MHA是一套Mysql故障切换方案,来保障数据库的高可用性,它的功能是能在0-30s之内实现主Mysql故障转移(failover),MHA故障转移可以很好的帮我们解决从库数据的一致性问题,同时最大化挽回故障发生后数据的一致性。 操作系统版本:Red Hat Enterprise Linux Server release 6.9 (Santiago) 192.168.1.11 master 192.168.1.12 slave01 192.168.1.13 slave02 192.168.1.14 manager

下面开始安装: 1.准备安装包,FTP到/usr/local/

1.1解压安装包

tar zxvf mysql-5.6.39-linux-glibc2.12-x86_64.tar.gz

重命名

mv mysql-5.6.39-linux-glibc2.12-x86_64 mysql

1.2 安装 辅助软件 yum -y install perl perl-devel

2.添加用户

groupadd mysql

useradd -r -g mysql mysql

3.修改目录权限

chown -R mysql.mysql /usr/local/mysql mkdir -p /data/mysql chown -R mysql.mysql /data/mysql

4.初始化数据库

/usr/local/mysql/scripts/mysql_install_db --user=mysql--basedir=/usr/local/mysql --datadir=/usr/local/mysql/data

5.注册服务

cp /usr/local/mysql//support-files/mysql.server/etc/rc.d/init.d/mysql

cp /usr/local/mysql/support-files/my-default.cnf /etc/my.cnf

chkconfig --add mysql

chkconfig mysql on

6.启动服务

service mysql start

7、ssh无密码登录

#主机:master执行命令

[root@master ~]# ssh-keygen -t rsa [root@master ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@manager [root@master ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@slave01 [root@master ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@slave02 #主机:slave01执行命令

[root@slave01 ~]# ssh-keygen -t rsa [root@slave01 ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@manager [root@slave01 ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@master [root@slave01 ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@slave02 #主机: slave02执行命令

[root@slave02 ~]# ssh-keygen -t rsa [root@slave02 ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@manager [root@slave02 ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@master [root@slave02 ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@slave01 #主机:manager执行命令

[root@manager ~]# ssh-keygen -t rsa [root@manager ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@master [root@manager ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@slave01 [root@manager ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@slave02

8.配置Mysql服务器

#master配置文件/usr/local/mysql/etc/my.cnf 配置如下: basedir = /usr/local//mysql datadir = /data/mysql port = 3306 server_id = 241 socket = /tmp/mysql.sock log-bin=mysql-bin log-slave-updates expire_logs_days = 10 #slave01配置文件/usr/local/mysql/etc/my.cnf 配置如下:

basedir = /usr/local/mysql datadir = /data/mysql port = 3306 server_id = 242 socket = /tmp/mysql.sock log-bin=mysql-bin log-slave-updates expire_logs_days = 10 #slave02配置文件/usr/local/mysql/etc/my.cnf 配置如下:

basedir = /usr/local//mysql datadir = /data/mysql port = 3306 server_id = 243 socket = /tmp/mysql.sock log-bin=mysql-bin log-slave-updates expire_logs_days = 10 read_only = 1

9.配置master、slave01和slave02之间的主从复制 在MySQL5.6 的主从配置中,master端同样要开启两个重要的选项,server-id和log-bin,并且选项server-id在全局架构中并且唯一,不能被其它主机使用,这里采用主机ip地址的最后一位充当server-id的值;slave端要开启relay-log;

#主机: master执行命令

[root@master ~]# egrep "log-bin|server_id" /usr/local/lnmp/mysql/etc/my.cnf server_id = 11 log-bin=mysql-bin #主机: slave01执行命令

[root@slave01 ~]# egrep "log-bin|server_id" /usr/local/lnmp/mysql/etc/my.cnf server_id = 12 log-bin=mysql-bin #主机: slave02执行命令

[root@slave02 ~]# egrep "log-bin|server_id" /usr/local/lnmp/mysql/etc/my.cnf server_id = 13 log-bin=mysql-bin

