管理mycat命令详解

mycat监听两个端口，分别为8066和9066；mycat服务默认的数据端口是8066，而9066端口则是mycat管理端口，用于管理mycat的整个集群状态。监听的端口可以在server.xml配置文件中修改。

连接管理端口的方法和连接8066端口的方法基本一样。

[root@test1 conf]# mysql -uroot -P9066 -h127.0.0.1  -p123456            #大写的P指定管理端口
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 19
Server version: 5.6.29-mycat-1.6-RELEASE-20161028204710 MyCat Server (monitor)

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> show @@help;               #查看使用的命令

下面来介绍管理端口中使用的命令：

• reload命令：　　
  • 重新加载配置文件，在修改完配置文件之后，不用重启mycat，可以使用如下命令重新加载：

    mysql> reload @@config;
    Query OK, 1 row affected (0.08 sec)
    Reload config success

  • 从mycat1.5开始新增开启和关闭sql监控分析的指令，需要在QPS测试时关闭SQL监控分析功能，否则测试结果会很差。

    开启SQL监控分析功能：    reload @@sqlstat=open.
    关闭SQL监控分析功能：    reload @@sqlstat=close.
    设置慢SQL时间阈值：      reload @@sqlslow=
    重置SQL监控分析的数据：  reload @@user_stat　：这个命令用于清除缓存。改命令工作在9066端口，用来将客户端执行
                                   show @@sql; show @@sql.sum;show@@slow.success;命令之后的缓存信息清除、　

• show命令：
  • 显示mycat数据库列表，显示列表对应schema.xml配置文件中的schema子节点。

    mysql> show @@database;
    +----------+
    | DATABASE |
    +----------+
    | TESTDB   |
    +----------+
    1 row in set (0.02 sec)

  • 显示mycat数据节点列表，显示列表对应schema.xml配置文件中的dataNode节点。

    mysql> show @@dataNode;
    +------+---------------------+-------+-------+--------+------+------+---------+------------+----------+---------+---------------+
    | NAME | DATHOST             | INDEX | TYPE  | ACTIVE | IDLE | SIZE | EXECUTE | TOTAL_TIME | MAX_TIME | MAX_SQL | RECOVERY_TIME |
    +------+---------------------+-------+-------+--------+------+------+---------+------------+----------+---------+---------------+
    | dn1  | backup-one/mytest   |     0 | mysql |      0 |   10 | 1000 |    5675 |          0 |        0 |       0 |            -1 |
    | dn2  | backup-two/mytest   |     0 | mysql |      0 |   10 | 1000 |    5669 |          0 |        0 |       0 |            -1 |
    | dn3  | backup-three/mytest |     0 | mysql |      0 |   10 | 1000 |    5672 |          0 |        0 |       0 |            -1 |
    +------+---------------------+-------+-------+--------+------+------+---------+------------+----------+---------+---------------+
    3 rows in set (0.01 sec)
    
    #NAME：表示dataNode的名称。
    #DATAHOST：表示对应的datahost属性的值，即数据主机。
    #ACTIVE:表示活跃的连接数量，IDLE：表示空闲的连接数量。SIZE：表示对应的总连接数量。
    
    这个命令可以和where子句结合，查找对应schema的节点数量。
    因为这里只有一个schema，因此显示的结果一样的。
    mysql> show @@dataNode where schema=TESTDB;
    +------+---------------------+-------+-------+--------+------+------+---------+------------+----------+---------+---------------+
    | NAME | DATHOST             | INDEX | TYPE  | ACTIVE | IDLE | SIZE | EXECUTE | TOTAL_TIME | MAX_TIME | MAX_SQL | RECOVERY_TIME |
    +------+---------------------+-------+-------+--------+------+------+---------+------------+----------+---------+---------------+
    | dn1  | backup-one/mytest   |     0 | mysql |      0 |   10 | 1000 |    5703 |          0 |        0 |       0 |            -1 |
    | dn2  | backup-two/mytest   |     0 | mysql |      0 |   10 | 1000 |    5697 |          0 |        0 |       0 |            -1 |
    | dn3  | backup-three/mytest |     0 | mysql |      0 |   10 | 1000 |    5700 |          0 |        0 |       0 |            -1 |
    +------+---------------------+-------+-------+--------+------+------+---------+------------+----------+---------+---------------+
    3 rows in set (0.00 sec)

  • 检查心跳状态。

    mysql> show @@heartbeat;
    +--------+-------+--------------+------+---------+-------+--------+---------+--------------+---------------------+-------+
    | NAME   | TYPE  | HOST         | PORT | RS_CODE | RETRY | STATUS | TIMEOUT | EXECUTE_TIME | LAST_ACTIVE_TIME    | STOP  |
    +--------+-------+--------------+------+---------+-------+--------+---------+--------------+---------------------+-------+
    | hostS3 | mysql | 10.0.102.204 | 3306 |       1 |     0 | idle   |       0 | 2,1,1        | 2019-01-18 22:51:16 | false |
    | hostS2 | mysql | 10.0.102.221 | 3306 |       1 |     0 | idle   |       0 | 1,1,1        | 2019-01-18 22:51:16 | false |
    | hostS1 | mysql | 10.0.102.222 | 3306 |       1 |     0 | idle   |       0 | 1,1,1        | 2019-01-18 22:51:16 | false |
    +--------+-------+--------------+------+---------+-------+--------+---------+--------------+---------------------+-------+
    3 rows in set (0.01 sec)
    
