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mycat實(shí)驗(yàn)之主從配置讀寫(xiě)分離和分表
1.實(shí)驗(yàn)環(huán)境：
vmware虛機(jī)3個(gè) （虛機(jī)太少了，電腦有點(diǎn)吃力，3個(gè)虛機(jī)只能達(dá)到基本的測(cè)試）
系統(tǒng)centos7 （實(shí)驗(yàn)是關(guān)閉防火墻和selinux做的）
mysql版本5.7
mycat版本1.6
虛機(jī)名字和ip：
mysql1 192.168.211.138
mysql2 192.168.211.139
mysql3 192.168.211.142
mycat安裝在mysql1(192.168.211.138)
這臺(tái)主機(jī)須能夠解析mysql2,mysql3的地址。
可通過(guò)/etc/hosts 手動(dòng)添加解析
2.實(shí)驗(yàn)?zāi)康?br/>
實(shí)現(xiàn)mycat讀寫(xiě)分離和分表的功能。
3.實(shí)驗(yàn)思路
在mycat創(chuàng)建一個(gè)邏輯庫(kù)：hello。
創(chuàng)建四個(gè)表格：
t1 這個(gè)表格用來(lái)分片，用枚舉的規(guī)則分片。
t2 這個(gè)表格做全局表。
t3 這個(gè)表格做普通表，定義它放到其中一個(gè)datanode,放到mysql1
t4 這個(gè)表格做普通表，定義它放到其中一個(gè)datanode,放到mysql3
虛機(jī)的分配：
mysql1 和mysql2做主從配置，其中mysql1為主，mysql2為從,其中mysql1用來(lái)寫(xiě)，mysql2用來(lái)讀。
mysql3 就是個(gè)單獨(dú)的datanode
實(shí)際我們只有兩個(gè)datanode，mysql1,mysql3。
4.實(shí)驗(yàn)步驟
分別在虛機(jī)安裝mysql5.7，步驟略。
設(shè)置mysql用戶，步驟略。請(qǐng)注意，必須設(shè)置一個(gè)用戶允許內(nèi)網(wǎng)地址連接或者干脆是允許任何地方連接。比如設(shè)置'root'@'%'。
安裝mycat。步驟略。
配置mysql1和mysql2主從，步驟略。
以上都是些常用配置，懶得特意記錄了。
以上的環(huán)境都配置好了，就可以開(kāi)始我們實(shí)驗(yàn)核心步驟mycat的配置了
現(xiàn)在開(kāi)始整個(gè)過(guò)程的配置。
1.在mysql1（192.168.211.138）里創(chuàng)建一個(gè)db1.
mysql> create database db1; Query OK, 1 row affected (0.01 sec)
檢查mysql2（192.168.211.139）里是不是同步了？
mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | db1 | | logs | | mysql | | performance_schema | | sys | | wordpress | +--------------------+ 7 rows in set (0.00 sec)
同步了。
2.在mysql3（192.168.211.142）里創(chuàng)建db2。
mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | db2 | | logs | | mysql | | performance_schema | | sys | | wordpress | +--------------------+ 7 rows in set (0.01 sec)
3.在mysql1里配置mycat，我的mycat安裝在mysql1。
我的配置文件路徑：
[root@mysql1 conf]# pwd /usr/local/mycat/conf
主要配置文件有：
[root@mysql1 conf]# ls autopartition-long.txt log4j2.xml schema.xml.bk server.xml.bk auto-sharding-long.txt migrateTables.properties schema.xml.bk2 sharding-by-enum.txt auto-sharding-rang-mod.txt myid.properties sequence_conf.properties wrapper.conf cacheservice.properties partition-hash-int.txt sequence_db_conf.properties zkconf dnindex.properties partition-range-mod.txt sequence_distributed_conf.properties zkdownload ehcache.xml rule.xml sequence_time_conf.properties index_to_charset.properties schema.xml server.xml [root@mysql1 conf]#
需要用到的是:schema.xml ##這個(gè)文件配置分表讀寫(xiě)分離策略
rule.xml ##這是分表規(guī)則的定義
server.xml ##登錄mycat的賬戶密碼和防火墻的設(shè)置