10.在master、slave01上创建主从同步的账号。slave01是备用master,这个也需要建立授权用户。

[root@master ~]# mysql -uroot -p123456 -e "grant replication slave on . to 'backup'@'192.168.1.%' identified by 'backup';flush privileges;" [root@slave01 ~]# mysql -uroot -p123456 -e "grant replication slave on . to 'backup'@'192.168.1.%' identified by 'backup';flush privileges;"

11.在master上执行命令,查看master状态信息

[root@master ~]# mysql -uroot -p123456 -e 'show master status;' Warning: Using a password on the command line interface can be insecure. +------------------+----------+--------------+------------------+-------------------+ | File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set | +------------------+----------+--------------+------------------+-------------------+ | mysql-bin.000004 | 118 | | | | +------------------+----------+--------------+------------------+-------------------+

12.在slave01和slave02上执行主从同步

#slave01配置主从

[root@slave01 ~]# mysql -uroot -p123456 mysql> change master to -> master_host='192.168.1.11',master_user='backup',master_password='backup',master_port=3306,master_log_file='mysql-bin.000004',master_log_pos=118; Query OK, 0 rows affected, 2 warnings (0.56 sec)

mysql> start slave; Query OK, 0 rows affected (0.05 sec)

mysql> show slave status\G; *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.1.11 Master_User: backup Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000004 Read_Master_Log_Pos: 118 Relay_Log_File: slave01-relay-bin.000002 Relay_Log_Pos: 283 Relay_Master_Log_File: mysql-bin.000004 Slave_IO_Running: Yes Slave_SQL_Running: Yes Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0 Last_Error: Skip_Counter: 0 Exec_Master_Log_Pos: 118 Relay_Log_Space: 458 Until_Condition: None Until_Log_File: Until_Log_Pos: 0 Master_SSL_Allowed: No Master_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: 0 Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 11 Master_UUID: cb4af7bc-d600-11e5-8101-26c537b62ad9 Master_Info_File: /data/mysql/master.info SQL_Delay: 0 SQL_Remaining_Delay: NULL Slave_SQL_Running_State: Slave has read all relay log; waiting for the slave I/O thread to update it Master_Retry_Count: 86400 Master_Bind: Last_IO_Error_Timestamp: Last_SQL_Error_Timestamp: Master_SSL_Crl: Master_SSL_Crlpath: Retrieved_Gtid_Set: Executed_Gtid_Set: Auto_Position: 0 1 row in set (0.00 sec)

#slave02配置主从

[root@slave02 ~]# mysql -uroot -p123456 mysql> change master to -> master_host='192.168.1.11',master_user='backup',master_password='backup',master_port=3306,master_log_file='mysql-bin.000004',master_log_pos=118; Query OK, 0 rows affected, 2 warnings (0.56 sec)

mysql> start slave; Query OK, 0 rows affected (0.05 sec) mysql> show slave status\G; *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.1.11 Master_User: backup Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000004 Read_Master_Log_Pos: 118 Relay_Log_File: slave01-relay-bin.000002 Relay_Log_Pos: 283 Relay_Master_Log_File: mysql-bin.000004 Slave_IO_Running: Yes Slave_SQL_Running: Yes Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0 Last_Error: Skip_Counter: 0 Exec_Master_Log_Pos: 118 Relay_Log_Space: 458 Until_Condition: None Until_Log_File: Until_Log_Pos: 0 Master_SSL_Allowed: No Master_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: 0 Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 11 Master_UUID: cb4af7bc-d600-11e5-8101-26c537b62ad9 Master_Info_File: /data/mysql/master.info SQL_Delay: 0 SQL_Remaining_Delay: NULL Slave_SQL_Running_State: Slave has read all relay log; waiting for the slave I/O thread to update it Master_Retry_Count: 86400 Master_Bind: Last_IO_Error_Timestamp: Last_SQL_Error_Timestamp: Master_SSL_Crl: Master_SSL_Crlpath: Retrieved_Gtid_Set: Executed_Gtid_Set: Auto_Position: 0 1 row in set (0.00 sec)

