext3的文件系统下,删除大的文件需要一定的时间,会导致严重的复制延时。

为了避免复制延时,需要暂时为中继日志创建硬链接,因为在linux系统中通过硬链接删除大文件速度会很快。

(在mysql数据库中,删除大表时,通常也采用建立硬链接的方式)

 

7 检查mha manage是不是配置成功 

7.1 检查ssh登录 

 

 [[email protected]]#  masterha_check_ssh--conf=/etc/mha/app1.cnf
Mon Feb 13 15:35:25 2017 - [warning] Globalconfiguration file /etc/masterha_default.cnf not found. Skipping.
Mon Feb 13 15:35:25 2017 - [info] Readingapplication default configuration from /etc/mha/app1.cnf..
Mon Feb 13 15:35:25 2017 - [info] Readingserver configuration from /etc/mha/app1.cnf..
Mon Feb 13 15:35:25 2017 - [info] StartingSSH connection tests..
Mon Feb 13 15:35:26 2017 - [debug]
Mon Feb 13 15:35:25 2017 - [debug]  Connecting via SSH [email protected](10.192.203.201:22) [email protected](10.192.203.101:22)..
Mon Feb 13 15:35:25 2017 - [debug]   ok.
Mon Feb 13 15:35:25 2017 - [debug]  Connecting via SSH [email protected](10.192.203.201:22) [email protected](10.192.203.102:22)..
Mon Feb 13 15:35:26 2017 - [debug]   ok.
Mon Feb 13 15:35:26 2017 - [debug]
Mon Feb 13 15:35:25 2017 - [debug]  Connecting via SSH [email protected](10.192.203.101:22) [email protected](10.192.203.201:22)..
Mon Feb 13 15:35:25 2017 - [debug]   ok.
Mon Feb 13 15:35:25 2017 - [debug]  Connecting via SSH [email protected](10.192.203.101:22) [email protected](10.192.203.102:22)..
Mon Feb 13 15:35:26 2017 - [debug]   ok.
Mon Feb 13 15:35:27 2017 - [debug]
Mon Feb 13 15:35:26 2017 - [debug]  Connecting via SSH [email protected](10.192.203.102:22) [email protected](10.192.203.201:22)..
Mon Feb 13 15:35:26 2017 - [debug]   ok.
Mon Feb 13 15:35:26 2017 - [debug]  Connecting via SSH [email protected](10.192.203.102:22) [email protected](10.192.203.101:22)..
Mon Feb 13 15:35:27 2017 - [debug]   ok.
Mon Feb 13 15:35:27 2017 - [info] All SSHconnection tests passed successfully.

 

假如ssh可以免密码登录其他几台服务器,但检查ssh时却报错:

 

 [root@PC .ssh]#  masterha_check_ssh--conf=/etc/mha/app1.cnf 
Fri Feb 10 10:04:35 2017 - [warning] Globalconfiguration file /etc/masterha_default.cnf not found. Skipping.
Fri Feb 10 10:04:35 2017 - [info] Readingapplication default configuration from /etc/mha/app1.cnf..
Fri Feb 10 10:04:35 2017 - [info] Readingserver configuration from /etc/mha/app1.cnf..
Fri Feb 10 10:04:35 2017 - [info] StartingSSH connection tests..
Fri Feb 10 10:04:36 2017 -[error][/usr/share/perl5/vendor_perl/MHA/SSHCheck.pm, ln63]
Fri Feb 10 10:04:35 2017 - [debug]  Connecting via SSH [email protected](10.192.203.201:22) [email protected](10.192.203.101:22)..
Warning: Permanently added '10.192.203.201'(RSA) to the list of known hosts.
Permission denied(publickey,gssapi-keyex,gssapi-with-mic,password).
Fri Feb 10 10:04:35 2017 -[error][/usr/share/perl5/vendor_perl/MHA/SSHCheck.pm, ln111] SSH connectionfrom [email protected](10.192.203.201:22) [email protected](10.192.203.101:22) failed!
Fri Feb 10 10:04:37 2017 - [debug]
Fri Feb 10 10:04:36 2017 - [debug]  Connecting via SSH [email protected](10.192.203.101:22) [email protected](10.192.203.201:22)..
Fri Feb 10 10:04:36 2017 - [debug]   ok.
Fri Feb 10 10:04:36 2017 - [debug]  Connecting via SSH [email protected](10.192.203.101:22) [email protected](10.192.203.102:22)..
Fri Feb 10 10:04:37 2017 - [debug]   ok.
Fri Feb 10 10:04:38 2017 - [debug]
Fri Feb 10 10:04:36 2017 - [debug]  Connecting via SSH [email protected](10.192.203.102:22) [email protected](10.192.203.201:22)..
Fri Feb 10 10:04:37 2017 - [debug]   ok.
Fri Feb 10 10:04:37 2017 - [debug]  Connecting via SSH [email protected](10.192.203.102:22) to [email protected](10.192.203.101:22)..
Fri Feb 10 10:04:38 2017 - [debug]   ok.
SSH Configuration Check Failed!
 at/usr/bin/masterha_check_ssh line 44

