摘要：高可用环境角色主机名类型主从节点写从节点读从节点读无管理节点一环境部署更改主机名，添加文件分发给其他主机配置密钥所有主机各配置相同操作例如在所有主机都必须拷贝密钥于其他主机拷贝密钥测试登录关闭防火墙以及集群主机时间同步安装环
MySQL高可用MHA
环境：
| 角色 | IP | 主机名 | Server ID | 类型 |
|---|---|---|---|---|
| master1 | 192.168.1.12 | master1 | 1 | 主从节点写 |
| master2 | 192.168.1.13 | master2 | 2 | 从节点读 |
| slave | 192.168.1.14 | slave | 3 | 从节点读 |
| manager | 192.168.1.7 | manager | 无 | 管理节点 |
①更改主机名，添加hosts文件
[root@192 ~]# hostnamectl set-hostname master1
[root@192 ~]# hostnamectl set-hostname master2
[root@192 ~]# hostnamectl set-hostname slave
[root@192 ~]# hostnamectl set-hostname manager
[root@master1 ~]# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4 ::1 localhost localhost.localdomain localhost6 localhost6.localdomain6 192.168.1.12 master1 192.168.1.13 master2 192.168.1.14 slave 192.168.1.7 manager
[root@master1 ~]# for i in master2 slave manager ; do scp /etc/hosts $i:/etc/hosts;done
分发给其他主机
②配置密钥ssh(所有主机各配置相同操作)
例如master1：
[root@master1 ~]# ssh-keygen -t rsa
在所有主机都必须拷贝密钥于其他主机
[root@master1 ~]# for i in master1 master2 slave manager ; do ssh-copy-id $i ; done
拷贝密钥
[root@master1 ~]# for i in master1 master2 slave manager ; do ssh $i hostname ; done
测试登录
③关闭防火墙以及selinx
④集群主机时间同步
⑤安装环境插件
[root@192 ~]# yum -y install epel-release
[root@192 ~]# yum -y install perl-DBD-MySQL perl-Config-Tiny perl-Log-Dispatch perl-Parallel-ForkManager perl-Config-IniFiles ncftp perl-Params-Validate perl-CPAN perl-Test-Mock-LWP.noarch perl-LWP-Authen-Negotiate.noarch perl-devel perl-ExtUtils-CBuilder perl-ExtUtils-MakeMaker
步骤：
①检查mysql状态
mysql半同步是由谷歌提供，master是semisync_master.so，slave是semisync_slave.so，如不清楚路径可以先进行查询
mysql> show variables like "%plugin_dir%";
| Variable_name | Value |
|---|---|
| plugin_dir | /usr/local/mysql/lib/plugin/ |
再进行检查是否支持动态载入
mysql> show variables like "%have_dynamic_loading%";
| Variable_name | Value |
|---|---|
| have_dynamic_loading | YES |
②安装mysql半同步插件(在所有的mysql主机)
mysql> install plugin rpl_semi_sync_master soname "semisync_master.so";
mysql> install plugin rpl_semi_sync_slave soname "semisync_slave.so";
检查是否正确安装
mysql> show plugins;
| rpl_semi_sync_master | ACTIVE | REPLICATION | semisync_master.so | GPL |
|---|---|---|---|---|
| rpl_semi_sync_slave | ACTIVE | REPLICATION | semisync_slave.so | GPL |
查看半同步相关信息
mysql> show variables like "rpl_semi_sync%";
| Variable_name | Value |
|---|---|
| rpl_semi_sync_master_enabled | OFF |
| rpl_semi_sync_master_timeout | 10000 |
| rpl_semi_sync_master_trace_level | 32 |
| rpl_semi_sync_master_wait_for_slave_count | 1 |
| rpl_semi_sync_master_wait_no_slave | ON |
| rpl_semi_sync_master_wait_point | AFTER_SYNC |
| rpl_semi_sync_slave_enabled | OFF |
| rpl_semi_sync_slave_trace_level | 32 |
③配置mysql半同步复制
master1:
[root@master1 ~]# cat /etc/my.cnf