4.首先配置：schema.xml
備份下原配置文件：
[root@mysql1 conf]# cp schema.xml schema.xml.bk3
清空配置文件：
[root@mysql1 conf]# echo " " >schema.xml
重新配置schema.xml，如下是我的配置文件整個(gè)內(nèi)容:
<?xml version="1.0"?> <!DOCTYPE mycat:schema SYSTEM "schema.dtd"> <mycat:schema xmlns:mycat="http://io.mycat/"> <schema name="hello" checkSQLschema="false" sqlMaxLimit="100"> <!-- auto sharding by id (long) --> <table name="t1" dataNode="dn1,dn2" rule="sharding-by-intfile" /> <!-- global table is auto cloned to all defined data nodes ,so can join with any table whose sharding node is in the same data node --> <table name="t2" primaryKey="ID" type="global" dataNode="dn1,dn2" /> <table name="t3" dataNode="dn1" /> <table name="t4" dataNode="dn2" /> </schema> <!-- <dataNode name="dn1$0-743" dataHost="localhost1" database="db$0-743" /> --> <dataNode name="dn1" dataHost="mysql1" database="db1" /> <dataNode name="dn2" dataHost="mysql3" database="db2" /> <dataHost name="mysql1" maxCon="1000" minCon="10" balance="3" writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100"> <heartbeat>select user()</heartbeat> <!-- can have multi write hosts --> <writeHost host="hostM1" url="192.168.211.138:3306" user="root" password="Alex2010@"> <!-- can have multi read hosts --> <readHost host="hostS2" url="192.168.211.139:3306" user="root" password="Alex2010@"/> </writeHost> </dataHost> <dataHost name="mysql3" maxCon="1000" minCon="10" balance="0" writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100"> <heartbeat>select user()</heartbeat> <!-- can have multi write hosts --> <writeHost host="hostM1" url="192.168.211.142:3306" user="root" password="Alex2010@"> <!-- can have multi read hosts --> <readHost host="hostS2" url="192.168.211.142:3306" user="root" password="Alex2010@"/> </writeHost> </dataHost> </mycat:schema>
這些字段的解釋，可以查看我前面分片規(guī)則里面的解析。
說(shuō)明下datahost balance字段的意義
balance屬性
負(fù)載均衡類型，目前的取值有3種：
1. balance="0", 不開(kāi)啟讀寫(xiě)分離機(jī)制，所有讀操作都發(fā)送到當(dāng)前可用的writeHost上。
2. balance="1"，全部的readHost與stand by writeHost參與select語(yǔ)句的負(fù)載均衡，簡(jiǎn)單的說(shuō)，當(dāng)雙主雙從模式(M1->S1，M2->S2，并且M1與
M2互為主備)，正常情況下，M2,S1,S2都參與select語(yǔ)句的負(fù)載均衡。
3. balance="2"，所有讀操作都隨機(jī)的在writeHost、readhost上分發(fā)。
4. balance="3"，所有讀請(qǐng)求隨機(jī)的分發(fā)到wiriterHost對(duì)應(yīng)的readhost執(zhí)行，writerHost不負(fù)擔(dān)讀壓
writeType屬性
負(fù)載均衡類型，目前的取值有3種：
1. writeType="0", 所有寫(xiě)操作發(fā)送到配置的第一個(gè)writeHost，第一個(gè)掛了切到還生存的第二個(gè)writeHost，重新啟動(dòng)后已切換后的為準(zhǔn)，
切換記錄在配置文件中:dnindex.properties .