 

 需要检查下:

①   /etc/hosts文件是否配置正确;

② 密码文件是否ssh-copy-id到了自身服务器。

假如遇到这个错误,修正后,将.ssh下的内容全部清空,然后重新认证即可。

 

7.2 检查mysql replication是否配置成功

[root@pc2 app1]# masterha_check_repl--conf=/etc/mha/app1.cnf

 

Fri Feb 10 11:25:05 2017 - [warning] Globalconfiguration file /etc/masterha_default.cnf not found. Skipping.
Fri Feb 10 11:25:05 2017 - [info] Readingapplication default configuration from /etc/mha/app1.cnf..
Fri Feb 10 11:25:05 2017 - [info] Readingserver configuration from /etc/mha/app1.cnf..
Fri Feb 10 11:25:05 2017 - [info]MHA::MasterMonitor version 0.56.
Fri Feb 10 11:25:06 2017 -[error][/usr/share/perl5/vendor_perl/MHA/ServerManager.pm, ln193] There is noalive slave. We can't do failover
Fri Feb 10 11:25:06 2017 -[error][/usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm, ln424] Errorhappened on checking configurations.  at/usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm line 326
Fri Feb 10 11:25:06 2017 -[error][/usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm, ln523] Errorhappened on monitoring servers.
Fri Feb 10 11:25:06 2017 - [info] Got exitcode 1 (Not master dead).
 
MySQL Replication Health is NOT OK!

 

明明我检查了复制状态都是正常的,为什么通不过呢?

解决办法:

需要确保master和备选master设置为双主复制。即让master也指向备选master。

 

再次验证,假如报错:

[root@pc2 mysql]#  masterha_check_repl --conf=/etc/mha/app1.cnf

 

Mon Feb 13 17:21:52 2017 - [info]   Connecting [email protected](10.192.203.101:22)..
 Checking slave recovery environment settings..
   Opening /data/mysql/relay-log.info ... ok.
   Relay log found at /data/mysql, up to slave1-relay-bin.000011
   Temporary relay log file is /data/mysql/slave1-relay-bin.000011
   Testing mysql connection and privileges..ERROR 1045 (28000): Accessdenied for user 'mha'@'slave1' (using password: YES)
mysql command failed with rc 1:0!
 at/usr/bin/apply_diff_relay_logs line 375
         main::check()called at /usr/bin/apply_diff_relay_logs line 497
         eval{...} called at /usr/bin/apply_diff_relay_logs line 475
         main::main()called at /usr/bin/apply_diff_relay_logs line 120
Mon Feb 13 17:21:53 2017 -[error][/usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm, ln205] Slavessettings check failed!
Mon Feb 13 17:21:53 2017 - [error][/usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm,ln413] Slave configuration failed.
Mon Feb 13 17:21:53 2017 -[error][/usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm, ln424] Errorhappened on checking configurations.  at/usr/bin/masterha_check_repl line 48
Mon Feb 13 17:21:53 2017 -[error][/usr/share/perl5/vendor_perl/MHA/MasterMonitor.pm, ln523] Errorhappened on monitoring servers.
Mon Feb 13 17:21:53 2017 - [info] Got exitcode 1 (Not master dead).
 
MySQL Replication Health is NOT OK!

 

解决办法:

在slave1上创建用户:

mysql> grant  ALL PRIVILEGES ON *.* TO 'mha'@'slave1'identified by 'test';

Query OK, 0 rows affected (0.00 sec) 

mysql> flush privileges;

Query OK, 0 rows affected (0.00 sec)

同理,在PC上创建用户:

mysql> grant  ALL PRIVILEGES ON *.* TO 'mha'@'PC' identifiedby 'test';

Query OK, 0 rows affected (0.00 sec) 

mysql> flush privileges;

Query OK, 0 rows affected (0.00 sec)

  

再次验证时,假如报错:

Can't exec "mysqlbinlog": No suchfile or directory at /usr/share/perl5/vendor_perl/MHA/BinlogManager.pm line106.

mysqlbinlog version command failed with rc1:0, please verify PATH, LD_LIBRARY_PATH, and client options

解决办法:

在所有数据节点上都创建一下软连接:

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

再次验证,报错:

Testing mysql connection andprivileges..sh: mysql: command not found

mysql command failed with rc 127:0!

