Mysql互为主从问题--日志同步数据不同步_MySQL

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我搭建的是mysql 互为主从 复制

两台机器的mysql环境完全相同

 

第一部分测试：

B为master  A为slave的同步测试

在B上创建表lian，并插入数据
mysql> create table lian (a int,b char(10));

mysql> insert into lian (a,b)values(22,'hahah');

mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| lian           |
+----------------+
mysql> select * from lian;
+------+-------+
| a    | b     |
+------+-------+
|   22 | hahah |
+------+-------+

查看一下master-B的binlog日志，查看以上操作是否记录了日志：
cat mysql-bin.000002                                                                                                                                                                                  
.?Nh?@stdtestcreate table lian (a int,b char(10))??Nl>@stdtestinsert into lian (a,b)values(22,'hahah')

现在查看slave-A的relay日志，发现日志已经同步了
[root@XKWB5510 var]# cat XKWB5510-relay-bin.000003                                                                                                                                                     
.?Nh?@stdtestcreate table lian (a int,b char(10))??Nl>@stdtestinsert into lian (a,b)values(22,'hahah')

再在slave-A上看一下数据库是不是存在lian这个表：
mysql> use test;
Database changed
mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| aniya          |
| lian           |
+----------------+
2 rows in set (0.00 sec)

 

现在说明数据B A 主 从 同步成功
---------------------------------------------------------------------------
第二部分测试：

A为master  B为slave的同步测试

 

在A上创建表From246，并插入数据
mysql> use test;
mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| A246           |
| aniya          |
| lian           |
+----------------+
3 rows in set (0.00 sec)

mysql> create table From246(Name varchar(255),Sex varchar(255),Age int(10));
mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| A246           |
| From246        |
| aniya          |
| lian           |
+----------------+
4 rows in set (0.00 sec)

mysql> insert into From246 (Name,Sex,Age)values('Zhaoyj','Girl',24);
mysql> select * from From246;
+--------+------+------+
| Name   | Sex  | Age  |
+--------+------+------+
| Zhaoyj | Girl |   24 |
+--------+------+------+
1 row in set (0.00 sec)

查看master-A的binlog日志,证明上述操作成功
[root@XKWB5510 var]# tail -1  mysql-bin.000002
testcreate table From246(Name varchar(255),Sex varchar(255),Age int(10))?N?R@stdtestinsert into From246 (Name,Sex,Age)values('Zhaoyj','Girl',24)

查看master-A的日志状态
[root@XKWB5510 var]# /usr/local/mysql/bin/mysqlbinlog mysql-bin.000003 |tail -15
/*!*/;
# at 702
#110926 14:01:51 server id 1  end_log_pos 838  Query thread_id=5 exec_time=0 error_code=0
SET TIMESTAMP=1317016911/*!*/;
create table From246(Name varchar(255),Sex varchar(255),Age int(10))
/*!*/;
# at 838
#110926 14:02:05 server id 1  end_log_pos 966  Query thread_id=5 exec_time=0 error_code=0
SET TIMESTAMP=1317016925/*!*/;
insert into From246 (Name,Sex,Age)values('Zhaoyj','Girl',24)
/*!*/;
DELIMITER ;
# End of log file
ROLLBACK /* added by mysqlbinlog */;
/*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/;

查看relay-B的日志，同步日志成功
testcreate table From246(Name varchar(255),Sex varchar(255),Age int(10))?N?R@stdtestinsert into From246 (Name,Sex,Age)values('Zhaoyj','Girl',24)[root@XKWB5705 var]

查看relay-B日志状态，可以看到日志已经同步
[root@XKWB5705 var]# /usr/local/mysql/bin/mysqlbinlog XKWB5705-relay-bin.000005|tail -13
/usr/local/mysql/bin/mysqlbinlog: Character set '#28' is not a compiled character set and is not specified in the '/usr/local/mysql/share/mysql/charsets/Index.xml' file
#110926 14:01:51 server id 1  end_log_pos 838  Query thread_id=5 exec_time=0 error_code=0
SET TIMESTAMP=1317016911/*!*/;
create table From246(Name varchar(255),Sex varchar(255),Age int(10))
/*!*/;
# at 853
#110926 14:02:05 server id 1  end_log_pos 966  Query thread_id=5 exec_time=0 error_code=0
SET TIMESTAMP=1317016925/*!*/;
insert into From246 (Name,Sex,Age)values('Zhaoyj','Girl',24)
/*!*/;
DELIMITER ;
# End of log file
ROLLBACK /* added by mysqlbinlog */;
/*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/;

但是数据却没有插入到relay-B的数据库
mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| lian           |
+----------------+
1 row in set (0.00 sec)

当我删除master-A上的表时，relay-B日志也同步了
[root@XKWB5705 var]# tail -4 XKWB5705-relay-bin.000005                                                                                                                                                  
??NS?@stdtestdrop table A246??NT@stdtestdrop table aniya??NSd@stdtestdrop table lian??NV?@stdtestdrop table From246

