扬州西区网站建设,园林绿化东莞网站建设,成都网站排名生客seo怎么样,杭州优化公司在线留言MySQL主从介绍MySQL主从叫做Replication、AB复制#xff0c;A和B做主从后#xff0c;在A上写数据。B上也会同步A的数据#xff0c;两者实现实时同步MySQL是基于binlog日志来同步的#xff0c;主上必须开启binlog才能进行主从同步#xff0c;同步过程大概有三个步骤(1)主将…MySQL主从介绍MySQL主从叫做Replication、AB复制A和B做主从后在A上写数据。B上也会同步A的数据两者实现实时同步MySQL是基于binlog日志来同步的主上必须开启binlog才能进行主从同步同步过程大概有三个步骤(1)主将数据操作更改的记录到binlog中(2)主从之间同步比较binlog的事件记录A将事件记录到binlog里从同步到本地后也会在本机上记录一个relaylog的文件(3)从根据relaylog里面的事件记录来执行同步主上有一个log dump的线程用来和从的I/O线程传递binlog从上会有两个线程其中I/O线程用于同步binlog的记录并产生relaylog记录另一个SQL线程用来执行relaylog中的事务把SQL数据在主上按大小、改变、来一一同步主从同步有两种场景模式主-从主负责所有的数据查询和更改从只负责数据的备份只起到备份的作用主写-从读主负责数据来源的存储和修改不用于数据查询。从不仅起到实时备份的作用还对外部提供查询数据的访问这样可以减小主数据库的访问压力主从数据库准备安装mysql数据库可以参考另一篇文章对mysql的编译安装参数参考[rootlocalhost mysql-5.7.22]# cmake . -DCMALE_INSTALL_PREFIX/usr/local/mysql -DMYSQL_DATADIR/var/mysql/data -DSYSCONFDIR/etc -DWITH_MYISAM_STORAGE_ENGINE1 -DWITH_INNOBASE_STORAGE_ENGINE1 -DWITH_ARCHIVE_STORAGE_ENGINE1 -DMYSQL_UNIX_ADDR/usr/local/mysql/mysql.sock -DWITH_PARTITION_STORAGE_ENGINE1 -DEXTRA_CHARSETSall -DDEFAULT_CHARSETutf8 -DDEFAULT_COLLATIONutf8_general_ci -DWITH-SYSTEMD1 -DWITH_BOOST/usr/local/boost-----------------------省略过程------------------------ CMAKE_C_LINK_FLAGS:-- CMAKE_CXX_LINK_FLAGS:-- CMAKE_C_FLAGS_RELWITHDEBINFO: -O3 -g -fabi-version2 -fno-omit-frame-pointer -fno-strict-aliasing -DDBUG_OFF-- CMAKE_CXX_FLAGS_RELWITHDEBINFO: -O3 -g -fabi-version2 -fno-omit-frame-pointer -fno-strict-aliasing -DDBUG_OFF-- Configuring done-- Generating done-- Build files have been written to: /usr/local/src/mysql-5.7.22[rootlocalhost mysql-5.7.22]# echo $?0结果无报错继续make编译[rootlocalhost mysql-5.7.22]# makeScanning dependencies of target abi_check[ 0%] Built target abi_checkScanning dependencies of target INFO_SRC[ 0%] Built target INFO_SRCScanning dependencies of target INFO_BIN[ 0%] Built target INFO_BINScanning dependencies of target zlib----------------省略过程------------------------[ 99%] Building C object libmysqld/examples/CMakeFiles/mysql_client_test_embedded.dir/__/__/testclients/mysql_client_test.c.o[ 99%] Linking CXX executable mysql_client_test_embedded[ 99%] Built target mysql_client_test_embeddedScanning dependencies of target my_safe_process[100%] Building CXX object mysql-test/lib/My/SafeProcess/CMakeFiles/my_safe_process.dir/safe_process.cc.o[100%] Linking CXX executable my_safe_process[100%] Built target my_safe_process[rootlocalhost mysql-5.7.22]# aecho $?0安装无报错完成最后安装make install-----------------------过程省略----------------------- Installing: /usr/local/mysql/support-files/mysqld_multi.server-- Installing: /usr/local/mysql/support-files/mysql-log-rotate-- Installing: /usr/local/mysql/support-files/magic-- Installing: /usr/local/mysql/share/aclocal/mysql.m4-- Installing: /usr/local/mysql/support-files/mysql.server[rootlocalhost mysql-5.7.22]# echo $?0基本的安装完成接下来就是配置mysql的启动和配置项递归指定mysql所属用户和所属组的权限[rootlocalhost ]# chown -R mysql:mysql /usr/local/mysql/数据库的初始化编译好的数据库进行初始化其中mysql初始化信息中包含一个随机生成的密码[rootlocalhost mysql-5.7.22]# /usr/local/mysql/bin/mysqld --initialize --usermysql --basedir/usr/local/mysql --datadir/usr/local/mysql/data2018-07-28T09:08:42.088874Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).2018-07-28T09:08:42.590615Z 0 [Warning] InnoDB: New log files created, LSN457902018-07-28T09:08:42.861362Z 0 [Warning] InnoDB: Creating foreign key constraint system tables.2018-07-28T09:08:42.955937Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: d342a57c-9245-11e8-bf5e-080027a7f9c2.2018-07-28T09:08:42.965634Z 0 [Warning] Gtid table is not ready to be used. Table mysql.gtid_executed cannot be opened.2018-07-28T09:08:42.966858Z 1 [Note] A temporary password is generated for rootlocalhost: tHuQg%M!12jmy.cnf和/etc/init.d/mysqld文件拷贝服务启动文件并修改my.cnf配置文件。指定mysql安装路径和存储数据的路径及添加系统服务[rootlocalhost ]# cp /usr/local/src/mysql-5.7.22/support-files/mysql.server /etc/init.d/mysqld[rootlocalhost ]# vim /etc/init.d/mysqld~basedir/usr/local/mysql/datadir/usr/local/mysql/data/~[rootlocalhost ]# chmod x /etc/init.d/mysqld[rootlocalhost ]# ls -l /etc/init.d/mysqld-rwxr-xr-x 1 root root 10609 7月 28 17:21 /etc/init.d/mysqld[rootlocalhost ]# chkconfig --add mysqld[rootlocalhost ]# chkconfig --list注意该输出结果只显示 SysV 服务并不包含原生 systemd 服务。SysV 配置数据可能被原生 systemd 配置覆盖。如果您想列出 systemd 服务,请执行 systemctl list-unit-files。欲查看对特定 target 启用的服务请执行systemctl list-dependencies [target]。mysqld 0:关 1:关 2:开 3:开 4:开 5:开 6:关netconsole 0:关 1:关 2:关 3:关 4:关 5:关 6:关network 0:关 1:关 2:开 3:开 4:开 5:开 6:关编辑my.cnf的mysql配置文件log-error是记录启动时报错的错误信息。在报错pid的错误中有尝试把basedir 的配置给注释掉然后mysql能正常启动了查看错误日志记录日志记录报错unknown variable /usr/local/mysql/ 未知的变量路径说明my.cnf指定的路径有问题这里我直接注释掉basedir这个路径然后启动成功[rootlocalhost ]# less /etc/my.cnf[mysqld]basedir /usr/local/mysql/datadir /usr/local/mysql/dataport 3306character-set-server utf8explicit_defaults_for_timestamp true# socket /var/run/mysqld/mysqld.sock# Disabling symbolic-links is recommended to prevent assorted security riskssymbolic-links0# Settings user and group are ignored when systemd is used.# If you need to run mysqld under a different user or group,# customize your systemd unit file for mariadb according to the# instructions in http://fedoraproject.org/wiki/Systemd[mysqld_safe]log-error/var/log/mariadb/mariadb.logpid-file/var/run/mariadb/mariadb.pidlog-error /data/mysql/logs/error.log## include all files from the config directory#!includedir /etc/my.cnf.dmysql的启动过程添加完成跟随系统启动后启动mysql服务[rootlocalhost ]# /etc/init.d/mysqld startStarting MySQL.2018-07-28T09:23:23.822700Z mysqld_safe error: log-error set to /var/log/mariadb/mariadb.log, however file dont exists. Create writable for user mysql.ERROR! The server quit without updating PID file (/usr/local/mysql/data/localhost.pid).