解决办法:

在所有数据节点上建立软连接:

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

最后,一切正常:

[root@pc2 mysql]#  masterha_check_repl --conf=/etc/mha/app1.cnf

 

Mon Feb 13 17:32:49 2017 - [warning] Globalconfiguration file /etc/masterha_default.cnf not found. Skipping.
Mon Feb 13 17:32:49 2017 - [info] Readingapplication default configuration from /etc/mha/app1.cnf..
Mon Feb 13 17:32:49 2017 - [info] Readingserver configuration from /etc/mha/app1.cnf..
Mon Feb 13 17:32:49 2017 - [info]MHA::MasterMonitor version 0.56.
Mon Feb 13 17:32:49 2017 - [info]Multi-master configuration is detected. Current primary(writable) master is10.192.203.201(10.192.203.201:3306)
Mon Feb 13 17:32:49 2017 - [info] Masterconfigurations are as below:
Master 10.192.203.101(10.192.203.101:3306),replicating from 10.192.203.201(10.192.203.201:3306), read-only
Master 10.192.203.201(10.192.203.201:3306),replicating from 10.192.203.101(10.192.203.101:3306)
 
Mon Feb 13 17:32:49 2017 - [info] GTID failovermode = 0
Mon Feb 13 17:32:49 2017 - [info] DeadServers:
Mon Feb 13 17:32:49 2017 - [info] AliveServers:
Mon Feb 13 17:32:49 2017 - [info]   10.192.203.201(10.192.203.201:3306)
Mon Feb 13 17:32:49 2017 - [info]   10.192.203.101(10.192.203.101:3306)
Mon Feb 13 17:32:49 2017 - [info]   10.192.203.102(10.192.203.102:3306)
Mon Feb 13 17:32:49 2017 - [info] AliveSlaves:
Mon Feb 13 17:32:49 2017 - [info]   10.192.203.101(10.192.203.101:3306)  Version=5.5.19-log (oldest major versionbetween slaves) log-bin:enabled
Mon Feb 13 17:32:49 2017 - [info]     Replicating from10.192.203.201(10.192.203.201:3306)
Mon Feb 13 17:32:49 2017 - [info]     Primary candidate for the new Master(candidate_master is set)
Mon Feb 13 17:32:49 2017 - [info]   10.192.203.102(10.192.203.102:3306)  Version=5.5.19-log (oldest major versionbetween slaves) log-bin:enabled
Mon Feb 13 17:32:49 2017 - [info]     Replicating from10.192.203.201(10.192.203.201:3306)
Mon Feb 13 17:32:49 2017 - [info] CurrentAlive Master: 10.192.203.201(10.192.203.201:3306)
Mon Feb 13 17:32:49 2017 - [info] Checkingslave configurations..
Mon Feb 13 17:32:49 2017 - [info] Checkingreplication filtering settings..
Mon Feb 13 17:32:49 2017 - [info]  binlog_do_db= , binlog_ignore_db=
Mon Feb 13 17:32:49 2017 - [info]  Replication filtering check ok.
Mon Feb 13 17:32:49 2017 - [info] GTID(with auto-pos) is not supported
Mon Feb 13 17:32:49 2017 - [info] StartingSSH connection tests..
Mon Feb 13 17:32:51 2017 - [info] All SSHconnection tests passed successfully.
Mon Feb 13 17:32:51 2017 - [info] CheckingMHA Node version..
Mon Feb 13 17:32:52 2017 - [info]  Version check ok.
Mon Feb 13 17:32:52 2017 - [info] CheckingSSH publickey authentication settings on the current master..
Mon Feb 13 17:32:52 2017 - [info]HealthCheck: SSH to 10.192.203.201 is reachable.
Mon Feb 13 17:32:52 2017 - [info] MasterMHA Node version is 0.56.
Mon Feb 13 17:32:52 2017 - [info] Checkingrecovery script configurations on 10.192.203.201(10.192.203.201:3306)..
Mon Feb 13 17:32:52 2017 - [info]   Executing command: save_binary_logs--command=test --start_pos=4 --binlog_dir=/data/mysql--output_file=/var/tmp/save_binary_logs_test --manager_version=0.56--start_file=single-mysql-bin.000018
Mon Feb 13 17:32:52 2017 - [info]   Connecting [email protected](10.192.203.201:22)..
 Creating /var/tmp if not exists..   ok.
 Checking output directory is accessible or not..
  ok.
 Binlog found at /data/mysql, up to single-mysql-bin.000018
Mon Feb 13 17:32:52 2017 - [info] Binlogsetting check done.
Mon Feb 13 17:32:52 2017 - [info] CheckingSSH publickey authentication and checking recovery script configurations on allalive slave servers..
Mon Feb 13 17:32:52 2017 - [info]   Executing command : apply_diff_relay_logs--command=test --slave_user='mha' --slave_host=10.192.203.101--slave_ip=10.192.203.101 --slave_port=3306 --workdir=/var/tmp--target_version=5.5.19-log --manager_version=0.56--relay_log_info=/data/mysql/relay-log.info --relay_dir=/data/mysql/ --slave_pass=xxx
Mon Feb 13 17:32:52 2017 - [info]   Connecting [email protected](10.192.203.101:22)..
 Checking slave recovery environment settings..
   Opening /data/mysql/relay-log.info ... ok.
   Relay log found at /data/mysql, up to slave1-relay-bin.000011
    Temporaryrelay log file is /data/mysql/slave1-relay-bin.000011
   Testing mysql connection and privileges.. done.
   Testing mysqlbinlog output.. done.
   Cleaning up test file(s).. done.
Mon Feb 13 17:32:52 2017 - [info]   Executing command : apply_diff_relay_logs--command=test --slave_user='mha' --slave_host=10.192.203.102--slave_ip=10.192.203.102 --slave_port=3306 --workdir=/var/tmp--target_version=5.5.19-log --manager_version=0.56--relay_log_info=/data/mysql/relay-log.info --relay_dir=/data/mysql/ --slave_pass=xxx
Mon Feb 13 17:32:52 2017 - [info]   Connecting [email protected](10.192.203.102:22)..
 Checking slave recovery environment settings..
   Opening /data/mysql/relay-log.info ... ok.
   Relay log found at /data/mysql, up to PC-relay-bin.000011
   Temporary relay log file is /data/mysql/PC-relay-bin.000011
   Testing mysql connection and privileges.. done.
   Testing mysqlbinlog output.. done.
   Cleaning up test file(s).. done.
Mon Feb 13 17:32:53 2017 - [info] Slavessettings check done.
Mon Feb 13 17:32:53 2017 - [info]
10.192.203.201(10.192.203.201:3306)(current master)
 +--10.192.203.101(10.192.203.101:3306)
 +--10.192.203.102(10.192.203.102:3306)
 
