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CentOS6.5x86_64
MySQL5.6.34編譯安裝版
MHA版本：mha4mysql-manager-0.56-0.el6.noarch.rpm mha4mysql-node-0.56-0.el6.noarch.rpm
節(jié)點角色：
node93：10.1.20.93 默認(rèn)主庫
node94：10.1.20.94 從庫1，原先主庫宕機后可提升為主庫【mha管理節(jié)點也部署在這臺機器上】
node95：10.1.20.95 從庫2，不允許提升為主庫
準(zhǔn)備的VIP是 10.1.20.100/24
step1、配置主從關(guān)系
node93的/etc/my.cnf配置文件部分關(guān)鍵地方：
[mysqld]
port = 3306
socket = /tmp/mysql.sock
datadir = /bdata/data/nowdb2
innodb_file_per_table=ON
character-set-server = utf8
default_storage_engine = InnoDB
skip-innodb_adaptive_hash_index
master_info_repository = TABLE
relay_log_info_repository = TABLE
relay_log_recovery = 1 #crash safe
log-bin=mysql-bin
binlog_format=row
sync_binlog =1 #確保事務(wù)提交的時候BINLOG落盤
log-slave-updates
log_bin_trust_function_creators =1
binlog_rows_query_log_events=ON #記錄執(zhí)行的語句到BINLOG query event
server-id=1020093
relay_log_purge=0
read_only=1
node94的/etc/my.cnf配置文件部分關(guān)鍵地方：
[mysqld]
port = 3306
socket = /tmp/mysql.sock
datadir = /bdata/data/nowdb2
innodb_file_per_table=ON
character-set-server = utf8
default_storage_engine = InnoDB
skip-innodb_adaptive_hash_index
master_info_repository = TABLE
relay_log_info_repository = TABLE
relay_log_recovery = 1 #crash safe
log-bin=mysql-bin
binlog_format=row
sync_binlog =1 #確保事務(wù)提交的時候BINLOG落盤
log-slave-updates
log_bin_trust_function_creators =1
binlog_rows_query_log_events=ON #記錄執(zhí)行的語句到BINLOG query event
server-id=1020094
relay_log_purge=0
read_only=1
node95的/etc/my.cnf配置文件部分關(guān)鍵地方：
[mysqld]
port = 3306
socket = /tmp/mysql.sock
datadir = /bdata/data/nowdb2
innodb_file_per_table=ON
character-set-server = utf8
default_storage_engine = InnoDB
skip-innodb_adaptive_hash_index
master_info_repository = TABLE
relay_log_info_repository = TABLE
relay_log_recovery = 1 #crash safe
log-bin=mysql-bin
binlog_format=row
sync_binlog =1 #確保事務(wù)提交的時候BINLOG落盤
log-slave-updates
log_bin_trust_function_creators = 1
binlog_rows_query_log_events=ON #記錄執(zhí)行的語句到BINLOG query event
server-id=1020095
relay_log_purge=0
read_only=1
在node93上創(chuàng)建復(fù)制權(quán)限的賬號，GRANT REPLICATION SLAVE ,REPLICATION CLIENT ON *.* TO 'rpl'@'10.1.%.%' IDENTIFIED BY 'rpl';
然后配置1主2從，（具體步驟略過）。
注意：我們要確保能成為主庫的節(jié)點(node93、node94)都存在主從同步賬號，如果node94上不存在rpl賬號，就到node94節(jié)點去手工添加即可。
主從關(guān)系建立好后，我們在master上創(chuàng)建個mha管理賬號，后期會用到：
grant all on *.* to 'mhauser'@'10.1.%.%' identified by 'Abcd@1234';
(管理賬號要在node93、node94、node95所有節(jié)點都存在)
step2、安裝MHA
因為MHA依賴于SSH，因此需要在3臺主機之間建立SSH免秘鑰登陸。步驟略過。
3個節(jié)點都安裝perl包：