13.开始MHA的建设 13.1、创建账号,每台数据库(master、slave01、slave02)上都要创建账号,在这里以其中master为例.。

[root@master ~]# mysql -uroot -p123456 -e "grant all privileges on . to 'mha_rep'@'192.168.1.%' identified by '123456';flush privileges;" mysql> select host,user from user; +---------------+---------+ | host | user | +---------------+---------+ | 192.168.1.% | backup | | 192.168.1.% | mha_rep | | localhost | root | +---------------+---------+ 3 rows in set (0.00 sec)

13.2、在3台主机上(master、slave01和slave02)上分别安装mha4mysql-node包,这里以master为例,其它主机同理。

[root@master ~]# yum install perl-DBD-MySQL -y [root@master ~]# rpm -ivh https://downloads.mariadb.com/files/MHA/mha4mysql-node-0.54-0.el6.noarch.rpm

13.3、在manager上安装mha4mysql-manager和mha4mysql-node包

[root@manager ~]# yum install perl cpan perl-DBD-MySQL perl-Config-Tiny perl-Log-Dispatch perl-Parallel-ForkManager perl-Net-Telnet -y [root@manager ~]# rpm -ivh https://downloads.mariadb.com/files/MHA/mha4mysql-node-0.54-0.el6.noarch.rpm [root@manager ~]# wget https://downloads.mariadb.com/files/MHA/mha4mysql-manager-0.56.tar.gz [root@manager ~]# tar zvxf mha4mysql-manager-0.56.tar.gz [root@manager ~]# cd mha4mysql-manager-0.56 [root@manager ~]# perl Makefile.PL [root@manager mha4mysql-manager-0.56]# make && make install [root@manager mha4mysql-manager-0.56]# mkdir -p /usr/local/mha/scripts [root@manager mha4mysql-manager-0.56]# cp samples/conf/app1.cnf /usr/local/mha/mha.cnf [root@manager mha4mysql-manager-0.56]# cp samples/scripts/* /usr/local/mha/scripts/

13.4、修改manager端mha的配置文件,如下

[root@manager ~]# cat /usr/local/mha/mha.cnf [server default] user=mha_rep #MHA管理mysql的用户名 password=123456 #MHA管理mysql的密码 manager_workdir=/usr/local/mha #MHA的工作目录 manager_log=/usr/local/mha/manager.log #MHA的日志路径 ssh_user=root #免秘钥登陆的用户名 repl_user=backup #主从复制账号,用来在主从之间同步数据 repl_password=backup ping_interval=1 #ping间隔时间,用来检查master是否正常

[server1] hostname=192.168.1.11 port=3306 master_binlog_dir=/data/mysql/ candidate_master=1

[server2] hostname=192.168.1.12 port=3306 master_binlog_dir=/data/mysql/ candidate_master=1

[server3] hostname=192.168.1.13 port=3306 master_binlog_dir=/data/mysql/ no_master=1

13.5、检查ssh是否畅通 [root@manager mha4mysql-manager-0.56]# masterha_check_ssh --conf=/usr/local/mha/mha.cnf Can't locate Params/Validate.pm in @INC (@INC contains: /usr/local/lib64/perl5 /usr/local/share/perl5 /usr/lib64/perl5/vendor_perl /usr/share/perl5/vendor_perl /usr/lib64/perl5 /usr/share/perl5 .) at /usr/share/perl5/vendor_perl/Log/Dispatch.pm line 9. BEGIN failed--compilation aborted at /usr/share/perl5/vendor_perl/Log/Dispatch.pm line 9. Compilation failed in require at /usr/local/share/perl5/MHA/SSHCheck.pm line 29. BEGIN failed--compilation aborted at /usr/local/share/perl5/MHA/SSHCheck.pm line 29. Compilation failed in require at /usr/local/bin/masterha_check_ssh line 25. BEGIN failed--compilation aborted at /usr/local/bin/masterha_check_ssh line 25.