Mon Feb 13 17:32:53 2017 - [info] Checkingreplication health on 10.192.203.101..
Mon Feb 13 17:32:53 2017 - [info]  ok.
Mon Feb 13 17:32:53 2017 - [info] Checkingreplication health on 10.192.203.102..
Mon Feb 13 17:32:53 2017 - [info]  ok.
Mon Feb 13 17:32:53 2017 - [info] Checkingmaster_ip_failover_script status:
Mon Feb 13 17:32:53 2017 - [info]   /usr/bin/master_ip_failover --command=status--ssh_user=root --orig_master_host=10.192.203.201--orig_master_ip=10.192.203.201 --orig_master_port=3306
 
 
IN SCRIPT TEST====/etc/init.d/keepalivedstop==/etc/init.d/keepalived start===
 
Checking the Status of the script.. OK
Mon Feb 13 17:32:53 2017 - [info]  OK.
Mon Feb 13 17:32:53 2017 - [warning]shutdown_script is not defined.
Mon Feb 13 17:32:53 2017 - [info] Got exitcode 0 (Not master dead).
 
MySQL Replication Health is OK.
 

 

 

 

8 在管理端启动监控

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 & 

 #查看状态

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

app1 (pid:3349) is running(0:PING_OK),master:10.192.203.201

9 验证故障转移

10.192.203.201上关闭Mysql实例:

 [root@pc2mha]# service mysqld stop

Shutting downMySQL... SUCCESS!