[mysqld] basedir = /usr/local/mysql datadir = /usr/local/mysql/data port = 3306 server_id = 1 socket = /usr/local/mysql/mysql.sock log-error=/usr/local/mysql/data/mysqld.err log-bin = mysql-bin log-bin-index = mysql-bin.index rpl_semi_sync_master_enabled = 1 rpl_semi_sync_master_timeout = 1000 rpl_semi_sync_slave_enabled = 1 relay_log_purge = 0 relay-log = relay-bin relay-log-index = slave-relay-bin.index [client] host = 127.0.0.1 user = root password = 123.com
master2:
[root@master2 ~]# cat /etc/my.cnf
[mysqld] basedir = /usr/local/mysql datadir = /usr/local/mysql/data port = 3306 server_id = 2 socket = /usr/local/mysql/mysql.sock log-error=/usr/local/mysql/data/mysqld.err log-bin = mysql-bin log-bin-index = mysql-bin.index rpl_semi_sync_master_enabled = 1 rpl_semi_sync_master_timeout = 1000 rpl_semi_sync_slave_enabled = 1 relay_log_purge = 0 relay-log = relay-bin relay-log-index = slave-relay-bin.index [client] host = 127.0.0.1 user = root password = 123.com
slave:
[root@slave ~]# cat /etc/my.cnf
[mysqld] basedir = /usr/local/mysql datadir = /usr/local/mysql/data port = 3306 server_id = 3 socket = /usr/local/mysql/mysql.sock log-error=/usr/local/mysql/data/mysqld.err log-bin = mysql-bin log-bin-index = mysql-bin.index rpl_semi_sync_slave_enabled = 1 relay-log = relay-bin relay-log-index = slave-relay-bin.index read_only = 1 [client] host = 127.0.0.1 user = root password = 123.com
全部重启服务
[root@master1 ~]# systemctl restart mysqld
mysql> show variables like "%rpl_semi_sync%";
| Variable_name | Value |
|---|---|
| rpl_semi_sync_master_enabled | ON |
| rpl_semi_sync_master_timeout | 1000 |
| rpl_semi_sync_master_trace_level | 32 |
| rpl_semi_sync_master_wait_for_slave_count | 1 |
| rpl_semi_sync_master_wait_no_slave | ON |
| rpl_semi_sync_master_wait_point | AFTER_SYNC |
| rpl_semi_sync_slave_enabled | ON |
| rpl_semi_sync_slave_trace_level | 32 |
这是主从master的半同步状态
mysql> show variables like "%rpl_semi_sync%";
| Variable_name | Value |
|---|---|
| rpl_semi_sync_master_enabled | OFF |
| rpl_semi_sync_master_timeout | 10000 |
| rpl_semi_sync_master_trace_level | 32 |
| rpl_semi_sync_master_wait_for_slave_count | 1 |
| rpl_semi_sync_master_wait_no_slave | ON |
| rpl_semi_sync_master_wait_point | AFTER_SYNC |
| rpl_semi_sync_slave_enabled | ON |
| rpl_semi_sync_slave_trace_level | 32 |
这是slave的半同步状态，发现主插件是关闭的
④权限与change
master1:
mysql> grant replication slave on *.* to rep@"%" identified by "123.com"; mysql> show master status; +------------------+----------+--------------+------------------+-------------------+ | File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set | +------------------+----------+--------------+------------------+-------------------+ | mysql-bin.000001 | 436 | | | | +------------------+----------+--------------+------------------+-------------------+
master2:
