MHA高可用架构
- 用一个管理节点监控后端数据库主库可用性
- 提供VIP漂移接口，不提供具体方法
- 提供补全从库日志的脚本
MHA
- 监控主库，提供自动主从切换；
- 提供VIP漂移接口
- 提供补全从库日志的脚本
MHA的安装步骤
- 规划
- 配置服务器间域名和ssh互信访问
- 在manager节点安装MHA node 和manager组件及依赖包
- 在数据库服务器安装MHA node组件及依赖包
- 配置VIP管理脚本master_ip_failover和master_ip_online_change
- 配置MHA配置文件mha_manager.cnf
- 数据库配置主从，添加mha连接用户 ...etc
- 启动MHA开始监控数据库主从集群
演示
演示MHA部署-环境介绍
环境请自行提取下载
http://pan.baidu.com/s/1qXDOeba
操作步骤
操作步骤： - 0.确保主从复制配置完成 - 此列中主从复制账号repl - - ## - - 虚拟ip已经，部署在主库 - 主库，为mha提供mha账户 - - - - - 1.确保hosts和hostname配置正确 - ## - - root@debtest1:~/.ssh# cat /etc/hosts - 127.0.0.1 localhost - 192.168.0.113 debtest1.sam.test debtest1 - 192.168.0.114 debtest2.sam.test debtest2 - 192.168.0.115 debtest3.sam.test debtest3 - - # The following lines are desirable for IPv6 capable hosts - ::1 localhost ip6-localhost ip6-loopback - ff02::1 ip6-allnodes - ff02::2 ip6-allrouters - root@debtest1:~/.ssh# cat /etc/hostname - debtest1 - - ############################################################################### - - 2.使用ssh-keygen工具生成统一公私钥对,并同步到所有三台机器.测试公私钥验证访问 - ## - - ssh-keygen -t rsa - - cd ~/.ssh - cat id_rsa.pub authorized_keys - - - scp ./* root@debtest2:/root/.ssh/ - scp ./* root@debtest3:/root/.ssh/ - - - ssh debtest1 - ssh debtest2 - ssh debtest3 - - - ############################################################################### - - 3.规划节点用户和ip配置 - ## - - - 192.168.0.113 debtest1 --> master - 192.168.0.114 debtest2 --> mysql1(master) - 192.168.0.115 debtest3 --> mysql2(slave) - 192.168.0.119 vip - - 定好虚拟ip后别忘了在当前的主库上添加虚拟ip - ## - ip addr add 192.168.0.119/32 dev eth1 - - #删除虚拟ip的命令 - ##ip addr del 192.168.0.119/32 dev eth1 - - ############################################################################### - - 4.在全部节点上安装mha node包和其依赖包 - ## - - - debtest1,debtest1,debtest1 - - apt-get install libdbd-mysql-perl - - dpkg -i mha4mysql-node_0.53_all.deb - - ############################################################################### - - 5.仅需要在manager节点上安装mha manager包及其依赖包 - ## - - debtest1 - - apt-get install libdbd-mysql-perl - apt-get install libconfig-tiny-perl - apt-get install liblog-dispatch-perl - apt-get install libparallel-forkmanager-perl - - dpkg -i mha4mysql-manager_0.53_all.deb - - - ############################################################################### - - - 6.建立配置文件目录,编辑mha必要的三个文件,一个配置文件,2个虚拟ip管理脚本且内容可以一致 - ## - - master_ip_online_change - master_ip_failover - mha_manager.cnf - - - ############################################################################### - - 7.可以尝试验证一下配置是否成功 - ## - - masterha_check_ssh --conf=./mha_manager.cnf - masterha_check_repl --conf=./mha_manager.cnf - - ############################################################################### - - 8.在manager节点启动mha服务,然后观察日志,并尝试关闭当前主库,注意观察日志,主要看失效发现,日志检测,ip漂移和角色切换过程 - ## - - nohup /usr/bin/masterha_manager --conf=/root/mha_base/mha_manager.cnf --ignore_last_failover < /dev/null > /root/mha_base/manager.log 2>&1 &
MHA配置文件
MHA配置文件 [server default] manager_workdir=/root/mha_base manager_log=/root/mha_base/manager.log remote_workdir=/root/mha_base ssh_user=root ssh_port=22 user=mha password=mha repl_user=repl repl_password=repl multi_tier_slave=1 ping_interval=1 ping_type=CONNECT master_ip_failover_script=/root/mha_base/master_ip_failover master_ip_online_change_script=/root/mha_base/master_ip_online_change secondary_check_script=/usr/bin/masterha_secondary_check -s 192.168.0.113 -s 192.168.0.115 --user=root --port=22 --master_host=debtest2 --master_ip=192.168.0.114 --master_port=3306 [server1] candidate_master=0 ignore_fail=1 check_repl_delay = 1 hostname=debtest2 ip=192.168.0.114 port=3306 ssh_port=22 master_binlog_dir=/var/log/mysql/ [server2] candidate_master=0 ignore_fail=1 check_repl_delay = 1 hostname=debtest3 ip=192.168.0.115 port=3306 ssh_port=22 master_binlog_dir=/var/log/mysql/
VIP漂移脚本
#!/usr/bin/env perl ## 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; my ( $command, $ssh_user, $orig_master_host, $orig_master_ip, $orig_master_port, $new_master_host, $new_master_ip, $new_master_port ); my $vip = '192.168.0.119/24'; #virtual ip my $ssh_start_vip = "ip addr add $vip dev eth1"; my $ssh_stop_vip = "ip addr del $vip dev eth1"; 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 { 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(); $exit_code = 0; # updating global catalog, etc }; if ($@) { 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 old master: $new_master_host \n"; &start_vip(); $exit_code = 0; }; if ($@) { warn $@; # If you want to continue failover, exit 10. exit $exit_code; } exit $exit_code; } elsif ( $command eq "status" ) { # do nothing exit 0; } else { &usage(); exit 1; } } # Enable the VIP on the new_master sub start_vip() { `ssh $ssh_user\@$new_master_host \" $ssh_start_vip \"`; } # Disable the VIP on the old_master sub stop_vip() { my $ssh_user = "root"; `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"; }