 在管理节点上查看日志:

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

会看到:

 

Started automated(non-interactive)failover.
Invalidated master IP address on10.192.203.201(10.192.203.201:3306)
The latest slave10.192.203.101(10.192.203.101:3306) has all relay logs for recovery.
Selected10.192.203.101(10.192.203.101:3306) as a new master.
10.192.203.101(10.192.203.101:3306): OK:Applying all logs succeeded.
10.192.203.101(10.192.203.101:3306): OK:Activated master IP address.
10.192.203.102(10.192.203.102:3306): Thishost has the latest relay log events.
Generating relay diff files from the latestslave succeeded.
10.192.203.102(10.192.203.102:3306): OK:Applying all logs succeeded. Slave started, replicating from10.192.203.101(10.192.203.101:3306)
10.192.203.101(10.192.203.101:3306):Resetting slave info succeeded.
Master failover to10.192.203.101(10.192.203.101:3306) completed successfully.
Mon Feb 13 17:44:28 2017 - [info] Sendingmail..
Unknown option: conf

 

也收到了报警邮件:

MHA+keepalive高可用环境搭建_第1张图片

Vip也漂移过来了:

 

[root@slave1 mysql]# ip addr
1: lo:  mtu16436 qdisc noqueue state UNKNOWN
    link/loopback 00:00:00:00:00:00 brd00:00:00:00:00:00
   inet 127.0.0.1/8 scope host lo
   inet6 ::1/128 scope host
      valid_lft forever preferred_lft forever
2: eth0: mtu 1500 qdisc pfifo_fast state UP qlen1000
   link/ether 08:00:27:04:05:16 brd ff:ff:ff:ff:ff:ff
   inet 10.192.203.101/24 brd 10.192.203.255 scope global eth0
   inet 10.192.203.108/32 scope global eth0
   inet6 fe80::a00:27ff:fe04:516/64 scope link tentative dadfailed
      valid_lft forever preferred_lft forever
3: eth1: mtu 1500 qdisc pfifo_fast state UP qlen1000
   link/ether 08:00:27:3a:ec:3c brd ff:ff:ff:ff:ff:ff
   inet 10.0.10.5/24 brd 10.0.10.255 scope global eth1
   inet6 fe80::a00:27ff:fe3a:ec3c/64 scope link tentative dadfailed
      valid_lft forever preferred_lft forever

 

在PC上查看下slave状态:

mysql> show slave status \G;

*************************** 1. row***************************

               Slave_IO_State: Waiting formaster to send event

                  Master_Host: 10.192.203.101

                  Master_User: rep_user

                  Master_Port: 3306

可以看到10.192.203.102复制自动指向了10.192.203.101了。 

在现在的master上查看变量read_only,发现被自动关闭了,说明之前的slave现在可写了:

mysql> showvariables like 'read_only';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| read_only     | OFF   |
+---------------+-------+
1 row in set (0.01 sec)
 

切换完成后,manager进程会自动挂掉:

[root@pc2 mysql]#  masterha_check_status --conf=/etc/mha/app1.cnf

app1 is stopped(2:NOT_RUNNING).

mha配置文件被自己修改了(原主库的配置信息被删除掉了)

[root@pc2 mha]# cat app1.cnf

 

[server default]
manager_log=/var/log/mha/app1/manager.log
manager_workdir=/var/log/mha/app1.log
master_binlog_dir=/data/mysql
master_ip_failover_script=/usr/bin/master_ip_failover
master_ip_online_change_script=/usr/bin/master_ip_online_change
password=test
ping_interval=2
repl_password=beijing
repl_user=rep_user
report_script=/usr/bin/send_report
ssh_user=root
user=mha
 
[server2]
candidate_master=1
check_repl_delay=0
hostname=10.192.203.101
port=3306
 
[server3]
hostname=10.192.203.102
port=3306
 

 

现在的主库10.192.203.101上已经没有它原先的主从复制信息:

mysql> showslave status \G;

Empty set (0.00sec)

 

ERROR:

No queryspecified

 

接下来我们该做的事情:

①     找出主库挂到的原因,并修复之

②     确保原先的主库现在已追赶上现在的主库,并继续正确复制

③     在现在的主库上change master to指向原来的主库开始复制,为将来故障切换做好准备。

④     检查当前主从复制状态是否正常(masterha_check_repl--conf=/etc/mha/app1.cnf)

⑤     启动原先主库keepalive进程

⑥     确保原先主库配置文件(read_only设置为1relay_log_purge=0)

⑦     修改mha配置文件,将原先的主库信息重新加入

⑧     启动manager进程,检查mha状态是否正常

10 在线切换

在许多情况下,需要将现有的主服务器迁移到另外一台服务器上。比如主服务器硬件故障,RAID 控制卡需要重建,将主服务器移到性能更好的服务器上等等。维护主服务器引起性能下降,导致停机时间至少无法写入数据。另外, 阻塞或杀掉当前运行的会话会导致主主之间数据不一致的问题发生。 MHA 提供快速切换和优雅的阻