根据报错提示创建了mysql的日志文件然后再尝试启动[rootlocalhost ]# mkdir -p /var/log/mariadb/mariadb[rootlocalhost ]# touch /var/log/mariadb/mariadb.log[rootlocalhost ]# chown -R mysql:mysql /var/log/mariadb/mariadb再次尝试启动mysql服务并启动成功[rootlocalhost support-files]# /etc/init.d/mysqld startStarting MySQL. SUCCESS![rootlocalhost support-files]# ps -aux |grep mysqlroot 21812 0.0 0.1 113312 1636 pts/0 S 17:28 0:00 /bin/sh /usr/local/mysql//bin/mysqld_safe --datadir/usr/local/mysq/data --pid-file/usr/local/mysql/data/localhost.pidmysql 22000 1.7 16.3 1112372 166604 pts/0 Sl 17:28 0:00 /usr/local/mysql/bin/mysqld --basedir/usr/local/mysql/ --datadir/usr/local/mysql/data --plugin-dir/usr/local/mysql//lib/plugin --usermysql --log-error/var/log/mariadb/mariadb.log --pid-file/usr/local/mysql/data/localhost.pid --port3306root 22030 0.0 0.0 112724 976 pts/0 R 17:28 0:00 grep --colorauto mysql将mysql命令写入系统文件中这样就能在命令行中直接使用mysql这个命令了[rootlocalhost mysql]# echo export PATH$PATH:/usr/local/mysql/bin/ /etc/profile[rootlocalhost mysql]# source /etc/profile[rootlocalhost mysql]# echo /usr/local/mysql/lib/ /etc/ld.so.conf[rootlocalhost mysql]# ldconfig建立master和slave的主从通信步骤一master主配置清除iptables防火墙规则由于没有清除iptables。导致进来的数据被转发重定向到其他IP地址上了[rootaaa ~]# iptables -nvLChain INPUT (policy ACCEPT 0 packets, 0 bytes)pkts bytes target prot opt in out source destination4811 348K ACCEPT all -- * * 0.0.0.0/0 0.0.0.0/0 state RELATED,ESTABLISHED1 84 ACCEPT icmp -- * * 0.0.0.0/0 0.0.0.0/04 324 ACCEPT all -- lo * 0.0.0.0/0 0.0.0.0/02 104 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:2213467 1028K REJECT all -- * * 0.0.0.0/0 0.0.0.0/0 reject-with icmp-host-prohibitedChain FORWARD (policy ACCEPT 0 packets, 0 bytes)pkts bytes target prot opt in out source destination0 0 REJECT all -- * * 0.0.0.0/0 0.0.0.0/0 reject-with icmp-host-prohibitedChain OUTPUT (policy ACCEPT 3311 packets, 1476K bytes)pkts bytes target prot opt in out source destination[rootaaa ~]# iptables -F安装完mysql后对my.cnf配置文件进行修改添加binlog日志的记录指定主从运行时的serverID。修改my.cnf添加binlog日志的产生配置并指定mysql的运行server级别ID如果只同步或不同步的库就需要在my.cnf中指定不同步或同步的库#binlog-do-dbdb1 #只针对指定库同步#binlog-ignore-dbmysql 针对某些库不同步[rootaaa /]# vim /etc/my.cnf[mysqld]basedir /usr/local/mysql/datadir /usr/local/mysql/dataport 3306character-set-server utf8explicit_defaults_for_timestamp trueserver-id 10log-bin zidingyi在数据库中创建一个从数据库使用访问的授权用户用于从在master中读取数据并进行同步的作用mysql grant replication slave on *.