    RS_CODE状态如下：
        OK_STATUS=1代表正常状态。
        ERROR_STATUS =-1 代表连接错误
        TIMEOUT_STATUS=-2代表连接超时
        INIT_STATUS=0代表初始化状态
    若节点发生故障，则会连续进行默认的5个周期检测，心跳连接失败后就会变成-1，节点故障确认，然后可能发生切换。

  • 显示mycat的版本号

    mysql> show @@version;
    +-----------------------------------------+
    | VERSION                                 |
    +-----------------------------------------+
    | 5.6.29-mycat-1.6-RELEASE-20161028204710 |
    +-----------------------------------------+
    1 row in set (0.01 sec)
    
    mysql> 

  • 该命令用于获取mycat当前连接状态，即应用于mycat的连接。

    mysql> show @@connection;
    +------------+------+--------------+------+------------+------+--------+---------+--------+---------+---------------+-------------+------------+---------+------------+
    | PROCESSOR  | ID   | HOST         | PORT | LOCAL_PORT | USER | SCHEMA | CHARSET | NET_IN | NET_OUT | ALIVE_TIME(S) | RECV_BUFFER | SEND_QUEUE | txlevel | autocommit |
    +------------+------+--------------+------+------------+------+--------+---------+--------+---------+---------------+-------------+------------+---------+------------+
    | Processor2 |   20 | 127.0.0.1    | 9066 |      53951 | root | NULL   | utf8:33 |    305 |    3169 |           897 |        4096 |          0 |         |            |
    | Processor3 |   21 | 10.0.102.204 | 8066 |      31165 | root | NULL   | utf8:33 |     99 |     198 |             3 |        4096 |          0 | 3       | true       |
    +------------+------+--------------+------+------------+------+--------+---------+--------+---------+---------------+-------------+------------+---------+------------+
    2 rows in set (0.00 sec)
    
    mysql> 

  • 用于强制关闭连接，id值可由show @@connection命令查看。

    mysql> kill @@connection 21;
    Query OK, 0 rows affected (0.01 sec)

  • 查看后端连接状态：

    mysql> show @@backend;
    +------------+------+---------+--------------+------+--------+--------+---------+-------+--------+----------+------------+--------+----------+---------+------------+
    | processor  | id   | mysqlId | host         | port | l_port | net_in | net_out | life  | closed | borrowed | SEND_QUEUE | schema | charset  | txlevel | autocommit |
    +------------+------+---------+--------------+------+--------+--------+---------+-------+--------+----------+------------+--------+----------+---------+------------+
    | Processor0 |   12 |     121 | 10.0.102.221 | 3306 |  23186 |  45568 |   10848 | 59005 | false  | false    |          0 | mytest | utf8:33  | 3       | true       |
    | Processor0 |   20 |     126 | 10.0.102.221 | 3306 |  23195 |  45668 |   10797 | 59005 | false  | false    |          0 | mytest | utf8:33  | 3       | true       |
    | Processor0 |   28 |     126 | 10.0.102.222 | 3306 |  58192 |  45673 |   10907 | 59005 | false  | false    |          0 | mytest | utf8:33  | 3       | true       |
    | Processor0 |    8 |      86 | 10.0.102.204 | 3306 |  19028 |  43028 |   10814 | 59005 | false  | false    |          0 | mytest | utf8:33  | 3       | true       |
    | Processor0 |   16 |     128 | 10.0.102.221 | 3306 |  23193 |  45731 |   10750 | 59005 | false  | false    |          0 | mytest | utf8:33  | 3       | true       |
    | Processor0 |   24 |     121 | 10.0.102.222 | 3306 |  58187 |  48792 |   10856 | 59005 | false  | false    |          0 | mytest | utf8:33  | 3       | true       |
    | Processor0 |    4 |      79 | 10.0.102.204 | 3306 |  19021 |  41697 |   10810 | 59005 | false  | false    |          0 | mytest | utf8:33  | 3       | true       |
    | Processor1 |   13 |     123 | 10.0.102.221 | 3306 |  23189 |  45908 |   10756 | 59005 | false  | false    |          0 | mytest | utf8:33  | 3       | true       |
    | Processor1 |    5 |      82 | 10.0.102.204 | 3306 |  19024 |  42684 |   10797 | 59005 | false  | false    |          0 | mytest | utf8:33  | 3       | true       |
    | Processor1 |   25 |     128 | 10.0.102.222 | 3306 |  58194 |  45750 |   10743 | 59005 | false  | false    |          0 | mytest | latin1:5 | 3       | true       |
    | Processor1 |   17 |     125 | 10.0.102.221 | 3306 |  23191 |  46793 |   10757 | 59005 | false  | false    |          0 | mytest | utf8:33  | 3       | true       |
    | Processor1 |    9 |      87 | 10.0.102.204 | 3306 |  19029 |  42282 |   10808 | 59005 | false  | false    |          0 | mytest | utf8:33  | 3       | true       |