2. writeType="1"，所有寫(xiě)操作都隨機(jī)的發(fā)送到配置的writeHost，1.5以后廢棄不推薦。
需要說(shuō)明的是：
<dataHost name="mysql1" maxCon="1000" minCon="10" balance="3" writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100"> <heartbeat>select user()</heartbeat> <!-- can have multi write hosts --> <writeHost host="hostM1" url="192.168.211.138:3306" user="root" password="Alex2010@"> <!-- can have multi read hosts --> <readHost host="hostS2" url="192.168.211.139:3306" user="root" password="Alex2010@"/> </writeHost> </dataHost>
讀寫(xiě)分離這里有兩種寫(xiě)法：
除了上面的還可以寫(xiě)下面這樣：
<dataHost name="mysql1" maxCon="1000" minCon="10" balance="3" writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100"> <heartbeat>select user()</heartbeat> <!-- can have multi write hosts --> <writeHost host="hostM1" url="192.168.211.138:3306" user="root" password="Alex2010@"> </writeHost> <writeHost host="hostM1" url="192.168.211.139:3306" user="root" password="Alex2010@"> </writeHost> </dataHost>
區(qū)別是上面的那種寫(xiě)法，如果主服務(wù)器掛了，從服務(wù)器不能讀了。
下面的這種寫(xiě)法，主服務(wù)器掛了，從服務(wù)器依然可以正常讀取。
這里說(shuō)一下，后面會(huì)做測(cè)試。
5.看看rule.xml里的配置
看分表t1的設(shè)置：
<table name="t1" dataNode="dn1,dn2" rule="sharding-by-intfile" />
分表規(guī)則是 sharding-by-intfile
看看這個(gè)的規(guī)則設(shè)置
<tableRule name="sharding-by-intfile"> <rule> <columns>city</columns> <algorithm>hash-int</algorithm> </rule> </tableRule>
為什么columns是city呢？
這個(gè)city是我設(shè)定的，計(jì)劃創(chuàng)建表格t1(id,name,bu,city)有這四個(gè)列。我準(zhǔn)備用city來(lái)做分片的列。
繼續(xù)往下看
</function> <function name="hash-int" class="io.mycat.route.function.PartitionByFileMap"> <property name="mapFile">partition-hash-int.txt</property> <property name="type">1</property> <property name="defaultNode">0</property> </function>
這是用的hash-int函數(shù)的設(shè)置了。其中mpfile是指要讀取的配置文件。這是什么意思呢？
看看partition-hash-int.txt的內(nèi)容
[root@mysql1 conf]# cat partition-hash-int.txt #10000=0 #10010=1 bj=0 gz=0 sz=1 [root@mysql1 conf]#
我計(jì)劃的表格t1 city列有三個(gè)值，bj gz sz ，這個(gè)設(shè)置的意思是：bj gz 的數(shù)據(jù)存儲(chǔ)到datanode1也就是mysql1，sz的數(shù)據(jù)存儲(chǔ)
到datanode2也就是mysql3。
<property name="type">1</property> <property name="defaultNode">0</property>
這兩條參數(shù)也必須要有，type默認(rèn)的值是0，而0的格式是interger，注意我們分片的列是city是字符。
6.配置server.xml，參考下官方教程，很簡(jiǎn)單。
7.到這里可以來(lái)啟動(dòng)mycat，登錄進(jìn)去創(chuàng)建表格，插入數(shù)據(jù)測(cè)試，是不是能夠達(dá)到我們的預(yù)期目標(biāo)？
[root@mysql1 conf]# mysql -uroot -p123456 -P8066 -h 127.0.0.1 mysql: [Warning] Using a password on the command line interface can be insecure. Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 2 Server version: 5.6.29-mycat-1.6-RELEASE-20161028204710 MyCat Server (OpenCloundDB) Copyright (c) 2000, 2017, 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>
登錄進(jìn)來(lái)了
mysql> show databases; +----------+ | DATABASE | +----------+ | hello | +----------+ 1 row in set (0.02 sec) mysql>
我們?cè)O(shè)置的邏輯庫(kù)hello
mysql> use hello; Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A Database changed mysql> show tables; +-----------------+ | Tables in hello | +-----------------+ | t1 | | t2 | | t3 | | t4 | +-----------------+ 4 rows in set (0.01 sec) mysql> mysql> desc t1; ERROR 1146 (42S02): Table 'db1.t1' doesn't exist mysql>
注意這里有個(gè)問(wèn)題，這些t1-t4的表格，看似是有，其實(shí)是假的。感覺(jué)像是BUG。表格需要我們手動(dòng)創(chuàng)建。
創(chuàng)建表格：
mysql> create table t1 (id int not null,name varchar(15) not null,bu varchar(10) not null,city varchar(5) not null); Query OK, 0 rows affected (0.36 sec) mysql> create table t2 (id int not null,name varchar(15) not null); Query OK, 0 rows affected (0.10 sec) mysql> create table t3 (id int not null,gongzi int not null); Query OK, 0 rows affected (0.07 sec) mysql> create table t4 (id int not null,shui int not null); Query OK, 0 rows affected (0.07 sec)
看看創(chuàng)建的表格都放在哪?