塞写入,这个切换过程只需要 0.5-2s 的时间,这段时间内数据是无法写入的。在很多情况下,0.5-2s 的阻塞写入是可以接受的。因此切换主服务器不需要计划分配维护时间窗口。

MHA在线切换的大概过程:

(1)检测复制设置和确定当前主服务器

(2)确定新的主服务器

(3)阻塞写入到当前主服务器

(4)等待所有从服务器赶上复制

(5)授予写入到新的主服务器

(6)重新设置从服务器

 

假如现在我想从10.192.203.101切换回10.192.203.201,通过在线切换的方式完成。

10.1 停掉MHA监控

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

10.2 在线切换

[root@pc2 bin]# masterha_master_switch--conf=/etc/mha/app1.cnf --master_state=alive --new_master_host=10.192.203.201--new_master_port=3306 --orig_master_is_new_slave --running_updates_limit=10000

 

Tue Feb 14 02:44:20 2017 - [info]MHA::MasterRotate version 0.56.
Tue Feb 14 02:44:20 2017 - [info] Startingonline master switch..
Tue Feb 14 02:44:20 2017 - [info]
Tue Feb 14 02:44:20 2017 - [info] * Phase1: Configuration Check Phase..
Tue Feb 14 02:44:20 2017 - [info]
Tue Feb 14 02:44:20 2017 - [warning] Globalconfiguration file /etc/masterha_default.cnf not found. Skipping.
Tue Feb 14 02:44:20 2017 - [info] Readingapplication default configuration from /etc/mha/app1.cnf..
Tue Feb 14 02:44:20 2017 - [info] Readingserver configuration from /etc/mha/app1.cnf..
Tue Feb 14 02:44:20 2017 - [info]Multi-master configuration is detected. Current primary(writable) master is10.192.203.101(10.192.203.101:3306)
Tue Feb 14 02:44:20 2017 - [info] Masterconfigurations are as below:
Master 10.192.203.101(10.192.203.101:3306),replicating from 10.192.203.201(10.192.203.201:3306)
Master 10.192.203.201(10.192.203.201:3306),replicating from 10.192.203.101(10.192.203.101:3306), read-only
 
Tue Feb 14 02:44:20 2017 - [info] GTIDfailover mode = 0
Tue Feb 14 02:44:20 2017 - [info] CurrentAlive Master: 10.192.203.101(10.192.203.101:3306)
Tue Feb 14 02:44:20 2017 - [info] AliveSlaves:
Tue Feb 14 02:44:20 2017 - [info]   10.192.203.201(10.192.203.201:3306)  Version=5.5.19-log (oldest major versionbetween slaves) log-bin:enabled
Tue Feb 14 02:44:20 2017 - [info]     Replicating from10.192.203.101(10.192.203.101:3306)
Tue Feb 14 02:44:20 2017 - [info]   10.192.203.102(10.192.203.102:3306)  Version=5.5.19-log (oldest major versionbetween slaves) log-bin:enabled
Tue Feb 14 02:44:20 2017 - [info]     Replicating from10.192.203.101(10.192.203.101:3306)
 
It is better to execute FLUSHNO_WRITE_TO_BINLOG TABLES on the master before switching. Is it ok to executeon 10.192.203.101(10.192.203.101:3306)? (YES/no): yes
Tue Feb 14 02:45:03 2017 - [info] ExecutingFLUSH NO_WRITE_TO_BINLOG TABLES. This may take long time..
Tue Feb 14 02:45:03 2017 - [info]  ok.
Tue Feb 14 02:45:03 2017 - [info] CheckingMHA is not monitoring or doing failover..
Tue Feb 14 02:45:03 2017 - [info] Checkingreplication health on 10.192.203.201..
Tue Feb 14 02:45:03 2017 - [info]  ok.
Tue Feb 14 02:45:03 2017 - [info] Checkingreplication health on 10.192.203.102..
Tue Feb 14 02:45:03 2017 - [info]  ok.
Tue Feb 14 02:45:03 2017 - [info]10.192.203.201 can be new master.
Tue Feb 14 02:45:03 2017 - [info]
From:
10.192.203.101(10.192.203.101:3306)(current master)
 +--10.192.203.201(10.192.203.201:3306)
 +--10.192.203.102(10.192.203.102:3306)
 