 

这是什么奇怪问题 ？？
------------------------------------------------------------------------------
问题排查：

首先在Master-A上用

show processlist; 查看下进程是否Sleep太多。发现很正常

show master status; 也正常

再跑到Slave上查看 show slave status; 也正常

当我手动从A导入B数据时，发现一个问题：
mysql> load table From246 from master;
ERROR 1115 (42000): Unknown character set: 'gbk'

怀疑：难道是因为字符串的问题导致AB主从复制失败 ？

通过show character set 命令查看到
master-A有gbk字符集而slave-B没有
mysql> show character set;
+----------+-----------------------------+---------------------+--------+
| Charset  | Description                 | Default collation   | Maxlen |
+----------+-----------------------------+---------------------+--------+
| dec8     | DEC West European           | dec8_swedish_ci     |      1 |
| cp850    | DOS West European           | cp850_general_ci    |      1 |
| hp8      | HP West European            | hp8_english_ci      |      1 |
| koi8r    | KOI8-R Relcom Russian       | koi8r_general_ci    |      1 |
| latin1   | cp1252 West European        | latin1_swedish_ci   |      1 |
| latin2   | ISO 8859-2 Central European | latin2_general_ci   |      1 |
| swe7     | 7bit Swedish                | swe7_swedish_ci     |      1 |
| ascii    | US ASCII                    | ascii_general_ci    |      1 |
| hebrew   | ISO 8859-8 Hebrew           | hebrew_general_ci   |      1 |
| koi8u    | KOI8-U Ukrainian            | koi8u_general_ci    |      1 |
| greek    | ISO 8859-7 Greek            | greek_general_ci    |      1 |
| cp1250   | Windows Central European    | cp1250_general_ci   |      1 |
| gbk      | GBK Simplified Chinese      | gbk_chinese_ci      |      2 |
| latin5   | ISO 8859-9 Turkish          | latin5_turkish_ci   |      1 |
| armscii8 | ARMSCII-8 Armenian          | armscii8_general_ci |      1 |
| utf8     | UTF-8 Unicode               | utf8_general_ci     |      3 |
| cp866    | DOS Russian                 | cp866_general_ci    |      1 |
| keybcs2  | DOS Kamenicky Czech-Slovak  | keybcs2_general_ci  |      1 |
| macce    | Mac Central European        | macce_general_ci    |      1 |
| macroman | Mac West European           | macroman_general_ci |      1 |
| cp852    | DOS Central European        | cp852_general_ci    |      1 |
| latin7   | ISO 8859-13 Baltic          | latin7_general_ci   |      1 |
| cp1251   | Windows Cyrillic            | cp1251_general_ci   |      1 |
| cp1256   | Windows Arabic              | cp1256_general_ci   |      1 |
| cp1257   | Windows Baltic              | cp1257_general_ci   |      1 |
| binary   | Binary pseudo charset       | binary              |      1 |
| geostd8  | GEOSTD8 Georgian            | geostd8_general_ci  |      1 |
+----------+-----------------------------+---------------------+--------+
27 rows in set (0.00 sec)

那现在应该是在启动mysql的时候统一他们的字符集
master-A : [root@XKWB5510 var]# /usr/local/mysql/bin/mysqld_safe --default-character-set=latin1 &
slave-B   : [root@XKWB5705 var]# /usr/local/mysql/bin/mysqld_safe --default-character-set=latin1 &

再次在B上从A导入数据：
mysql> show tables;
Empty set (0.00 sec)

mysql> load table From246 from master;
Query OK, 0 rows affected (0.01 sec)

mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| From246        |
+----------------+
1 row in set (0.00 sec)

现在字符集的问题解决了

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

现在手动启动一下“将日志应用于数据库”的线程：SLAVE start SQL_THREAD
和“把master段的日志写到本地”的线程：SLAVE start IO_THREAD

发现同步数据还是失败，那说明不是线程的问题

如果发现 Seconds_Behind_Master 为 (null)
解决：
stop slave;
set global sql_slave_skip_counter =1 ;
start slave;
之后Slave会和Master去同步 主要看Seconds_Behind_Master是否为0，直到为0时就已经同步了。。

 

-----------------------------------
slave B机器上master.info信息，与master A上的信息是否是同步的

mater A：
mysql> show master status/G;
*************************** 1. row ***************************
            File: mysql-bin.000004
        Position: 808
    Binlog_Do_DB: test
Binlog_Ignore_DB: mysql
1 row in set (0.00 sec)

slave B：
[root@XKWB5705 var]# cat master.info
15
mysql-bin.000004
808
211.100.97.246
repl2
123456
3306
60
0

从以上可以看到是同步的

作者“ANLJF的专栏”
 

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