mysql> explain create table t1 (id int not null,name varchar(15) not null,bu varchar(10) not null,city varchar(5) not null); +-----------+--------------------------------------------------------------------------------------------------------------+ | DATA_NODE | SQL | +-----------+--------------------------------------------------------------------------------------------------------------+ | dn1 | create table t1 (id int not null,name varchar(15) not null,bu varchar(10) not null,city varchar(5) not null) | | dn2 | create table t1 (id int not null,name varchar(15) not null,bu varchar(10) not null,city varchar(5) not null) | +-----------+--------------------------------------------------------------------------------------------------------------+ 2 rows in set (0.00 sec) mysql>
這是分片表，dn1,dn2都有
mysql> explain create table t2 (id int not null,name varchar(15) not null); +-----------+-------------------------------------------------------------+ | DATA_NODE | SQL | +-----------+-------------------------------------------------------------+ | dn1 | create table t2 (id int not null,name varchar(15) not null) | | dn2 | create table t2 (id int not null,name varchar(15) not null) | +-----------+-------------------------------------------------------------+ 2 rows in set (0.00 sec) mysql>
這是全局表，dn1,dn2都有，全局表的意思是，每個(gè)dn節(jié)點(diǎn)都有的表而且數(shù)據(jù)保持一致。
mysql> explain create table t3 (id int not null,gongzi int not null); +-----------+-------------------------------------------------------+ | DATA_NODE | SQL | +-----------+-------------------------------------------------------+ | dn1 | create table t3 (id int not null,gongzi int not null) | +-----------+-------------------------------------------------------+ 1 row in set (0.00 sec) mysql>
普通表，預(yù)設(shè)就是放在dn1，正常
mysql> explain create table t4 (id int not null,shui int not null); +-----------+------------------------------------------------------+ | DATA_NODE | SQL | +-----------+------------------------------------------------------+ | dn2 | create table t4 (id int not null,shui int not null) | +-----------+------------------------------------------------------+ 1 row in set (0.00 sec) mysql>
普通表，預(yù)設(shè)就是放在dn2，正常
看看從庫(kù)的情況：
mysql> show tables; +---------------+ | Tables_in_db1 | +---------------+ | t1 | | t2 | | t3 | +---------------+ 3 rows in set (0.00 sec) mysql>
除了t4沒(méi)有，其他都有，正常。
插入數(shù)據(jù)：
插入t1
mysql> insert into t1(id,name,bu,city)values(1,'am1','sy','bj'); Query OK, 1 row affected (0.38 sec) mysql> insert into t1(id,name,bu,city)values(2,'am2','cs','gz'); Query OK, 1 row affected (0.03 sec) mysql> insert into t1(id,name,bu,city)values(3,'am3','net','sz'); Query OK, 1 row affected (0.08 sec) mysql>
插入t2
mysql> insert into t2(id,name)value(4,'am4'),(5,'am5'); Query OK, 2 rows affected (0.11 sec) Records: 2 Duplicates: 0 Warnings: 0
插入t3
mysql> insert into t3(id,gongzi)values(6,1000),(7,1200); Query OK, 2 rows affected (0.02 sec) Records: 2 Duplicates: 0 Warnings: 0
插入t4
mysql> insert into t4(id,shui)values(8,10),(9,8); Query OK, 2 rows affected (0.04 sec) Records: 2 Duplicates: 0 Warnings: 0
基礎(chǔ)架構(gòu)和環(huán)境以及達(dá)成，現(xiàn)在來(lái)測(cè)試：
首先，t1根據(jù)預(yù)設(shè)的目的，bj和gz的數(shù)據(jù)存放在dn1(mysql1),sz的數(shù)據(jù)存放在dn2(mysql3)
