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Slave_SQL_Running: No mysql同步故障解决方法
Slave_SQL_Running: No mysql同步故障解决
今天检查数据库发现一台MySQL Slave未和主机同步,查看Slave状态:
mysql> show slave status/G
Slave_IO_Running: Yes
Slave_SQL_Running: No
Last_Errno: 1062
....
Seconds_Behind_Master:NULL
原因:
1.程序可能在slave上进行了写操作
2.也可能是slave机器重起后,事务回滚造成的.
解决办法I:
1.首先停掉Slave服务:slave stop
2.到主服务器上查看主机状态:
记录File和Position对应的值。
mysql> show master status;
+------------------+-----------+--------------+------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+-----------+--------------+------------------+
| mysql-bin.000020 | 135617781 | | |
+------------------+-----------+--------------+------------------+
1 row in set (0.00 sec)
3.到slave服务器上执行手动同步:
mysql> change master to
> master_host='master_ip',
> master_user='user',
> master_password='pwd',
> master_port=3307,
> master_log_file='mysql-bin.000020',
> master_log_pos=135617781;
1 row in set (0.00 sec)
mysql> slave start;
1 row in set (0.00 sec)
再次查看slave状态发现:
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
...
Seconds_Behind_Master: 0
解决办法II:
mysql> slave stop;
mysql> set GLOBAL SQL_SLAVE_SKIP_COUNTER=1;
mysql> slave start;
自己的使用体会:方法一是强制性从某一个点开始同步,会有部分没有同步的数据丢失,后续主服务器上删除记录同步也会有一些错误信息,不会影响使用.方法二不一定会有效果.
=======================================================================================]
1,主从不能同步:
show slave status;报错:Error xxx dosn't exist
且show slave status/G:
Slave_SQL_Running: NO
Seconds_Behind_Master: NULL
解决方法:
stop slave;
set global sql_slave_skip_counter =1 ;
start slave;
之后Slave会和Master去同步 主要看:
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Seconds_Behind_Master是否为0,0就是已经同步了
2,还需要做的一些优化与监视:
show full processlist; //查看mysql当前同步线程号
skip-name-resolve //跳过dns名称查询,有助于加快连接及同步的速度
max_connections=1000 //增大Mysql的连接数目,(默认100)
max_connect_errors=100 //增大Mysql的错误连接数目,(默认10)
查看日志一些命令
1, show master status/G;
在这里主要是看log-bin的文件是否相同。
show slave status/G;
在这里主要是看:
Slave_IO_Running=Yes
Slave_SQL_Running=Yes
如果都是Yes,则说明配置成功.
2,在master上输入show processlist/G;
mysql> SHOW PROCESSLIST/G
*************************** 1. row ***************************
Id: 2
User: root
Host: localhost:32931
db: NULL
Command: Binlog Dump
Time: 94
State: Has sent all binlog to slave; waiting for binlog to
be updated
Info: NULL
如果出现Command: Binlog Dump,则说明配置成功.
stop slave #停止同步
start slave #开始同步,从日志终止的位置开始更新。
SET SQL_LOG_BIN=0|1 #主机端运行,需要super权限,用来开停日志,随意开停,会造成主机从机数据不一致,造成错误
SET GLOBAL SQL_SLAVE_SKIP_COUNTER=n # 客户端运行,用来跳过几个事件,只有当同步进程出现错误而停止的时候才可以执行。
RESET MASTER #主机端运行,清除所有的日志,这条命令就是原来的FLUSH MASTER
RESET SLAVE #从机运行,清除日志同步位置标志,并重新生成master.info
虽然重新生成了master.info,但是并不起用,最好,将从机的mysql进程重启一下,
LOAD TABLE tblname FROM MASTER #从机运行,从主机端重读指定的表的数据,每次只能读取一个,受timeout时间限制,需要调整timeout时间。执行这个命令需要同步账号有 reload和super权限。以及对相应的库有select权限。如果表比较大,要增加net_read_timeout 和 net_write_timeout的值
LOAD DATA FROM MASTER #从机执行,从主机端重新读入所有的数据。执行这个命令需要同步账号有reload和super权限。以及对相应的库有select权限。如果表比较大,要增加net_read_timeout 和 net_write_timeout的值
CHANGE MASTER TO master_def_list #在线改变一些主机设置,多个用逗号间隔,比如
CHANGE MASTER TO
MASTER_HOST='master2.mycompany.com',
MASTER_USER='replication',
MASTER_PASSWORD='bigs3cret'
MASTER_POS_WAIT() #从机运行
SHOW MASTER STATUS #主机运行,看日志导出信息
SHOW SLAVE HOSTS #主机运行,看连入的从机的情况。
SHOW SLAVE STATUS (slave)
SHOW MASTER LOGS (master)
SHOW BINLOG EVENTS [ IN 'logname' ] [ FROM pos ] [ LIMIT [offset,] rows ]
PURGE [MASTER] LOGS TO 'logname' ; PURGE [MASTER] LOGS BEFORE 'date'

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