mycat 的简单介绍之liunx安装 ---wanzuwodou

MyCAT是mysql中间件，前身是阿里大名鼎鼎的Cobar，Cobar在开源了一段时间后，不了了之。于是MyCAT扛起了这面大旗，在大数据时代，其重要性愈发彰显。这篇文章主要是MyCAT的入门部署。

废话不说了。开始环境搭建：
Mycat是用java开发的，需要jdk不多说了，版本需要在1.7之上
jdk 官方地址：
[jdk] (http://www.oracle.com/technetwork/java/javase/archive-139210.html)
jdk安装详见：
http://blog.csdn.net/wanzuwodou/article/details/50726999

二、安装MySQL

MySQL官方下载地址如下：

http://dev.mysql.com/downloads/mysql/

mysql 安装详见：
http://blog.csdn.net/wanzuwodou/article/details/50900977
三、安装MyCAT

创建MyCAT用户并设置密码

# useradd mycat

# passwd mycat

解压MyCAT文件

 [root@cloudview2288 originalfile]# tar Mycat-server-1.4-release-20151019230038-linux.tar.gz

 mv mycat/ /usr/local/

设置mycat目录的属主和属组

 chown -R mycat.mycat /usr/local/mycat/

安装完成后：

四、测试MyCAT

首先在MySQL上创建三个数据库：db1，db2，db3。 mysql> create database db1; Query OK, 1 row affected (0.00 sec) mysql> create database db2; Query OK, 1 row affected (0.00 sec) mysql> create database db3; Query OK, 1 row affected (0.00 sec) 启动mycat服务 cd /usr/local/mycat/bin ./mycat start 

查看mycat服务是否启动

# ps -ef |grep mycat
第一次启动可能会启动不成功
cd /usr/local/mycat/logs
cat wrapper.log
会发现报错
内容大致如下：
[root@cloudview2288 bin]# cd ../logs/
[root@cloudview2288 logs]# cat wrapper.log 
STATUS | wrapper  | 2016/06/20 14:13:56 | --> Wrapper Started as Daemon
STATUS | wrapper  | 2016/06/20 14:13:56 | Launching a JVM...
INFO   | jvm 1    | 2016/06/20 14:13:56 | Error: Exception thrown by the agent : java.net.MalformedURLException: Local host name unknown: java.net.UnknownHostException: cloudview2288: cloudview2288: Name or service not known
ERROR  | wrapper  | 2016/06/20 14:13:56 | JVM exited while loading the application.
STATUS | wrapper  | 2016/06/20 14:14:00 | Launching a JVM...
ERROR  | wrapper  | 2016/06/20 14:14:01 | JVM exited while loading the application.
INFO   | jvm 2    | 2016/06/20 14:14:01 | Error: Exception thrown by the agent : java.net.MalformedURLException: Local host name unknown: java.net.UnknownHostException: cloudview2288: cloudview2288: Name or service not known
STATUS | wrapper  | 2016/06/20 14:14:05 | Launching a JVM...
INFO   | jvm 3    | 2016/06/20 14:14:05 | Error: Exception thrown by the agent : java.net.MalformedURLException: Local host name unknown: java.net.UnknownHostException: cloudview2288: cloudview2288: Name or service not known
ERROR  | wrapper  | 2016/06/20 14:14:05 | JVM exited while loading the application.

根据错误提示，是说我们的主机没有绑定。
接下来绑定hosts，vim /etc/hosts

[root@cloudview2288 bin]# cat /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
211.88.22.88 cloudview2288

绑定完hosts重新启动，然后在logs中查看日志：

[root@cloudview2288 logs]# cat wrapper.log 
STATUS | wrapper | 2016/06/20 14:15:15 | --> Wrapper Started as Daemon
STATUS | wrapper | 2016/06/20 14:15:15 | Launching a JVM...
INFO   | jvm 1 | 2016/06/20 14:15:16 | Wrapper (Version 3.2.3) http://wrapper.tanukisoftware.org
INFO   | jvm 1 | 2016/06/20 14:15:16 | Copyright 1999-2006 Tanuki Software, Inc. All Rights Reserved.
INFO   | jvm 1 | 2016/06/20 14:15:16 | 
INFO   | jvm 1 | 2016/06/20 14:15:17 | log4j 2016-06-20 14:15:17 [./conf/log4j.xml] load completed.
INFO   | jvm 1 | 2016/06/20 14:15:17 | MyCAT Server startup successfully. see logs in logs/mycat.log

说明启动成功了，并且logs中多了mycat.log日志

查看mycat的运行状态

[root@cloudview2288 bin]# ./mycat status
Mycat-server is running (18716).