mysql> grant replication slave on *.* to rep@"%" identified by "123.com"; mysql> change master to master_host="192.168.1.12",master_user="rep",master_password="123.com",master_log_file="mysql-bin.000001",master_log_pos=436; mysql> start slave;
slave:
mysql> change master to master_host="192.168.1.12",master_user="rep",master_password="123.com",master_log_file="mysql-bin.000001",master_log_pos=436; mysql> start slave;
回到master1:
mysql> grant all privileges on *.* to manager@"%" identified by "123.com"; mysql> show status like "%rpl_semi_sync%"; +--------------------------------------------+-------+ | Variable_name | Value | +--------------------------------------------+-------+ | Rpl_semi_sync_master_clients | 2 | | Rpl_semi_sync_master_net_avg_wait_time | 0 | +--------------------------------------------+-------+
因为已经配置主从复制，在master1上创建manager用户同步到其他主机授权manager监控节点工作
三、配置MHA步骤：
①安装MHA(manager节点两个包都需要安装，三台DB只需要安装node包)
例如master1:
[root@master1 ~]# tar zxf mha4mysql-node-0.56.tar.gz
[root@master1 ~]# cd mha4mysql-node-0.56/
[root@master1 mha4mysql-node-0.56]# perl Makefile.PL
[root@master1 mha4mysql-node-0.56]# make && make install
manager:
[root@manager ~]# tar zxf mha4mysql-node-0.56.tar.gz
[root@manager ~]# cd mha4mysql-node-0.56/
[root@manager mha4mysql-node-0.56]# perl Makefile.PL
[root@manager mha4mysql-node-0.56]# make && make install
[root@manager mha4mysql-node-0.56]# cd ..
[root@manager ~]# tar zxf mha4mysql-manager-0.56.tar.gz
[root@manager ~]# cd mha4mysql-manager-0.56/
[root@manager mha4mysql-manager-0.56]# perl Makefile.PL
[root@manager mha4mysql-manager-0.56]# make && make install
创建一些可用目录
[root@manager ~]# cd /
[root@manager /]# mkdir etc/masterha
[root@manager /]# mkdir -p masterha/app1
[root@manager /]# mkdir scripts
[root@manager /]# cd ~/mha4mysql-manager-0.56/
[root@manager mha4mysql-manager-0.56]# cp samples/conf/* /etc/masterha/
[root@manager mha4mysql-manager-0.56]# cp samples/scripts/* /scripts/
[root@manager mha4mysql-manager-0.56]#
②配置MHA
[root@manager ~]# vim /etc/masterha/app1.cnf
[server default]
manager_workdir=//masterha/app1
manager_log=/masterha/app1/manager.log
user=manager
password=123.com
ssh_user=root
repl_user=rep
repl_password=123.com
ping_interval=1
[server1]
hostname=192.168.1.12
port=3306
master_binlog_dir=/usr/local/mysql/data
candidate_master=1
[server2]
hostname=192.168.1.13
port=3306
master_binlog_dir=/usr/local/mysql/data
candidate_master=1
[server3]
hostname=192.168.1.14
port=3306
master_binlog_dir=/usr/local/mysql/data
no_master=1
③ssh有效性验证
[root@manager ~]# masterha_check_ssh --global_conf=/etc/masterha/masterha_default.cnf --conf=/etc/masterha/app1.cnf
....... Tue Apr 24 16:46:58 2018 - [debug] ok. Tue Apr 24 16:46:58 2018 - [debug] Connecting via SSH from root@192.168.1.14(192.168.1.14:22) to root@192.168.1.13(192.168.1.13:22).. Tue Apr 24 16:46:58 2018 - [debug] ok. Tue Apr 24 16:46:58 2018 - [info] All SSH connection tests passed successfully.
