mha 0.58 gtid模式下 丢数据问题修复

问题描述：

在gtid模式下 ，mha发生故障切换 ，如果Linux主机还存活 ，不会去比对master的日志，获取差异日志 ，有导致数据丢失的风险 。

问题修复：

找到 MasterFailover.pm 文件 ，将下文！ 去掉

    if ( !$_server_manager->is_gtid_auto_pos_enabled() ) {      $log->info();      $log->info("* Phase 3.2: Saving Dead Master's Binlog Phase..\n");      $log->info();      save_master_binlog($dead_master);    }

去掉后的代码

    if ( $_server_manager->is_gtid_auto_pos_enabled() ) {      $log->info();      $log->info("* Phase 3.2: Saving Dead Master's Binlog Phase..\n");      $log->info();      save_master_binlog($dead_master);    }

找到 apply_binlog_to_master 函数定义的位置

sub apply_binlog_to_master($) {  my $target   = shift;  my $err_file = "$g_workdir/mysql_from_binlog.err";  my $command ="cat $_diff_binary_log  | mysql --binary-mode --user=$target->{mysql_escaped_user} --password=$target->{mysql_escaped_password} --host=$target->{ip} --port=$target->{port} -vvv --unbuffered > $err_file 2>&1";  $log->info("Checking if super_read_only is defined and turned on..");  my ($super_read_only_enabled, $dbh) =          MHA::SlaveUtil::check_if_super_read_only($target->{hostname}, $target->{ip}, $target->{port}, $target->{user}, $target->{password});  if ($super_read_only_enabled) {    MHA::SlaveUtil::disable_super_read_only($dbh);  } else {    $log->info(" not present or turned off, ignoring.\n");  }

修改后的代码 cat $_diff_binary_log

sub apply_binlog_to_master($) {  my $target   = shift;  my $err_file = "$g_workdir/mysql_from_binlog.err";  my $command ="mysqlbinlog $_diff_binary_log --skip-gtids=true | mysql --binary-mode --user=$target->{mysql_escaped_user} --password=$target->{mysql_escaped_password} --host=$target->{ip} --port=$target->{port} -vvv --unbuffered > $err_file 2>&1";  $log->info("Checking if super_read_only is defined and turned on..");  my ($super_read_only_enabled, $dbh) =          MHA::SlaveUtil::check_if_super_read_only($target->{hostname}, $target->{ip}, $target->{port}, $target->{user}, $target->{password});  if ($super_read_only_enabled) {    MHA::SlaveUtil::disable_super_read_only($dbh);  } else {    $log->info(" not present or turned off, ignoring.\n");  }