mysql主从复制及mycat读写分离

登录#.#.190.163的服务器，在服务器上配置：
vim /etc/my.cnf
[mysqld]

在此添加如下配置，其中163为服务器的ip最后一位

server_id=163

需要复制的数据库名称

binlog-do-db=xxxy
log-bin=xxxy-bin
binlog_cache_size=1M
binlog_format=mixed
expire_logs_days=100
slave_skip_errors=1062

[root@iZ112fail84Z ~]# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 38
Server version: 5.6.21-log MySQL Community Server (GPL)

Copyright (c) 2000, 2014, 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> grant replication slave,replication client on *.* to 'root'@'120.77.##.##' identified by '123456';
Query OK, 0 rows affected (0.00 sec)

在主数据库上模拟准备需要复制的表；

mysql> create database testpre;
Query OK, 1 row affected (0.00 sec)

mysql> use testpre;
Database changed
mysql> create table pre (id int,name varchar(20));
Query OK, 0 rows affected (0.03 sec)

mysql> insert into pre values (1,'a');
Query OK, 1 row affected (0.00 sec)

mysql> insert into pre values (2,'b');
Query OK, 1 row affected (0.00 sec)

mysql> select * from pre;
+------+------+
| id   | name |
+------+------+
|    1 | a    |
|    2 | b    |
+------+------+
2 rows in set (0.00 sec)

为了保证master和slave的数据一致，采用主库备份，从库还原来实现初始数据一致。
先暂时把要复制的表锁定
主数据库上

mysql> insert into pre values (3,'c');
Query OK, 1 row affected (0.01 sec)

mysql> select * from pre;
+------+------+
| id   | name |
+------+------+
|    1 | a    |
|    2 | b    |
|    3 | c    |
+------+------+
3 rows in set (0.00 sec)

mysql> flush tables with read lock;
Query OK, 0 rows affected (0.01 sec)

mysql> insert into pre values (4,'d');
ERROR 1223 (HY000): Can't execute the query because you have a conflicting read lock

进行数据的导出操作

mysql> exit;
Bye
[root@iZ112fail84Z ~]# mysqldump -uroot -p --add-drop-table testpre >/bak/testpre.sql;
Enter password: 
[root@iZ112fail84Z bak]# cd /bak/
[root@iZ112fail84Z bak]# ls
bakmysql  bakmysqlold  shell  testpre.sql
[root@iZ112fail84Z bak]# pwd

拷贝主库的的testpre.sql文件到从数据库服务器

修改从slave的mysql配置文件/etc/my.cnf
vim /etc/my.cnf
在[mysqld]中增加

设置server_id,一般设置为ip的最后位

server_id=220

复制过滤：需要备份的数据库

binlog-do-db=xxxy

不需要备份的数据库，一般这2种中只设置一种

binlog-ignore-db=mysql

开启二进制日志，以备slave作为其它slave的master时使用

log-bin=xxxy-slave-bin

为每个session分配内存，

binlog_cache_size=1M
binlog_format=mixed
expire_logs_days=100
slave_skip_errors=1062

relay_log配置中继日志

relay_log=xxxy-relay-bin

log_slave_updates 表示slave将复制事件写进自己的二进制日志

log_slave_updates=1

防止从节点的数据改变

read_only=1

service mysql restart

导入主库上的那个脚本到从库

mysqldump -uroot -p testpre < /bak/testpre.sql
或者使用navicat进行数据传输，保证主库和从库中的testpre库中的数据一致

在从库中执行

[root@izwz95v28cpic4beuk0rk0z ~]# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 110
Server version: 5.6.21-log MySQL Community Server (GPL)

Copyright (c) 2000, 2014, 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> change master to master_host='#.#.190.163',master_user='root',master_password='123456',master_port=3306,master_log_file='xxxy-bin.000001',master_log_pos=30042,master_connect_retry=30;
Query OK, 0 rows affected, 2 warnings (0.03 sec)

mysql> 

其中master_log_file和master_log_pos的值分别为在主库上的如下：

mysql> show master status;
+-----------------+----------+--------------+------------------+-------------------+
| File            | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+-----------------+----------+--------------+------------------+-------------------+
| xxxy-bin.000001 |    30042 | xxxy         |                  |                   |
+-----------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