通过安装包解决此问题 [root@manager mha4mysql-manager-0.56]# yum install perl-Params-Validate Loaded plugins: product-id, refresh-packagekit, search-disabled-repos, security, subscription-manager This system is not registered with an entitlement server. You can use subscription-manager to register. Setting up Install Process Resolving Dependencies --> Running transaction check ---> Package perl-Params-Validate.x86_64 0:0.92-3.el6 will be installed --> Finished Dependency Resolution

Dependencies Resolved

======================================================================================================================================================================= Package Arch Version Repository Size

Installing: perl-Params-Validate x86_64 0.92-3.el6 Server 75 k

Transaction Summary

Install 1 Package(s)

Total download size: 75 k Installed size: 175 k Is this ok [y/N]: y Downloading Packages: Running rpm_check_debug Running Transaction Test Transaction Test Succeeded Running Transaction Warning: RPMDB altered outside of yum. ** Found 5 pre-existing rpmdb problem(s), 'yum check' output follows: perl-Log-Dispatch-2.27-1.el6.noarch has missing requires of perl(MIME::Lite) perl-Log-Dispatch-2.27-1.el6.noarch has missing requires of perl(Mail::Send) perl-Log-Dispatch-2.27-1.el6.noarch has missing requires of perl(Mail::Sender) perl-Log-Dispatch-2.27-1.el6.noarch has missing requires of perl(Mail::Sendmail) perl-Log-Dispatch-2.27-1.el6.noarch has missing requires of perl(Params::Validate) Installing : perl-Params-Validate-0.92-3.el6.x86_64 1/1 Verifying : perl-Params-Validate-0.92-3.el6.x86_64 1/1

Installed: perl-Params-Validate.x86_64 0:0.92-3.el6

Complete!

[root@manager ~]# masterha_check_ssh --conf=/usr/local/mha/mha.cnf Thu May 17 18:42:22 2018 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping. Thu May 17 18:42:22 2018 - [info] Reading application default configurations from /usr/local/mha/mha.cnf.. Thu May 17 18:42:22 2018 - [info] Reading server configurations from /usr/local/mha/mha.cnf.. Thu May 17 18:42:22 2018 - [info] Starting SSH connection tests.. Thu May 17 18:42:25 2018 - [debug] Thu May 17 18:42:22 2018 - [debug] Connecting via SSH from root@192.168.1.11(192.168.1.11:22) to root@192.168.1.12(192.168.1.12:22).. Thu May 17 18:42:24 2018 - [debug] ok. Thu May 17 18:42:24 2018 - [debug] Connecting via SSH from root@192.168.1.11(192.168.1.11:22) to root@192.168.1.13(192.168.1.13:22).. Thu May 17 18:42:25 2018 - [debug] ok. Thu May 17 18:42:26 2018 - [debug] Thu May 17 18:42:23 2018 - [debug] Connecting via SSH from root@192.168.1.12(192.168.1.12:22) to root@192.168.1.11(192.168.1.11:22).. Thu May 17 18:42:24 2018 - [debug] ok. Thu May 17 18:42:24 2018 - [debug] Connecting via SSH from root@192.168.1.12(192.168.1.12:22) to root@192.168.1.13(192.168.1.13:22).. Thu May 17 18:42:26 2018 - [debug] ok. Thu May 17 18:42:26 2018 - [debug] Thu May 17 18:42:23 2018 - [debug] Connecting via SSH from root@192.168.1.13(192.168.1.13:22) to root@192.168.1.11(192.168.1.11:22).. Thu May 17 18:42:25 2018 - [debug] ok. Thu May 17 18:42:25 2018 - [debug] Connecting via SSH from root@192.168.1.13(192.168.1.13:22) to root@192.168.1.12(192.168.1.12:22).. Thu May 17 18:42:26 2018 - [debug] ok. Thu May 17 18:42:26 2018 - [info] All SSH connection tests passed successfully.