* to repl192.168.1.220 identified by xiangchen ;Query OK, 0 rows affected, 1 warning (0.00 sec)查看主数据库中的binlog存储的值这个是用于记录数据存储大小的记录的如果数据表发生读写变化这里也会发生改变。在主从同步前需要在主库锁表停止数据库读写。file是指定生成binlog文件的名称Position是数据存储的变化值通过这个值来进行同步这个值也表达了binlog文件的改变大小mysql show master status;------------------------------------------------------------------------------| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |------------------------------------------------------------------------------| zidingyi.000001 | 1108 | | | |------------------------------------------------------------------------------1 row in set (0.00 sec)将主库锁表暂时禁止读取写入mysql flush tables with read lock;Query OK, 0 rows affected (0.01 sec)步骤二slave从配置slave角色上同样需要清除iptables规则以免主从之间无法通信slave从上配置my.cnf修改server-id这个id不能小于主上的配置数值越小优先级越高。从服务器的my.cnf不需要配置log-bin因为是slave的角色所以只需要从master那里同步数据即可[rootHuaching-2 ~]# vim /etc/my.cnf[mysqld]#bashdir /usr/local/mysql/datadir /data/mysqlport 3306character-set-server utf8explicit_defaults_for_timestamp trueserver-id 20重启后登入从数据库中先暂停slave的角色并在数据库中写入与master通信的一些信息(binlog记录的数值)。master_log_file是指定主上生成binlog文件的名称slave会通过这个名称去找对应的binlog文件。master_log_pos是指定master数据存储的变化值通过这个值来进行同步这个值也表达了binlog文件的改变大小[rootHuaching-2 ~]# /etc/init.d/mysqld restartShutting down MySQL.. SUCCESS!Starting MySQL.. SUCCESS!mysql stop slave ;Query OK, 0 rows affected (0.01 sec)mysql change master to master_host192.168.1.234, master_port3306, master_userslave, master_passwordxiangchen, master_log_filezidingyi.000001, master_log_pos1108;Query OK, 0 rows affected, 2 warnings (0.02 sec)步骤三解除master表锁和启动slave角色进行数据同步设置好master和slave的授权和访问账户设置后解除master的表锁和启动slave的角色并把master中的库拷贝到slave中这样才能够保证启动同步时两边数据的一致性在解除master的表锁之前拷贝master数据到slave中忽略明文密码的警告[rootaaa ~]# mysqldump -uroot -ppwd123 mysql2 my2.dbmysqldump: [Warning] Using a password on the command line interface can be insecure.[rootaaa ~]# mysqldump -uroot -ppwd123 zrlog zrlog.dbmysqldump: [Warning] Using a password on the command line interface can be insecure.将以db结尾的后缀备份文件通过scp、rzsz或者ftp等方法传输到slave上slave在库中需要创建需要恢复库的一个空库用于数据导入mysql create database mysql2;Query OK, 0 rows affected (0.02 sec)mysql create database zrlog;Query OK, 0 rows affected (0.02 sec)mysql exitBye[rootHuaching-2 ~]# mysql -uroot -ppwd123 mysql2 my2.db[rootHuaching-2 ~]# mysql -uroot -ppwd123 zrlog zrlog.dbmaster上可以把数据表锁解除掉让主数据库可以正常读写访问mysql unlock tables;mysql flush privileges;在从数据库启用slave的角色并与master数据库进行数据同步(数据同步前两个数据库数据必须一致否则同步会造成数据不一样的情况发生)mysql start slave;Query OK, 0 rows affected (0.00 sec)查看主从同步的信息这里主要关注 Slave_IO_Running: Yes和 Slave_SQL_Running: Yes这两个值一个表示是否和master正常通信的状态Slave_IO是和master的IO进程通信的一个线程yes表示在正常运行。