如有报错，务必检查无密ssh连接情况，确保其他主机已经分享公钥
④集群复制有效性验证
[root@manager ~]# masterha_check_ssh --global_conf=/etc/masterha/masterha_default.cnf --conf=/etc/masterha/app1.cnf
.......... Tue Apr 24 16:50:24 2018 - [info] Connecting to root@192.168.1.13(192.168.1.13:22).. Can"t exec "mysqlbinlog": No such file or directory at /usr/local/share/perl5/MHA/BinlogManager.pm line 106. mysqlbinlog version command failed with rc 1:0, please verify PATH, LD_LIBRARY_PATH, and client options at /usr/local/bin/apply_diff_relay_logs line 492. Tue Apr 24 16:50:25 2018 - [error][/usr/local/share/perl5/MHA/MasterMonitor.pm, ln201] Slaves settings check failed! Tue Apr 24 16:50:25 2018 - [error][/usr/local/share/perl5/MHA/MasterMonitor.pm, ln390] Slave configuration failed. Tue Apr 24 16:50:25 2018 - [error][/usr/local/share/perl5/MHA/MasterMonitor.pm, ln401] Error happend on checking configurations. at /usr/local/bin/masterha_check_repl line 48. Tue Apr 24 16:50:25 2018 - [error][/usr/local/share/perl5/MHA/MasterMonitor.pm, ln500] Error happened on monitoring servers. Tue Apr 24 16:50:25 2018 - [info] Got exit code 1 (Not master dead). MySQL Replication Health is NOT OK!
发现报错Can"t exec "mysqlbinlog": No such file or directory at /usr/local/share/perl5/MHA/BinlogManager.pm line 106.
解决方法在所有DB服务器进行软连接执行文件操作
[root@master1 ~]# ln -s /usr/local/mysql/bin/* /usr/local/bin
⑤启动manager
[root@manager ~]# nohup masterha_manager --conf=/etc/masterha/app1.cnf &> /tmp/mha_manager.log &
[1] 8126
[root@manager ~]# masterha_check_status --conf=/etc/masterha/app1.cnf
app1 (pid:8126) is running(0:PING_OK), master:192.168.1.12四、MHA高可用验证
步骤：
①将master1中mysql服务宕掉
[root@master1 ~]# systemctl stop mysqld
②在manager查看MHA日志
[root@manager ~]# cat /masterha/app1/manager.log
....... Started automated(non-interactive) failover. The latest slave 192.168.1.13(192.168.1.13:3306) has all relay logs for recovery. Selected 192.168.1.13 as a new master. 192.168.1.13: OK: Applying all logs succeeded. 192.168.1.14: This host has the latest relay log events. Generating relay diff files from the latest slave succeeded. 192.168.1.14: OK: Applying all logs succeeded. Slave started, replicating from 192.168.1.13. 192.168.1.13: Resetting slave info succeeded. Master failover to 192.168.1.13(192.168.1.13:3306) completed successfully
发现master failover已经成功
③查看slave复制状态
mysql> show slave statusG
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.1.13
Master_User: rep
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 436
......
发现master IP已经转为192.168.1.13，io线程与sql线程正常运行，MHA搭建成功
④MHA manager端日常操作
1)发生主从切换后，manager服务会自动停掉，却在manager_workdir(/masterha/app1)目录生成文件app1.failover.complate，若要启动MHA，必须确保此文件已经删除
[root@manager ~]# cd /masterha/
[root@manager masterha]# ls
app1
[root@manager masterha]# cd app1/
[root@manager app1]# ls
app1.failover.complete manager.log
[root@manager app1]# mv app1.failover.complete /tmp
2)重新定义master1位置，需要把master1设置为master2的slave服务器
mysql> change master to master_host="192.168.1.13",master_user="rep",master_password="123.com",master_log_file="mysql-bin.000001",master_log_pos=436;
mysql> start slave;
3)停止MHA
[root@manager app1]# masterha_stop --conf=/etc/masterha/app1.cnf
4)启动MHA
[root@manager app1]# nohup masterha_manager --conf=/etc/masterha/app1.cnf &> /tmp/mha_manager.log &