在从服务器上执行：

mysql> show slave status G;
*************************** 1. row ***************************
               Slave_IO_State: 
                  Master_Host: #.#.190.163
                  Master_User: root
                  Master_Port: 3306
                Connect_Retry: 30
              Master_Log_File: xxxy-bin.000001
          Read_Master_Log_Pos: 30042
               Relay_Log_File: xxxy-relay-bin.000001
                Relay_Log_Pos: 4
        Relay_Master_Log_File: xxxy-bin.000001
             Slave_IO_Running: No
            Slave_SQL_Running: No
              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: 30042
              Relay_Log_Space: 120
              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: NULL
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: 0
                  Master_UUID: 
             Master_Info_File: /var/lib/mysql/master.info
                    SQL_Delay: 0
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State: 
           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)

ERROR: 
No query specified
```来查询从的状态
开启主从复制：




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mysql> start slave;
Query OK, 0 rows affected (0.00 sec)

mysql> show slave status G;
***************** 1. row *****************
Slave_IO_State: Waiting for master to send event
Master_Host: #.#.190.163
Master_User: root
Master_Port: 3306
Connect_Retry: 30
Master_Log_File: xxxy-bin.000001
Read_Master_Log_Pos: 30042
Relay_Log_File: xxxy-relay-bin.000002
Relay_Log_Pos: 282
Relay_Master_Log_File: xxxy-bin.000001
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: 30042
Relay_Log_Space: 454
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: 163
Master_UUID: ee963db0-323b-11e7-9fc2-00163e060905
Master_Info_File: /var/lib/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)

ERROR:
No query specified

mysql>

如上：
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
            这2个表示主从同步正常，
查询线程状态：
在master上查看slave的i/o线程创建的连接





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mysql> show processlist G;
***************** 1. row *****************
Id: 8
User: root
Host: #.#.190.163:38009
db: xxxy
Command: Sleep
Time: 1159
State:
Info: NULL

    测试主从复制是否成功：
    之主库中的任意一个表中插入数据后，去从库查看，发现能同步成功了。

测试过程中，如果同步出错，可以在slave上重置主从复制的设置





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mysql>reset slave;
mysql>change master to master_host=’#.#.190.163’,master_user=’root’,master_password=’123456’,master_port=3306,master_log_file=’xxxy-bin.000001’,master_log_pos=30042,master_connect_retry=30;

-------------------------------




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##mycat主从读写分离
www.mycat.org.cn
mycat的读写分离是基于后端mysql集群的主从同步来实现。mycat的提供语句的分发功能。




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[root@iZ112fail84Z ~]# useradd mycat
[root@iZ112fail84Z ~]# passwd mycat
Changing password for user mycat.
New password:
passwd: all authentication tokens updated successfully.
[root@iZ112fail84Z ~]# su mycat
[mycat@iZ112fail84Z root]whoamimycat[mycat@iZ112fail84Zroot] clear
[mycat@iZ112fail84Z root]cd [mycat@iZ112fail84Z ] pwd
/home/mycat
[mycat@iZ112fail84Z ~]$ su root
Password:
[root@iZ112fail84Z mycat]# vim /etc/profile

mycat env

export MYCAT_HOME=/usr/local/mycat
export PATH=PATH:MYCAT_HOME/bin
“/etc/profile” 86L, 2060C written
[root@iZ112fail84Z mycat]# source /etc/profile
[root@iZ112fail84Z mycat]# exit
exit
[mycat@iZ112fail84Z ~]whoamimycat[mycat@iZ112fail84Z ] pwd
/home/mycat
wget http://dl.mycat.io/1.6-RELEASE/Mycat-server-1.6-RELEASE-20161028204710-linux.tar.gz
–2017-10-16 22:18:42– http://dl.mycat.io/1.6-RELEASE/Mycat-server-1.6-RELEASE-20161028204710-linux.tar.gz
Resolving dl.mycat.io… 210.51.26.184