13.6、masterha_check_repl工具检查mysql主从复制是否成功 [root@manager mha]# masterha_check_repl --conf=/usr/local/mha/mha.cnf Tue May 15 09:46:42 2018 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping. Tue May 15 09:46:42 2018 - [info] Reading application default configurations from /usr/local/mha/mha.cnf.. Tue May 15 09:46:42 2018 - [info] Reading server configurations from /usr/local/mha/mha.cnf.. Tue May 15 09:46:42 2018 - [info] MHA::MasterMonitor version 0.56. Tue May 15 09:46:42 2018 - [info] Dead Servers: Tue May 15 09:46:42 2018 - [info] Alive Servers: Tue May 15 09:46:42 2018 - [info] 192.168.1.11(192.168.1.11:3306) Tue May 15 09:46:42 2018 - [info] 192.168.1.12(192.168.1.12:3306) Tue May 15 09:46:42 2018 - [info] 192.168.1.13(192.168.1.13:3306) Tue May 15 09:46:42 2018 - [info] Alive Slaves: Tue May 15 09:46:42 2018 - [info] 192.168.1.12(192.168.1.12:3306) Version=5.6.39-log (oldest major version between slaves) log-bin:enabled Tue May 15 09:46:42 2018 - [info] Replicating from 192.168.1.11(192.168.1.11:3306) Tue May 15 09:46:42 2018 - [info] Primary candidate for the new Master (candidate_master is set) Tue May 15 09:46:42 2018 - [info] 192.168.1.13(192.168.1.13:3306) Version=5.6.39-log (oldest major version between slaves) log-bin:enabled Tue May 15 09:46:42 2018 - [info] Replicating from 192.168.1.11(192.168.1.11:3306) Tue May 15 09:46:42 2018 - [info] Not candidate for the new Master (no_master is set) Tue May 15 09:46:42 2018 - [info] Current Alive Master: 192.168.1.11(192.168.1.11:3306) Tue May 15 09:46:42 2018 - [info] Checking slave configurations.. Tue May 15 09:46:42 2018 - [info] read_only=1 is not set on slave 192.168.1.12(192.168.1.12:3306). Tue May 15 09:46:42 2018 - [warning] relay_log_purge=0 is not set on slave 192.168.1.12(192.168.1.12:3306). Tue May 15 09:46:42 2018 - [warning] relay_log_purge=0 is not set on slave 192.168.1.13(192.168.1.13:3306). Tue May 15 09:46:42 2018 - [info] Checking replication filtering settings.. Tue May 15 09:46:42 2018 - [info] binlog_do_db= , binlog_ignore_db= Tue May 15 09:46:42 2018 - [info] Replication filtering check ok. Tue May 15 09:46:42 2018 - [info] Starting SSH connection tests.. Tue May 15 09:46:46 2018 - [info] All SSH connection tests passed successfully. Tue May 15 09:46:46 2018 - [info] Checking MHA Node version.. Tue May 15 09:46:47 2018 - [info] Version check ok. Tue May 15 09:46:47 2018 - [info] Checking SSH publickey authentication settings on the current master.. Tue May 15 09:46:48 2018 - [info] HealthCheck: SSH to 192.168.1.11 is reachable. Tue May 15 09:46:49 2018 - [info] Master MHA Node version is 0.54. Tue May 15 09:46:49 2018 - [info] Checking recovery script configurations on the current master.. Tue May 15 09:46:49 2018 - [info] Executing command: save_binary_logs --command=test --start_pos=4 --binlog_dir=/data/mysql/ --output_file=/var/tmp/save_binary_logs_test --manager_version=0.56 --start_file=mysql-bin.000004 Tue May 15 09:46:49 2018 - [info] Connecting to root@192.168.1.11(192.168.1.11).. Creating /var/tmp if not exists.. ok. Checking output directory is accessible or not.. ok. Binlog found at /data/mysql/, up to mysql-bin.000004 Tue May 15 09:46:49 2018 - [info] Master setting check done. Tue May 15 09:46:49 2018 - [info] Checking SSH publickey authentication and checking recovery script configurations on all alive slave servers.. Tue May 15 09:46:49 2018 - [info] Executing command : apply_diff_relay_logs --command=test --slave_user='mha_rep' --slave_host=192.168.1.12 --slave_ip=192.168.1.12 --slave_port=3306 --workdir=/var/tmp --target_version=5.6.39-log --manager_version=0.56 --relay_log_info=/data/mysql/relay-log.info --relay_dir=/data/mysql/ --slave_pass=xxx Tue May 15 09:46:49 2018 - [info] Connecting to root@192.168.1.12(192.168.1.12:22).. Checking slave recovery environment settings.. Opening /data/mysql/relay-log.info ... ok. Relay log found at /data/mysql, up to slave01-relay-bin.000002 Temporary relay log file is /data/mysql/slave01-relay-bin.000002 Testing mysql connection and privileges..Warning: Using a password on the command line interface can be insecure. ERROR 1045 (28000): Access denied for user 'mha_rep'@'slave01' (using password: YES) mysql command failed with rc 1:0! at /usr/bin/apply_diff_relay_logs line 367 main::check() called at /usr/bin/apply_diff_relay_logs line 486 eval {...} called at /usr/bin/apply_diff_relay_logs line 466 main::main() called at /usr/bin/apply_diff_relay_logs line 112 Tue May 15 09:46:50 2018 - [error][/usr/local/share/perl5/MHA/MasterMonitor.pm, ln201] Slaves settings check failed! Tue May 15 09:46:50 2018 - [error][/usr/local/share/perl5/MHA/MasterMonitor.pm, ln390] Slave configuration failed. Tue May 15 09:46:50 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 May 15 09:46:50 2018 - [error][/usr/local/share/perl5/MHA/MasterMonitor.pm, ln500] Error happened on monitoring servers. Tue May 15 09:46:50 2018 - [info] Got exit code 1 (Not master dead).