yum install perl perl-DBD-MySQL perl-CPAN perl-devel perl-Time-HiRes
node93-node95上都安裝node包：
rpm -ivh mha4mysql-node-0.56-0.el6.noarch.rpm
node94上安裝Manager包(當(dāng)然，我們在3個節(jié)點都安裝上Manager包也沒問題)：
rpm -ivh mha4mysql-manager-0.56-0.el6.noarch.rpm
在node94初始化MHA
mkdir /etc/masterha/
vim /etc/masterha/app1.cnf內(nèi)容如下：
[server default]
user=mhauser
password=Abcd@1234
manager_workdir=/data/masterha/app1
manager_log=/data/masterha/app1/manager.log
remote_workdir=/data/masterha/app1
ssh_user=root
repl_user=rpl
repl_password=rpl
ping_interval=1
master_binlog_dir=/bdata/data/nowdb2/ #這個路徑和你的mysql的binlog存放路徑要一致
master_ip_failover_script=/etc/masterha/master_ip_failover
report_script=/etc/masterha/send_report
#通過第三方機器確認(rèn)目標(biāo)主庫是否存活,不是必須的,就算沒有也是能用
#secondary_check_script=masterha_secondary_check -s remote_host1 -s remote_host2
#故障發(fā)生后關(guān)閉主機的腳本,不是必須的,但是你要設(shè)置為空
# shutdown_script=""
#手動在線切換VIP腳本,不是必須的,就算沒有也是能用,
#如果你有keepalived這種來做切換VIP就可以直接不用了
master_ip_online_change_script==/etc/masterha/master_ip_online_change
[server1]
hostname=10.1.20.93
candidate_master=1
[server2]
hostname=10.1.20.94
candidate_master=1
[server3]
hostname=10.1.20.95
no_master=1 # 禁止
在node94上添加腳本/etc/masterha/master_ip_failover (里面填寫上相關(guān)的VIP的信息)
#!/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,
$orig_master_ssh_port, $new_master_ssh_port
);
my $vip ='10.1.20.100'; # Virtual IP
my $devic='eth0';
my $key = "0";
my$net_mask='255.255.255.0';
my $ssh_start_vip ="/sbin/ifconfig $devic:$key $vip netmask $net_mask";
my $ssh_stop_vip ="/sbin/ifconfig $devic:$key down";
my$mysql_conf="/etc/my.cnf";
my $open_readonly="/bin/sed-i 's/.*read_only.*/read_only=1/g' $mysql_conf ";
my $close_readonly="/bin/sed-i 's/.*read_only.*/read_only=0/g' $mysql_conf ";
my $open_relaylog_purge="/bin/sed-i 's/.*relay_log_purge.*/relay_log_purge=0/g' $mysql_conf ";
my$close_relaylog_purge="/bin/sed -i's/.*relay_log_purge.*/relay_log_purge=0/g' $mysql_conf ";
GetOptions(
'command=s' =>\$command,
'ssh_user=s' =>\$ssh_user,
'orig_master_host=s' => \$orig_master_host,
'orig_master_ip=s' =>\$orig_master_ip,
'orig_master_port=i' => \$orig_master_port,
'orig_master_ssh_port=i' => \$orig_master_ssh_port,
'new_master_host=s' => \$new_master_host,
'new_master_ip=s' =>\$new_master_ip,
'new_master_port=i' =>\$new_master_port,
'new_master_ssh_port=i' => \$new_master_ssh_port,
);
exit &main();
sub main {
print "\n\nIN SCRIPTTEST====$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 atglobal catalog database,