Connecting to dl.mycat.io|210.51.26.184|:80… connected.
HTTP request sent, awaiting response… 200 OK
Length: 15662280 (15M) [application/octet-stream]
Saving to: “Mycat-server-1.6-RELEASE-20161028204710-linux.tar.gz”

100%[============================================================>] 15,662,280 504K/s in 30s

2017-10-16 22:19:13 (502 KB/s) - “Mycat-server-1.6-RELEASE-20161028204710-linux.tar.gz” saved [15662280/15662280]
tar -zxvf Mycat-server-1.6-RELEASE-20161028204710-linux.tar.gz
$ ls
mycat Mycat-server-1.6-RELEASE-20161028204710-linux.tar.gz
su root
Password:
[root@iZ112fail84Z mycat]# ls
mycat Mycat-server-1.6-RELEASE-20161028204710-linux.tar.gz
[root@iZ112fail84Z mycat]# mv /home/mycat/mycat /usr/local/
[root@iZ112fail84Z mycat]# cd /usr/local/mycat/
[root@iZ112fail84Z mycat]# ls
bin catlet conf lib logs version.txt
[root@iZ112fail84Z mycat]# ll
total 24
drwxrwxr-x 2 mycat mycat 4096 Oct 16 22:21 bin
drwxrwxr-x 2 mycat mycat 4096 Mar 1 2016 catlet
drwxrwxr-x 4 mycat mycat 4096 Oct 16 22:21 conf
drwxrwxr-x 2 mycat mycat 4096 Oct 16 22:21 lib
drwxrwxr-x 2 mycat mycat 4096 Oct 28 2016 logs
-rwxrwxr-x 1 mycat mycat 217 Oct 28 2016 version.txt

mycat的配置说明：
如果主从复制需要复制自定义函数及存储过程，需要在/etc/my.cnf的[mysqld]中添加log_bin_trust_function_creates=true

默认linux版的mysql的大小写不敏感，需要在/etc/my.cnf的[mysqld]中添加lower_case_table_names=1

配置mycat的
[root@iZ112fail84Z conf]# pwd
/usr/local/mycat/conf
mycat的核心配置文件：
schema.xml 用于设置mycat的逻辑库，表，数据节点，datahost等内容
conf目录下主要以下三个需要熟悉。

server.xml是Mycat服务器参数调整和用户授权的配置文件

schema.xml是逻辑库定义和表以及分片定义的配置文件

rule.xml是分片规则的配置文件

 vim server.xml 





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1

启动mycat失败,查看日志
[root@iZ112fail84Z bin]# ./mycat start
Starting Mycat-server...
[root@iZ112fail84Z bin]# tail -200 ../logs/wrapper.log 




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INFO | jvm 1 | 2017/11/01 19:27:35 | 2017-11-01 19:27:35,781 [ERROR][WrapperSimpleAppMain] 2017-11-01 19:27:35 startup error java.lang.NumberFormatException: Size must be specified as bytes (b), kibibytes (k), mebibytes (m), gibibytes (g), tebibytes (t), or pebibytes(p). E.g. 50b, 100k, or 250m.
INFO | jvm 1 | 2017/11/01 19:27:35 | Failed to parse byte string: -44040192B

vim server.xml添加如下:





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0

 详见:[错误处理 ](http://blog.csdn.net/gaojingsong/article/details/53244239)

在启动时还是启动不了,查看日志:
tail -200 ../logs/wrapper.log 
提示内存不足





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vim /usr/local/mycat/conf/wrapper.conf
wrapper.java.additional.5=-XX:MaxDirectMemorySize=2G
wrapper.java.additional.10=-Xmx4G
wrapper.java.additional.11=-Xms1G
改为：
wrapper.java.additional.5=-XX:MaxDirectMemorySize=100M
wrapper.java.additional.10=-Xmx100M
wrapper.java.additional.11=-Xms100M

其中的2个配置文件内容:





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2017-11-02 22:21:16.356 DEBUG [$_NIOREACTOR-0-RW] (io.mycat.server.NonBlockingSession.releaseConnection(NonBlockingSession.java:341)) - release connection MySQLConnection [id=20, lastTime=1509632476341, user=root, schema=xxxy, old shema=xxxy, borrowed=true, fromSlaveDB=false, threadId=10487, charset=utf8, txIsolation=3, autocommit=true, attachment=rc_dn2{insert into cash (userid) values (345)}, respHandler=SingleNodeHandler [node=rc_dn2{insert into cash (userid) values (345)}, packetId=1], host=#.#.190.163, port=3306, statusSync=null, writeQueue=0, modifiedSQLExecuted=true]

注意看：host=#.#.190.163 ，
在进行select，发现查询在另一个ip上

配置mycat状态检查服务

在mycat的服务主机上添加mycat服务的状态监测脚本，并开放相应的监测端口，以提供给HAProxy对mycat的服务状态进行检测判断。可以使用xinetd来实现，通过xinetd，HAProxy可以用httpchk来检测mycat的存活状态。

xinetd:网络守护进程服务程序

[root@izwz95v28cpic4beuk0rk0z etc]# yum install xinetd
[root@izwz95v28cpic4beuk0rk0z etc]# cat /etc/xinetd.conf