MySQL Replication Health is NOT OK!

解决方法: [root@master bin]# mysql -uroot -p Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 56 Server version: 5.6.39-log MySQL Community Server (GPL)

Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> use mysql Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A

Database changed mysql> select user,host from user; +---------+-------------+ | user | host | +---------+-------------+ | root | 127.0.0.1 | | backup | 192.168.1.% | | mha_rep | 192.168.1.% | | root | ::1 | | | localhost | | mha_rep | localhost | | root | localhost | | | master | | root | master | +---------+-------------+ 9 rows in set (0.03 sec)

mysql> grant all privileges on . to mha_rep@'192.168.1.12' identified by '123456'; Query OK, 0 rows affected (0.00 sec)

mysql> grant all privileges on . to mha_rep@'192.168.1.13' identified by '123456'; Query OK, 0 rows affected (0.02 sec)

mysql> grant all privileges on . to mha_rep@'192.168.1.11' identified by '123456'; Query OK, 0 rows affected (0.00 sec)

mysql>

再次运行监测脚本masterha_check_repl --conf=/usr/local/mha/mha.cnf后报错; Can't exec "mysqlbinlog": No such file or directory at /usr/local/share/perl5/MHA/BinlogManager.pm line 99. mysqlbinlog version not found!

缺少软连接,我们在三个库中都创建一下软连接; ln -s /usr/local/mysql/bin/mysql /usr/bin/mysql ln -s /usr/local/mysql/bin/mysqlbinlog /usr/local/bin/mysqlbinlog 再次检测通过;

14.mha实验模拟

1、在每次做mha实验的时候,我们都最好先执行如下命令做检测

[root@manager ~]# masterha_check_ssh --conf=/usr/local/mha/mha.cnf [root@manager ~]# masterha_check_repl --conf=/usr/local/mha/mha.cnf #确定两条命令的返回结果都是无异常的,然后启动mha服务

2、在manager端启动mha服务并时刻监控日志文件的输出变化

[root@manager ~]# nohup masterha_manager --conf=/usr/local/mha/mha.cnf > /tmp/mha_manager.log 2>&1 & [root@manager ~]# ps -ef |grep masterha |grep -v 'grep'