mysql> select * from t1 where city='bj' or city='gz'; +----+------+----+------+ | id | name | bu | city | +----+------+----+------+ | 1 | am1 | sy | bj | | 2 | am2 | cs | gz | +----+------+----+------+ 2 rows in set (0.10 sec) mysql> explain select * from t1 where city='bj' or city='gz'; +-----------+--------------------------------------------------------------+ | DATA_NODE | SQL | +-----------+--------------------------------------------------------------+ | dn1 | SELECT * FROM t1 WHERE city = 'bj' OR city = 'gz' LIMIT 100 | +-----------+--------------------------------------------------------------+ 1 row in set (0.00 sec) mysql> mysql> explain select * from t1 where city='sz'; +-----------+----------------------------------------------+ | DATA_NODE | SQL | +-----------+----------------------------------------------+ | dn2 | SELECT * FROM t1 WHERE city = 'sz' LIMIT 100 | +-----------+----------------------------------------------+ 1 row in set (0.02 sec) mysql>
分表正常
測(cè)試讀寫(xiě)分離
開(kāi)啟debug日志
<asyncRoot level="debug" includeLocation="true"> ##默認(rèn)level是info 改成debug后，重啟mycat服務(wù)。 <AppenderRef ref="Console" /> <AppenderRef ref="RollingFile"/> </asyncRoot>
檢索數(shù)據(jù)：
檢索t3的數(shù)據(jù)，t3只有mysql1有。
mysql> select * from t3; +----+--------+ | id | gongzi | +----+--------+ | 6 | 1000 | | 7 | 1200 | +----+--------+ 2 rows in set (0.02 sec)
以下是mycat.log日志，可以看到是從mysql2(192.168.211.139)讀取的數(shù)據(jù)
2017-12-15 01:47:23.280 DEBUG [$_NIOREACTOR-0-RW] (io.mycat.server.NonBlockingSession.releaseConnection(NonBlockingSession.java:341))
- release connection MySQLConnection [id=22, lastTime=1513320443251, user=root, schema=db1, old shema=db1, borrowed=true,
fromSlaveDB=true, threadId=33, charset=utf8, txIsolation=3, autocommit=true, attachment=dn1{SELECT *
FROM t3
LIMIT 100}, respHandler=SingleNodeHandler [node=dn1{SELECT *
FROM t3
LIMIT 100}, packetId=6], host=192.168.211.139, port=3306, statusSync=null, writeQueue=0, modifiedSQLExecuted=false]
2017-12-15 01:54:37.777 DEBUG [$_NIOREACTOR-0-RW] (io.mycat.server.NonBlockingSession.releaseConnection(NonBlockingSession.java:341))
- release connection MySQLConnection [id=26, lastTime=1513320877751, user=root, schema=db1, old shema=db1, borrowed=true, fromSlaveDB=true,
threadId=31, charset=utf8, txIsolation=3, autocommit=true, attachment=dn1{SELECT *
FROM t3
LIMIT 100}, respHandler=SingleNodeHandler [node=dn1{SELECT *
FROM t3
LIMIT 100}, packetId=6], host=192.168.211.139, port=3306, statusSync=null, writeQueue=0, modifiedSQLExecuted=false]mysql> select * from t1; +----+------+-----+------+ | id | name | bu | city | +----+------+-----+------+ | 3 | am3 | net | sz | | 1 | am1 | sy | bj | | 2 | am2 | cs | gz | +----+------+-----+------+ 3 rows in set (0.04 sec)
日志
2017-12-15 02:02:35.818 DEBUG [$_NIOREACTOR-0-RW] (io.mycat.backend.mysql.nio.MySQLConnection.synAndDoExecute(MySQLConnection.java:448))
- con need syn ,total syn cmd 1 commands SET names utf8;schema change:false con:MySQLConnection [id=29, lastTime=1513321355817, user=root,
schema=db1, old shema=db1, borrowed=true, fromSlaveDB=true, threadId=35, charset=utf8, txIsolation=3, autocommit=true, attachment=dn1{SELECT *
FROM t1
LIMIT 100}, respHandler=io.mycat.backend.mysql.nio.handler.MultiNodeQueryHandler@11eaaf37, host=192.168.211.139, port=3306, statusSync=null, writeQueue=0,
modifiedSQLExecuted=false]
2017-12-15 02:02:35.819 DEBUG [$_NIOREACTOR-0-RW] (io.mycat.backend.mysql.nio.MySQLConnection.synAndDoExecute(MySQLConnection.java:448))
- con need syn ,total syn cmd 1 commands SET names utf8;schema change:false con:MySQLConnection [id=20, lastTime=1513321355819, user=root,