# invalidate orig_master_ip here.
my $exit_code = 1;
eval {
print "Disabling the VIP onold 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 atglobal 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 - $vipon 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 thescript.. OK \n";
# `ssh $ssh_user\@cluster1 \"$ssh_start_vip \"`;
exit 0;
}
else {
&usage();
exit 1;
}
}
# A simple system call that enablethe VIP on the new master
sub start_vip() {
`ssh $ssh_user\@$new_master_host \" $ssh_start_vip \"`;
print "Disable read_only and relay_log_purge in my.cnf - on the new master - $new_master_host\n";
`ssh $ssh_user\@$new_master_host \" $close_readonly \"`;
`ssh $ssh_user\@$new_master_host \" $close_relaylog_purge \"`;
}
# A simple system call thatdisable the VIP on the old_master
sub stop_vip() {
`ssh $ssh_user\@$orig_master_host \" $ssh_stop_vip \"`;
print "Enable read_only and relay_log_purge in my.cnf - on the orig master - $orig_master_host\n";
`ssh $ssh_user\@$orig_master_host \" $open_readonly \"`;
`ssh $ssh_user\@$orig_master_host \" $open_relaylog_purge \"`;
}
sub usage {
"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--orig_master_ssh_port=ssh_port --new_master_ssh_port = ssh_port\n";
}
在node94上添加腳本/etc/masterha/send_report(里面填寫上相關(guān)的smtp賬號的信息)：
#!/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 scriptand 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_hostsare set only when recovering master succeeded
my ( $dead_master_host,$new_master_host, $new_slave_hosts, $subject, $body ,$conf);
my$smtp='smtp.exmail.qq.com';
my$mail_from='zabbix@xxxx.com';
my$mail_user='zabbix@xxxx.com';
my $mail_pass='xxxxxxx';
my$mail_to=['lixxxx@xxxx.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,
'conf=s' => \$conf,
);
mailToContacts($smtp,$mail_from,$mail_user,$mail_pass,$mail_to,$subject,$body);
check_if_sendmail_ok('/tmp/monitormail.log');
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 $Mail::Sender::Error;
return 1;
}
sub check_if_sendmail_ok{
#>>250 2.0.0 Ok: queued as 3532C6DA009D
#< #>>221 2.0.0 Bye my$logf = shift; openRLOG, $logf or die "cannot open file $logf.\n"; my@log = closeRLOG; my$val = 0; if($log[$#log]=~ m/\>\>\s221\s.*\sBye/){ print"Meet Bye.\t"; $val++; } if($log[$#log-1]=~ m/\<\<\sQUIT/){ print"Meet QUIT.\t"; $val++; } if($log[$#log-2]=~ m/\>\>\s250\s.*\sOk: queued/){ print"Meet queued.\t"; $val++; } print"\n"; if($val== 3){ print"send mail success.\n"; } else{ print"send mail failed.check DNS/SMTP config\n"; } return$val; } # Do whatever you want here exit 0; 在node94上添加腳本/etc/masterha/master_ip_online_change(里面填寫上相關(guān)的VIP的信息)： #!/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 scriptand 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( sleepgettimeofday tv_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 ='10.1.20.100/24'; my $key = '0'; my $ssh_start_vip ="/sbin/ifconfig eth0:$key $vip"; my $ssh_stop_vip ="/sbin/ifconfig eth0:$key down"; 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 = newMHA::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() . " Setread_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 ifany database error happens my $orig_master_handler = newMHA::DBHelper(); $orig_master_handler->connect($orig_master_ip, $orig_master_port, $orig_master_user,$orig_master_password, 1 ); ## Drop application user so that nobodycan connect. Disabling per-session binlog beforehand $orig_master_handler->disable_log_bin_local(); print current_time_us() . " Drppingapp user on the orig master..