3、测试master宕机后,时候会自动切换 #测试前查看slave01,slave02的主从同步情况 #slave01

[root@slave01 ~]# mysql -uroot -p123456 -e 'show slave status\G' |egrep 'Slave_IO_Running:|Slave_SQL_Running:' Warning: Using a password on the command line interface can be insecure. Slave_IO_Running: Yes Slave_SQL_Running: Yes #slave02

[root@slave02 ~]# mysql -uroot -p123456 -e 'show slave status\G' |egrep 'Slave_IO_Running:|Slave_SQL_Running:' Warning: Using a password on the command line interface can be insecure. Slave_IO_Running: Yes Slave_SQL_Running: Yes

#停止master的mysql服务

[root@master ~]# service mysql stop Shutting down MySQL..... [ OK ]

#我们查看slave02的主从同步信息

[root@slave02 ~]# mysql -uroot -p123456 -e 'show slave status\G' |egrep 'Master_Host|Slave_IO_Running:|Slave_SQL_Running:' Warning: Using a password on the command line interface can be insecure. Master_Host: 192.168.1.12 #表明已经转移新的ip Slave_IO_Running: Yes #主从正常 Slave_SQL_Running: Yes 4、恢复master服务 #删除故障转移文件

[root@manager mha]# rm -rf /usr/local/mha/mha.failover.complete #重启mysql服务

[root@master ~]# service mysqld start

#在manager的日子文件中找到主从同步的sql语句

[root@manager mha]# grep MASTER_HOST /usr/local/mha/manager.log Tue May 15 10:08:54 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.000001', MASTER_LOG_POS=2294, MASTER_USER='backup', MASTER_PASSWORD='xxx'; #在master上启动主从同步,密码为backup

mysql> change master to -> master_host='192.168.1.12'',master_user='backup',master_password='backup',master_port=3306,master_log_file='mysql-bin.000001',master_log_pos=2294; Query OK, 0 rows affected, 2 warnings (0.75 sec)

mysql> start slave; Query OK, 0 rows affected (0.05 sec) #在master和slave02上执行,检查主从同步是否都正常,这里以master为例,slave02同理

[root@master ~]# mysql -uroot -p123456 -e 'show slave status\G' |egrep 'Master_Host|Slave_IO_Running:|Slave_SQL_Running:' Warning: Using a password on the command line interface can be insecure. Master_Host: 192.168.1.12 Slave_IO_Running: Yes Slave_SQL_Running: Yes 5、再次启动MHA的manager服务,并停止slave01

[root@manager ~]# nohup masterha_manager --conf=/usr/local/mha/mha.cnf > /tmp/mha_manager.log 2>&1 & #关闭slave01的mysql服务

[root@slave01 ~]# service mysqld stop Shutting down MySQL... SUCCESS [root@manager mha]# tail -f /usr/local/mha/manager.log

#在slave02上查看主从同步情况

[root@slave02 ~]# mysql -uroot -p123456 -e 'show slave status\G' |egrep 'Master_Host|Slave_IO_Running:|Slave_SQL_Running:' Warning: Using a password on the command line interface can be insecure. Master_Host: 192.168.1.12 Slave_IO_Running: Yes Slave_SQL_Running: Yes 6、恢复slave01服务 #删除故障转移文件

[root@manager mha]# rm -rf /usr/local/mha/mha.failover.complete #重启mysql服务

[root@slave01 ~]# service mysqld start Starting MySQL ... SUCCESS! #在manager的日子文件中找到主从同步的sql语句

[root@manager mha]# grep MASTER_HOST /usr/local/mha/manager.log Tue May 15 10:25:51 2018 - [info] All other slaves should start replication from here. Statement should be: CHANGE MASTER TO MASTER_HOST='192.168.1.11', MASTER_PORT=3306, MASTER_LOG_FILE='mysql-bin.000005', MASTER_LOG_POS=120, MASTER_USER='backup', MASTER_PASSWORD='xxx'; #在slave01上启动主从同步,密码为backup

mysql> change master to -> master_host='192.168.1.11',master_user='backup',master_password='backup',master_port=3306,master_log_file='mysql-bin.000005',master_log_pos=120; Query OK, 0 rows affected, 2 warnings (0.61 sec)

mysql> start slave; Query OK, 0 rows affected (0.05 sec) #在slave01和slave02上执行,检查主从同步是否都正常,这里以slave01为例,slave02同理。