schema=db2, old shema=db2, borrowed=true, fromSlaveDB=false, threadId=65, charset=utf8, txIsolation=3, autocommit=true, attachment=dn2{SELECT *
FROM t1
LIMIT 100}, respHandler=io.mycat.backend.mysql.nio.handler.MultiNodeQueryHandler@11eaaf37, host=192.168.211.142, port=3306, statusSync=null, writeQueue=0,
modifiedSQLExecuted=false]多執(zhí)行幾次檢索存在dn1的數(shù)據(jù)，查看日志，可以確認(rèn)，數(shù)據(jù)都是從mysql2(192.168.211.139)讀取。實(shí)現(xiàn)了讀寫(xiě)分離。
8.讀寫(xiě)兩種不同寫(xiě)法的測(cè)試
前面有提到讀寫(xiě)分離有兩種寫(xiě)法，
<dataHost name="mysql1" maxCon="1000" minCon="10" balance="3" writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100"> <heartbeat>select user()</heartbeat> <!-- can have multi write hosts --> <writeHost host="hostM1" url="192.168.211.138:3306" user="root" password="Alex2010@"> <!-- can have multi read hosts --> <readHost host="hostS2" url="192.168.211.139:3306" user="root" password="Alex2010@"/> </writeHost> </dataHost>
讀寫(xiě)分離這里有兩種寫(xiě)法：
除了上面的還可以寫(xiě)下面這樣：
<dataHost name="mysql1" maxCon="1000" minCon="10" balance="3" writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100"> <heartbeat>select user()</heartbeat> <!-- can have multi write hosts --> <writeHost host="hostM1" url="192.168.211.138:3306" user="root" password="Alex2010@"> </writeHost> <writeHost host="hostM1" url="192.168.211.139:3306" user="root" password="Alex2010@"> </writeHost> </dataHost>
區(qū)別是上面的那種寫(xiě)法，如果主服務(wù)器掛了，從服務(wù)器不能讀了。
下面的這種寫(xiě)法，主服務(wù)器掛了，從服務(wù)器依然可以正常讀取。
現(xiàn)在服務(wù)器的寫(xiě)法是第一種，主服務(wù)器掛了，從服務(wù)器不能讀了。執(zhí)行看看
[root@mysql1 ~]# systemctl stop mysqld.service [root@mysql1 ~]# systemctl status mysqld.service ● mysqld.service - MySQL Server Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled) Active: inactive (dead) since Fri 2017-12-15 02:16:43 EST; 35s ago Docs: man:mysqld(8)
[root@mysql1 ~]# mysql -uroot -p123456 -P8066 -h227.0.0.1 mysql: [Warning] Using a password on the command line interface can be insecure. Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 2 Server version: 5.6.29-mycat-1.6-RELEASE-20161028204710 MyCat Server (OpenCloundDB) Copyright (c) 2000, 2017, 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> select * from t1; ERROR 3000 (HY000): No MyCAT Database selected mysql> select * from t1; ERROR 3000 (HY000): No MyCAT Database selected
確實(shí)無(wú)法讀取
測(cè)試第二種
修改schema.xml配置文件
重新啟動(dòng)mysql和mycat 保證環(huán)境正常
正常使用環(huán)境，我們現(xiàn)在關(guān)閉mysql1就是主節(jié)點(diǎn)
[root@mysql1 conf]# systemctl stop mysqld.service [root@mysql1 conf]# systemctl status mysqld.service ● mysqld.service - MySQL Server Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled) Active: inactive (dead) since Fri 2017-12-15 02:23:55 EST; 23s ago Docs: man:mysqld(8)
檢索數(shù)據(jù)看看
[root@mysql1 ~]# mysql -uroot -p123456 -P8066 -h227.0.0.1 mysql: [Warning] Using a password on the command line interface can be insecure. Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 1 Server version: 5.6.29-mycat-1.6-RELEASE-20161028204710 MyCat Server (OpenCloundDB) Copyright (c) 2000, 2017, 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> use hello; Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A Database changed mysql> select * from t1; +----+------+-----+------+ | id | name | bu | city | +----+------+-----+------+ | 3 | am3 | net | sz | | 1 | am1 | sy | bj | | 2 | am2 | cs | gz | +----+------+-----+------+ 3 rows in set (0.46 sec)
果然如此，孰優(yōu)孰劣無(wú)須說(shuō)明了吧。
后記：通過(guò)環(huán)境的搭建和簡(jiǎn)單的測(cè)試，達(dá)到了設(shè)計(jì)的預(yù)期目標(biāo)。
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