另一个是表示SQL执行是否在监听状态mysql show slave status\G;*************************** 1. row ***************************Slave_IO_State: Waiting for master to send eventMaster_Host: 192.168.1.234Master_User: slaveMaster_Port: 3306Connect_Retry: 60Master_Log_File: zidingyi.000001Read_Master_Log_Pos: 1108Relay_Log_File: Huaching-2-relay-bin.000002Relay_Log_Pos: 319Relay_Master_Log_File: zidingyi.000001Slave_IO_Running: YesSlave_SQL_Running: YesReplicate_Do_DB:Replicate_Ignore_DB:Replicate_Do_Table:Replicate_Ignore_Table:Replicate_Wild_Do_Table:Replicate_Wild_Ignore_Table:Last_Errno: 0Last_Error:Skip_Counter: 0Exec_Master_Log_Pos: 1108Relay_Log_Space: 531Until_Condition: NoneUntil_Log_File:Until_Log_Pos: 0Master_SSL_Allowed: NoMaster_SSL_CA_File:Master_SSL_CA_Path:Master_SSL_Cert:Master_SSL_Cipher:Master_SSL_Key:Seconds_Behind_Master: 0Master_SSL_Verify_Server_Cert: NoLast_IO_Errno: 0Last_IO_Error:Last_SQL_Errno: 0Last_SQL_Error:Replicate_Ignore_Server_Ids:Master_Server_Id: 10Master_UUID: 9174f3d7-9c9a-11e8-88a9-08002733eddaMaster_Info_File: /data/mysql/master.infoSQL_Delay: 0SQL_Remaining_Delay: NULLSlave_SQL_Running_State: Slave has read all relay log; waiting for more updatesMaster_Retry_Count: 86400Master_Bind:Last_IO_Error_Timestamp:Last_SQL_Error_Timestamp:Master_SSL_Crl:Master_SSL_Crlpath:Retrieved_Gtid_Set:Executed_Gtid_Set:Auto_Position: 0Replicate_Rewrite_DB:Channel_Name:Master_TLS_Version:测试主从同步master和slave的my.cnf中使用的同步配置master的my.cnf中可以指定同步时排除或者只同步某些库#binlog-do-dbdb1 #只针对指定库同步#binlog-ignore-dbmysql 针对某些库不同步slave角色配置针对某些库完全记录执行不会忽略掉binlog中某条SQL执行语句replicate_wild_do_table 支持通配符统配库如user.replicate_wild_ignore_table 表示这个配置里的内容会被忽略执行不建议使用以下的配置参数因为匹配同步的库也有可能会被忽略不去执行匹配库replicate_do_dbreplicate_ignore_db匹配表replicate_do_tablereplicate_ignore_table在主上查询库的操作查询主从数据是否一致相同的库、相同的表mysql use mysql2Database changedmysql select count(*) from user;----------| count(*) |----------| 6 |----------1 row in set (0.00 sec)slave从上的查询结果mysql use mysql2Database changedmysql select count(*) from user;----------| count(*) |----------| 6 |----------1 row in set (0.00 sec)在主上清空这个数据表的内容并查看数据表的行数mysql truncate table user;Query OK, 0 rows affected (0.00 sec)mysql select count(*) from user;----------| count(*) |----------| 0 |----------1 row in set (0.00 sec)slave从上只执行查询数据表行数的操作结果是会把同样的数据执行同步过来mysql select count(*) from user;----------| count(*) |----------| 0 |----------1 row in set (0.00 sec)如果发生在从上删除表删除库的操作此时master主上如果误执行了slave上被删除的内容的话还会造成主从同步发生问题只能通过重新在slave上指定position的值来进行同步了。这种误操作会破坏主从之间的同步从删除某些内容后再次同步时发生的报错信息Last_ SQL_ Error: Error Cant drop database user; database doesnt exist on query. Default database: user. Query: drop database user