  • 用于查看mycat缓存。

    mysql> show @@cache;
    +-------------------------------------+-------+------+--------+------+------+-------------+----------+
    | CACHE                               | MAX   | CUR  | ACCESS | HIT  | PUT  | LAST_ACCESS | LAST_PUT |
    +-------------------------------------+-------+------+--------+------+------+-------------+----------+
    | SQLRouteCache                       | 10000 |    0 |      0 |    0 |    0 |           0 |        0 |
    | TableID2DataNodeCache.TESTDB_ORDERS | 50000 |    0 |      0 |    0 |    0 |           0 |        0 |
    | ER_SQL2PARENTID                     |  1000 |    0 |      0 |    0 |    0 |           0 |        0 |
    +-------------------------------------+-------+------+--------+------+------+-------------+----------+
    3 rows in set (0.01 sec)
    
        SQLRouteCache: SQL语句路由缓存
        TableID2DateNodeCache：缓存表主键与分片对应关系。
        ER_SQL2PARENTID：缓存ER分片中子表与父表对应关系。

  • 查看数据源的状态，如果配置了主从或者多主，则可以切换。

    mysql> show @@datasource;
    +----------+--------+-------+--------------+------+------+--------+------+------+---------+-----------+------------+
    | DATANODE | NAME   | TYPE  | HOST         | PORT | W/R  | ACTIVE | IDLE | SIZE | EXECUTE | READ_LOAD | WRITE_LOAD |
    +----------+--------+-------+--------------+------+------+--------+------+------+---------+-----------+------------+
    | dn2      | hostS2 | mysql | 10.0.102.221 | 3306 | W    |      0 |   10 | 1000 |    5956 |        11 |         17 |
    | dn3      | hostS3 | mysql | 10.0.102.204 | 3306 | W    |      0 |   10 | 1000 |    5959 |        16 |         15 |
    | dn1      | hostS1 | mysql | 10.0.102.222 | 3306 | W    |      0 |   10 | 1000 |    5962 |        12 |         22 |
    +----------+--------+-------+--------------+------+------+--------+------+------+---------+-----------+------------+
    3 rows in set (0.01 sec)

    这个命令在后面读写分离查看状态的时候会用到。

  • switch @@datasource name:index 用于切换数据源

        name: schema中配置的dataHost中的name
        index: schema中配置的dataHost的writeHost index坐标，安装从上到下的配置顺序，从0开始。
    切换数据源时会将原数据所有的连接池中的连接关闭，并且从新数据源创建新的连接，此时mycat服务不可用。
    注意：reload @@config和switch @@datasource name:index命令在执行过程中mycat服务不可用，应谨慎处理，防止正在提交的事务出错。

  • show @@syslog limit： 用于显示系统日志

    mysql> show @@syslog limit=3;
    +---------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
    | DATE                | LOG                                                                                                                                                                                                                                                       |
    +---------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
    | 2019-01-18 23:26:58 | .687  INFO [$_NIOREACTOR-1-RW] (io.mycat.net.handler.FrontendAuthenticator.success(FrontendAuthenticator.java:194)) - ServerConnection [id=23, schema=null, host=10.0.102.204, user=root,txIsolation=3, autocommit=true, schema=null]'root' login success |
    | 2019-01-18 23:26:50 | .929  INFO [$_NIOREACTOR-0-RW] (io.mycat.net.handler.FrontendAuthenticator.success(FrontendAuthenticator.java:194)) - [thread=$_NIOREACTOR-0-RW,class=ManagerConnection,id=22,host=127.0.0.1,port=9066,schema=null]'root' login success                   |
    | 2019-01-18 23:26:33 | .159  INFO [Timer0] (io.mycat.net.AbstractConnection.close(AbstractConnection.java:508)) - close connection,reason: idle  ,[thread=Timer0,class=ManagerConnection,id=20,host=127.0.0.1,port=9066,schema=null]                                             |
    +---------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
    3 rows in set (0.02 sec)
    
    端口号：该命令工作在9066端口，用来在客户端命令窗口中显示系统日志信息，通常用于远程查看mycat server的日志信息。
    参数：limit=后接正整数，该数值用来限定每次显示的日志条数的最大数值。

  • SQL统计命令

    show @@sql：显示在mycat中执行过的sql语句。
    show @@sql.slow：显示慢SQL语句。
    show @@sql.sum: 显示sql语句的整体执行情况，读写比例等。