\n"; #FIXME_xxx_drop_app_user($orig_master_handler); ## Waiting for N * 100 milliseconds sothat 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 %dthreads are disconnected.. (max %d milliseconds)\n", current_time_us(), $#threads + 1,$time_until_read_only * 100; if ( $#threads < 5 ) { printData::Dumper->new( [$_] )->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 currentmaster so that nobody(except SUPER) can write print current_time_us() . " Setread_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 sothat 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 %dqueries 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} ); } ## Terminating all threads print current_time_us() . " Killingall 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(); $orig_master_handler->disconnect(); ## After finishing the script, MHAexecutes FLUSH TABLES WITH READ LOCK eval { `ssh -p$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 eventhough activating updatable accounts/ip failed so that we don't interruptslaves' recovery. # If exit code is 0 or 10, MHAdoes not abort my $exit_code = 10; eval { my $new_master_handler = newMHA::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"; $new_master_handler->disable_read_only(); ## Creating an app user on the new master print current_time_us() . " Creatingapp user on the new master..\n"; #FIXME_xxx_create_app_user($new_master_handler); $new_master_handler->enable_log_bin_local(); $new_master_handler->disconnect(); ## Update master ip on the catalogdatabase, etc `ssh -p$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; } 在node94上檢查MHA的SSH是否配置無誤： masterha_check_ssh--conf=/etc/masterha/app1.cnf 如能出現(xiàn)"All SSH connection tests passedsuccessfully."說明配置沒問題 在node94上檢查MHA的主從復(fù)制是否配置無誤： masterha_check_repl--conf=/etc/masterha/app1.cnf 如提示"MySQL Replication Health is OK"說明配置沒問題 在node94上前臺啟動MHA： masterha_manager--conf=/etc/masterha/app1.cnf --ignore_last_failover 在前臺啟動監(jiān)控 模擬node93master宕機、觀察master的自動切換： 將node93的mysql服務(wù)停掉，可以發(fā)現(xiàn)此時node94上開啟的masterha_manager進程自動退出了，到其他節(jié)點去查看，可以發(fā)現(xiàn)主從切換了。 然后啟動node93的mysql，再次上線就不會自動變成master 【!!注意：直接將node93上線的話，集群中就出現(xiàn)了2個主節(jié)點，腦裂，masterha_manger也無法啟動】，我們需要先手工將其改為從節(jié)點，操作如下： 在node93上，執(zhí)行： > change master to master_host='10.1.20.94', master_user='rpl', master_password='rpl', master_log_file='mysql-bin.000003', master_log_pos=1881; #這里的位置，需要看下node94的/data/masterha/app1目錄下的manager.log里面的內(nèi)容找到具體的binlog位置。 > start slave; > show slave status\G 將node93重新加入集群后，我們在node94 manager節(jié)點上再次執(zhí)行 masterha_manager--conf=/etc/masterha/app1.cnf --ignore_last_failover 發(fā)現(xiàn)啟動不退出了。(驗證過程中不要關(guān)閉這個窗口) 檢查下當(dāng)前主從的配置： node94另外開一個xshell窗口，可以執(zhí)行 masterha_check_repl--conf=/etc/masterha/app1.cnf 可以看出主節(jié)點、從節(jié)點的發(fā)生了變化: 查看是否masterha啟動： 另外開一個xshell窗口，可以執(zhí)行 masterha_check_status--conf=/etc/masterha/app1.cnf 如果需要停止masterha的話，不要用stop或者kill，要用下面的命令： masterha_stop--conf=/etc/masterha/app1.cnf 手動切換主從的方法： masterha_master_switch-h 查看幫助信息 masterha_master_switch--conf=/etc/masterha/app1.cnf --master_state=alive --new_master_host=10.1.20.93--new_master_port=3306 --orig_master_is_new_slave --running_updates_limit=10000 手工切換的時候需要注意2點: 1、執(zhí)行手工切換的時候，需要先關(guān)掉老的master和即將提升為master的主機的 event scheduler，否則無法切換(set global event_scheduler = OFF;) 2、執(zhí)行手工切換的時候，需要先關(guān)閉MHA的監(jiān)控 masterha_stop--conf=/etc/masterha/app1.cnf ) 3、執(zhí)行手工切換腳本的時候，它會自動在原先的master上執(zhí)行FLUSH TABLES WITH READ LOCK;等切換完成后，再UNLOCK TABLES釋放掉這個原有master的鎖。 發(fā)送郵件的腳本，需要先安裝插件： yuminstall perl-Mail-Sender 發(fā)送失敗的話，可以查看/tmp/monitormail.log找找失敗的原因。 MHA異常的話： 可以查看日志路徑：/data/masterha/app1/ masterha_manager還有幾個比較有用的啟動參數(shù)： --remove_dead_master_conf 該參數(shù)代表當(dāng)發(fā)生主從切換后，老的主庫的ip將會從配置文件中移除。 --manger_log 日志存放位置,想規(guī)范化管理日志可以加上 --ignore_last_failover 該參數(shù)代表忽略上次MHA觸發(fā)切換產(chǎn)生的文件，默認(rèn)情況下，MHA發(fā)生切換后會在日志目錄，也就是上面我設(shè)置的/data產(chǎn)生app1.failover.complete文件，下次再次切換的時候如果發(fā)現(xiàn)該目錄下存在該文件將不允許觸發(fā)切換，除非在第一次切換后收到刪除該文件，在缺省情況下，如果MHA檢測到連續(xù)發(fā)生宕機，且兩次宕機間隔不足8小時的話，則不會進行Failover，之所以這樣限制是為了避免ping-pong效應(yīng)。【如果我們需要強制切換的話，需要先移除這個文件app1.failover.complete】 
網(wǎng)站標(biāo)題：MHA部署筆記(centos6+mysql5.6)
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