To:
10.192.203.201(10.192.203.201:3306) (newmaster)
 +--10.192.203.102(10.192.203.102:3306)
 +--10.192.203.101(10.192.203.101:3306)
 
Starting master switch from10.192.203.101(10.192.203.101:3306) to 10.192.203.201(10.192.203.201:3306)?(yes/NO): yes
Tue Feb 14 02:45:09 2017 - [info] Checkingwhether 10.192.203.201(10.192.203.201:3306) is ok for the new master..
Tue Feb 14 02:45:09 2017 - [info]  ok.
Tue Feb 14 02:45:09 2017 - [info] ** Phase1: Configuration Check Phase completed.
Tue Feb 14 02:45:09 2017 - [info]
Tue Feb 14 02:45:09 2017 - [info] * Phase2: Rejecting updates Phase..
Tue Feb 14 02:45:09 2017 - [info]
Tue Feb 14 02:45:09 2017 - [info] Executingmaster ip online change script to disable write on the current master:
Tue Feb 14 02:45:09 2017 - [info]   /usr/bin/master_ip_online_change--command=stop --orig_master_host=10.192.203.101--orig_master_ip=10.192.203.101 --orig_master_port=3306--orig_master_user='mha' --orig_master_password='test'--new_master_host=10.192.203.201 --new_master_ip=10.192.203.201--new_master_port=3306 --new_master_user='mha' --new_master_password='test' --orig_master_ssh_user=root--new_master_ssh_user=root  --orig_master_is_new_slave
Tue Feb 14 02:45:09 2017 728241 Setread_only on the new master.. ok.
Tue Feb 14 02:45:09 2017 733969 Drpping appuser on the orig master..
Tue Feb 14 02:45:09 2017 735861 Set read_only=1on the orig master.. ok.
Tue Feb 14 02:45:09 2017 739394 Killing allapplication threads..
Tue Feb 14 02:45:09 2017 739431 done.
SIOCSIFFLAGS: Cannot assign requestedaddress
Tue Feb 14 02:45:09 2017 - [info]  ok.
Tue Feb 14 02:45:09 2017 - [info] Lockingall tables on the orig master to reject updates from everybody (includingroot):
Tue Feb 14 02:45:09 2017 - [info] ExecutingFLUSH TABLES WITH READ LOCK..
Tue Feb 14 02:45:09 2017 - [info]  ok.
Tue Feb 14 02:45:09 2017 - [info] Origmaster binlog:pos is single-mysql-bin.000009:997.
Tue Feb 14 02:45:09 2017 - [info]  Waiting to execute all relay logs on10.192.203.201(10.192.203.201:3306)..
Tue Feb 14 02:45:09 2017 - [info]  master_pos_wait(single-mysql-bin.000009:997)completed on 10.192.203.201(10.192.203.201:3306). Executed 0 events.
Tue Feb 14 02:45:09 2017 - [info]   done.
Tue Feb 14 02:45:09 2017 - [info] Gettingnew master's binlog name and position..
Tue Feb 14 02:45:09 2017 - [info]  single-mysql-bin.000022:107
Tue Feb 14 02:45:09 2017 - [info]  All other slaves should start replicationfrom here. Statement should be: CHANGE MASTER TO MASTER_HOST='10.192.203.201',MASTER_PORT=3306, MASTER_LOG_FILE='single-mysql-bin.000022', MASTER_LOG_POS=107,MASTER_USER='rep_user', MASTER_PASSWORD='xxx';
Tue Feb 14 02:45:09 2017 - [info] Executingmaster ip online change script to allow write on the new master:
Tue Feb 14 02:45:09 2017 - [info]   /usr/bin/master_ip_online_change--command=start --orig_master_host=10.192.203.101 --orig_master_ip=10.192.203.101--orig_master_port=3306 --orig_master_user='mha' --orig_master_password='test'--new_master_host=10.192.203.201 --new_master_ip=10.192.203.201--new_master_port=3306 --new_master_user='mha' --new_master_password='test'--orig_master_ssh_user=root --new_master_ssh_user=root   --orig_master_is_new_slave
Tue Feb 14 02:45:09 2017 946501 Setread_only=0 on the new master.
Tue Feb 14 02:45:09 2017 947009 Creatingapp user on the new master..
Tue Feb 14 02:45:10 2017 - [info]  ok.
Tue Feb 14 02:45:10 2017 - [info]
Tue Feb 14 02:45:10 2017 - [info] *Switching slaves in parallel..
Tue Feb 14 02:45:10 2017 - [info]
Tue Feb 14 02:45:10 2017 - [info] -- Slaveswitch on host 10.192.203.102(10.192.203.102:3306) started, pid: 8353
Tue Feb 14 02:45:10 2017 - [info]
Tue Feb 14 02:45:10 2017 - [info] Logmessages from 10.192.203.102 ...
Tue Feb 14 02:45:10 2017 - [info]
Tue Feb 14 02:45:10 2017 - [info]  Waiting to execute all relay logs on10.192.203.102(10.192.203.102:3306)..
Tue Feb 14 02:45:10 2017 - [info]  master_pos_wait(single-mysql-bin.000009:997)completed on 10.192.203.102(10.192.203.102:3306). Executed 0 events.
Tue Feb 14 02:45:10 2017 - [info]   done.
Tue Feb 14 02:45:10 2017 - [info]  Resetting slave10.192.203.102(10.192.203.102:3306) and starting replication from the newmaster 10.192.203.201(10.192.203.201:3306)..
Tue Feb 14 02:45:10 2017 - [info]  Executed CHANGE MASTER.
Tue Feb 14 02:45:10 2017 - [info]  Slave started.
Tue Feb 14 02:45:10 2017 - [info] End oflog messages from 10.192.203.102 ...
Tue Feb 14 02:45:10 2017 - [info]
Tue Feb 14 02:45:10 2017 - [info] -- Slaveswitch on host 10.192.203.102(10.192.203.102:3306) succeeded.
Tue Feb 14 02:45:10 2017 - [info] Unlockingall tables on the orig master:
Tue Feb 14 02:45:10 2017 - [info] ExecutingUNLOCK TABLES..
Tue Feb 14 02:45:10 2017 - [info]  ok.
Tue Feb 14 02:45:10 2017 - [info] Startingorig master as a new slave..
Tue Feb 14 02:45:10 2017 - [info]  Resetting slave10.192.203.101(10.192.203.101:3306) and starting replication from the newmaster 10.192.203.201(10.192.203.201:3306)..
Tue Feb 14 02:45:10 2017 - [info]  Executed CHANGE MASTER.
Tue Feb 14 02:45:10 2017 - [info]  Slave started.
Tue Feb 14 02:45:10 2017 - [info] All newslave servers switched successfully.
Tue Feb 14 02:45:10 2017 - [info]
Tue Feb 14 02:45:10 2017 - [info] * Phase5: New master cleanup phase..
Tue Feb 14 02:45:10 2017 - [info]
Tue Feb 14 02:45:10 2017 - [info]  10.192.203.201: Resetting slave infosucceeded.
Tue Feb 14 02:45:10 2017 - [info] Switchingmaster to 10.192.203.201(10.192.203.201:3306) completed successfully.