[1] 8613
[root@manager app1]# masterha_check_status --conf=/etc/masterha/app1.cnf
app1 (pid:8613) is running(0:PING_OK), master:192.168.1.13
5)主从切换后续工作
重构计划，切换后的master2成为主库，想要master1重夺主库，重新执行以上五步，包括停止master2库。原主库数据文件完整情况可以通过以下方式得到change master命令
[root@manager app1]# grep -i "change master to master" /masterha/app1/manager.log | tail -1
Tue Apr 24 17:16:59 2018 - [info] All other slaves should start replication from here. Statement should be: CHANGE MASTER TO MASTER_HOST="192.168.1.12", MASTER_PORT=3306, MASTER_LOG_FILE="mysql-bin.000002", MASTER_LOG_POS=154, MASTER_USER="rep", MASTER_PASSWORD="xxx";
mysql> CHANGE MASTER TO MASTER_HOST="192.168.1.12", MASTER_PORT=3306, MASTER_LOG_FILE="mysql-bin.000002", MASTER_LOG_POS=154, MASTER_USER="rep", MASTER_PASSWORD="123.com";
mysql> start slave;
mysql> show slave status G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.1.12
Master_User: rep
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000002
Read_Master_Log_Pos: 154
[root@manager ~]# cd /masterha/app1/
[root@manager app1]# ls
app1.failover.complete manager.log
[root@manager app1]# mv app1.failover.complete /tmp
mv: overwrite ‘/tmp/app1.failover.complete’? y
[root@manager app1]# nohup masterha_manager --conf=/etc/masterha/app1.cnf &> /tmp/mha_manager.log &
[1] 9015
[root@manager app1]# masterha_check_status --conf=/etc/masterha/app1.cnf
app1 (pid:9015) is running(0:PING_OK), master:192.168.1.12
6)定期删除中继日志
在配置主从复制中，slave设置了参数relay_log_purge=0，所以slave节点需要定期删除中继日志，建议每个slave节点删除中继日志时间错开
[root@slave ~]# crontab -e
0 5 * * * /usr/local/bin/purge_relay_logs --user=root --password=123.com --port=3306 --disable_relay_log_purge >> /var/log/purge_ relay.log 2>&五、配置VIP
vip配置可以采用两种方式，一种通过keepalived方式管理虚拟ip浮动；另一种通过脚本启动虚拟ip方式(就是不需要任何第三方应用程序)
1.keepalived方式管理虚拟ip步骤：
①在两台master安装keepalived
[root@master1 ~]# wget http://www.keepalived.org/sof...
[root@master1 ~]# yum -y install openssl openssl-devel
[root@master1 ~]# cd keepalived-1.4.3/
[root@master1 keepalived-1.4.3]# ./configure --prefix=/ && make && make install
[root@master1 keepalived-1.4.3]# whereis keepalived
keepalived: /usr/sbin/keepalived /etc/keepalived
检查cent7启动脚本中执行程序位置
[root@master1 ~]# vim /usr/lib/systemd/system/keepalived.service
[Unit] Description=LVS and VRRP High Availability Monitor After= network-online.target syslog.target Wants=network-online.target [Service] Type=forking PIDFile=/var/run/keepalived.pid KillMode=process EnvironmentFile=-//etc/sysconfig/keepalived ExecStart=/usr/sbin/keepalived $KEEPALIVED_OPTIONS ExecReload=/bin/kill -HUP $MAINPID [Install] WantedBy=multi-user.target
②配置keepalived
master1：
[root@master1 ~]# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
router_id mysql-ha1
}
vrrp_instance VI_1 {
state BACKUP
interface eno16777736
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.1.100
}
}
master2：
[root@master2 ~]# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
router_id mysql-ha2
}
vrrp_instance VI_1 {
state BACKUP
interface eno16777736
virtual_router_id 51
priority 90
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.1.100
}
}
③启动keepalived
[root@master1 ~]# systemctl start keepalived
[root@master2 ~]# systemctl start keepalived
查看master1虚拟ip状态
[root@master1 ~]# ip a
