再谈MysqlMHA

关于Mysql数据库的高可用以及mysql的proxy中间件的选型一直是个很活跃的技术话题。以高可用为例，解决方案有mysqlndb集群，mmm,mha,drbd等多种选择。Mysql的prox

# ssh-keygen # ssh-copy-id -i /root/.ssh/id_rsa.pub root@192.168.1.12 # ssh-copy-id -i /root/.ssh/id_rsa.pub root@192.168.1.225 # ssh-copy-id -i /root/.ssh/id_rsa.pub root@192.168.1.226 # ssh-copy-id -i /root/.ssh/id_rsa.pub root@192.168.1.227

Rpm包下载地址，需要翻墙： https://code.google.com/p/mysql-master-ha/downloads/detail?name=mha4mysql-manager-0.53-0.el6.noarch.rpm https://code.google.com/p/mysql-master-ha/downloads/detail?name=mha4mysql-node-0.52-0.noarch.rpm 管理节点： # yum -y localinstall \ mha4mysql-node-0.52-0.noarch.rpm \ mha4mysql-manager-0.53-0.el6.noarch.rpm 数据库节点： # yum -y localinstall mha4mysql-node-0.52-0.noarch.rpm

3: 配置mha主配置文件

管理节点： # mkdir -p /usr/local/mha # mkdir -p /etc/mha # cat /etc/mha/mha.conf [server default] user=root password=123456 manager_workdir=/usr/local/mha manager_log=/usr/local/mha/manager.log remote_workdir=/usr/local/mha ssh_user=root repl_user=replication repl_password=123456 ping_interval=1 secondary_check_script= masterha_secondary_check -s 192.168.1.226 -s 192.168.1.227 master_ip_failover_script=/usr/local/scripts/master_ip_failover [server1] hostname=192.168.1.225 ssh_port=22 master_binlog_dir=/mydata candidate_master=1 [server2] hostname=192.168.1.226 ssh_port=22 master_binlog_dir=/mydata candidate_master=1 [server3] hostname=192.168.1.227 ssh_port=22 master_binlog_dir=/mydata no_master=1

4：准备failover脚本

# cat /usr/local/scripts/master_ip_failover

#!/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 = '192.168.1.231'; # Virtual IP my $gateway = '192.168.1.1';#Gateway IP my $interface = 'eth0'; my $key = "1"; my $ssh_start_vip = "/sbin/ifconfig $interface:$key $vip;/sbin/arping -I $interface -c 3 -s $vip $gateway >/dev/null 2>&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; } 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"; }

# masterha_check_ssh --conf=/etc/mha/mha.conf

# cp -rvp /usr/lib/perl5/vendor_perl/MHA /usr/local/lib64/perl5/

（mha的数据库节点和管理节点均需要执行此步骤）

# masterha_check_ssh --conf=/etc/mha/mha.conf

6：进行同步检查