 

中间需要手动输入两个yes。

 

10.3 检查是否切换成功

执行masterha_check_repl --conf=/etc/mha/app1.cnf验证下当前主从配置是否正确。

登录各从库,验证下现在复制是否已指向新的主库。

现在10.192.203.101, 10.192.203.102复制都指向10.192.203.201.

10.192.203.201上没有复制信息:

mysql> show slave status \G;

Empty set (0.00 sec)

 

ERROR:

No query specified

 

发现在线切换后有如下特点:

①  :在线切换完成后,其他库复制都会指向现在的主库。现在的主库上原先的复制信息被清除

②  :mha配置文件里原先主库的信息没有被删除。

③  :原先的主库自动变成只读,现在的主库自动变成可写。

④  :原来主库上的vip自动漂移到了现在的主库上。

10.4 后续操作

①:在线切换完成后,现在的主库仍然需要change master to原先的主库,然后开始复制。

②  :启动原先主库的keepalive进程

③:启动mha监控

 

我发现当备用主库宕机后,假如主库也宕掉了,此时mha无法自动切换到其他slave上。错误日志:

Wed Feb 15 21:42:04 2017 -[error][/usr/share/perl5/vendor_perl/MHA/ServerManager.pm, ln492]  Server 10.192.203.101(10.192.203.101:3306) isdead, but must be alive! Check server settings.

Wed Feb 15 21:42:04 2017 -[error][/usr/share/perl5/vendor_perl/MHA/ManagerUtil.pm, ln177] Got ERROR:  at/usr/share/perl5/vendor_perl/MHA/MasterFailover.pm line 268

 

--本篇文章参考了:http://www.cnblogs.com/xuanzhi201111/p/4231412.html

--文章如有不当之处,欢迎指出!

你可能感兴趣的:(1,MySql,学习,#,Mysql,主从复制,#,MySql,高可用)