[root@slave01 ~]# mysql -uroot -p123456 -e 'show slave status\G' |egrep 'Master_Host|Slave_IO_Running:|Slave_SQL_Running:' Warning: Using a password on the command line interface can be insecure. Master_Host: 192.168.1.11 Slave_IO_Running: Yes Slave_SQL_Running: Yes 7、再次启动MHA的manager服务

[root@manager ~]# nohup masterha_manager --conf=/usr/local/mha/mha.cnf > /tmp/mha_manager.log 2>&1 &

15.通过vip实现mysql的高可用 1、修改/usr/local/mha/mha.cnf

[root@manager mha]# more cat /usr/local/mha/mha.cnf cat: No such file or directory :::::::::::::: /usr/local/mha/mha.cnf ::::::::::::::

[server default] user=mha_rep password=123456 manager_workdir=/usr/local/mha manager_log=/usr/local/mha/manager.log master_ip_failover_script=/usr/local/mha/scripts/master_ip_failover #定制perl脚本 ssh_user=root repl_user=backup repl_password=backup ping_interval=1

[server1] hostname=192.168.1.11 port=3306 master_binlog_dir=/data/mysql/ candidate_master=1

[server2] hostname=192.168.1.12 port=3306 master_binlog_dir=/data/mysql/ candidate_master=1

[server3] hostname=192.168.1.13 port=3306 master_binlog_dir=/data/mysql/ no_master=1

2、修改脚本/usr/local/mha/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 = '192.168.1.240'; my $key = '1'; my $ssh_start_vip = "/sbin/ifconfig eth0:$key $vip"; my $ssh_stop_vip = "/sbin/ifconfig eth0:$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" ) {

    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" ) {

    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";
    exit 0;
}
else {
    &usage();
    exit 1;
}

} 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"; }

3、模拟故障进行切换

#停止master的mysql服务

[root@master ~]# service mysqld stop Shutting down MySQL... SUCCESS! #查看slave02的同步信息

[root@slave02 ~]# mysql -uroot -p123456 -e 'show slave status\G' |egrep 'Master_Host|Slave_IO_Running:|Slave_SQL_Running:' Warning: Using a password on the command line interface can be insecure. Master_Host: 192.168.1.12 Slave_IO_Running: Yes Slave_SQL_Running: Yes #查看slave01的IP信息

eth0 Link encap:Ethernet HWaddr 00:0C:29:EB:86:1F
inet addr:192.168.1.12 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::20c:29ff:feeb:861f/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:59533 errors:0 dropped:0 overruns:0 frame:0 TX packets:27157 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:63732835 (60.7 MiB) TX bytes:4660626 (4.4 MiB)

eth0:1 Link encap:Ethernet HWaddr 00:0C:29:01:46:B7
inet addr:192.168.1.240 Bcast:192.168.1.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 4、恢复master服务与上面恢复方法一样。

PS:配置文件中请勿添加注释,要不然会有意想不到的问题,如: mha.cnf 配置文件中,我们上面添加了#定制perl脚本,就会在启动MHA时候报错,ps -ef 查看mha进程,发现不在。查看日志文件如下报错;

tail: /tmp/mha_manager.log: nohup: ignoring input Thu May 17 15:14:46 2018 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping. Thu May 17 15:14:46 2018 - [info] Reading application default configurations from /usr/local/mha/mha.cnf.. Thu May 17 15:14:46 2018 - [info] Reading server configurations from /usr/local/mha/mha.cnf..

Use of uninitialized value $command in string eq at /usr/local/mha/scripts/master_ip_failover line 29.

16.日常维护命令

1.检查状态

masterha_check_status --conf=/usr/local/mha/mha.cnf 2.停止 masterha_stop masterha_check_status --conf=/usr/local/mha/mha.cnf