架设高可用负载均衡Mysql集群-数据库-火龙果软件工程

架设高可用负载均衡Mysql集群

火龙果软件发布于 2014-07-02

一、前言

MySQL Cluster 是MySQL适合于分布式计算环境的高实用、高冗余版本。它采用了NDB Cluster存储引擎，允许在1个Cluster中运行多个MySQL服务器。在MyQL5.0 及以上的二进制版本中、以及与最新的Linux版本兼容的RPM中提供了该存储引擎。MySQL Cluster 是一种技术，该技术允许在无共享的系统中部署“内存中”数据库的 Cluster。通过无共享体系结构，系统能够使用廉价的硬件，而且对软硬件无特殊要求。此外，由于每个组件有自己的内存和磁盘，不存在单点故障。MySQL Cluster由一组计算机构成，每台计算机上均运行着多种进程，包括MySQL服务器，NDB Cluster的数据节点，管理服务器，以及（可能）专门的数据访问程序。

二、MySQL Cluster基本概念

NDB是一种“内存中”的存储引擎，它具有可用性高和数据一致性好的特点。MySQL Cluster能够使用多种故障切换和负载平衡选项配置NDB存储引擎，但在Cluster 级别上的存储引擎上做这个最简单。MySQL Cluster的NDB存储引擎包含完整的数据集，仅取决于Cluster本身内的其他数据。

目前，MySQL Cluster的Cluster部分可独立于MySQL服务器进行配置。在MySQL Cluster中，Cluster的每个部分被视为1个节点。

管理(MGM)节点：这类节点的作用是管理MySQL Cluster内的其他节点，如提供配置数据、启动并停止节点、运行备份等。由于这类节点负责管理其他节点的配置，应在启动其他节点之前首先启动这类节点。MGM节点是用命令“ndb_mgmd”启动的。

数据(NDB)节点：这类节点用于保存Cluster的数据。数据节点的数目与副本的数目相关，是片段的倍数。例如，对于两个副本，每个副本有两个片段，那么就有4个数据节点。不过没有必要设置多个副本。数据节点是用命令“ndbd”启动的。

客户(SQL)节点：这是用来访问Cluster数据的节点。对于MySQL Cluster，客户端节点是使用NDB Cluster 存储引擎的传统MySQL服务器。通常，SQL节点是使用命令“mysqld -ndbcluster”启动的，或将“ndbcluster”添加到“my.cnf”后使用“mysqld”启动。

注释：在很多情况下，术语“节点”用于指计算机，但在讨论MySQL Cluster时，它表示的是进程。在单台计算机上可以有任意数目的节点，为此，我们采用术语“Cluster主机”。

管理服务器(MGM节点)负责管理Cluster配置文件和Cluster日志。Cluster中的每个节点从管理服务器检索配置数据，并请求确定管理服务器所在位置的方式。当数据节点内出现新的事件时，节点将关于这类事件的信息传输到管理服务器，然后将这类信息写入Cluster日志。

三、环境

系统：CentOS6.4 32位 9台

软件包（可以去mysql官网下载http://dev.mysql.com/downloads/cluster/）：

MGM：

MySQL-Cluster-gpl-management-7.1.31-1.el6.i686.rpm

MySQL-Cluster-gpl-tools-7.1.31-1.el6.i686.rpm

SQL节点：

MySQL-Cluster-gpl-client-7.1.31-1.el6.i686.rpm

MySQL-Cluster-gpl-server-7.1.31-1.el6.i686.rpm

NDB节点：

MySQL-Cluster-gpl-storage-7.1.31-1.el6.i686.rpm

拓扑图：

IP规划：

四、配置（请先卸载掉与mysql有关的所有RPM包）

1.LB-Master及LB-Backup配置

(1)LB-Master及LB-Backup安装keepalived和ipvsadm

# yum groupinstall "Additional Development"         //安装开发工具   
# yum groupinstall "Development tools"   
# tar -zxvf keepalived-1.2.1.tar.gz -C /usr/local/src/   
# cd /usr/local/src/keepalived-1.2.1   
# ./cnfigure   
Keepalived configuration   
------------------------   
Keepalived version       : 1.2.1   
Compiler                 : gcc   
Compiler flags           : -g -O2   
Extra Lib                : -lpopt -lssl -lcrypto    
Use IPVS Framework       : No    //配置出现错误   
IPVS sync daemon support : No   
Use VRRP Framework       : Yes   
Use Debug flags          : No   
解决方法：   
# yum install kernel-devel ipvsadm   
# ln -s /usr/src/kernels/2.6.32-358.el6.i686/ /usr/src/linux   
# ./cnfigure                    //再次配置环境   
# make                          //编译   
# make install                  //安装   
      
# cd /usr/local/etc             //keepalived默认安装路径   
# ll   
drwxr-xr-x. 3 root root 4096 May 24 00:37 keepalived   
drwxr-xr-x. 3 root root 4096 May 24 00:29 rc.d   
drwxr-xr-x. 2 root root 4096 May 24 00:29 sysconfig   
       
配置以系统方式service启动   
# cp /usr/local/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/    
# cp /usr/local/etc/sysconfig/keepalived  /etc/sysconfig/   
# mkdir /etc/keepalived   
# cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/   
# cp /usr/local/sbin/keepalived /usr/sbin/

(2)LB-Master及LB-Backup的keepalived主配置文档

# cat /etc/keepalived/keepalived.conf   
#guration File for keepalived   
#global define   
global_defs {   
        router_id HaMySQL_1   
        }   
vrrp_sync_group VGM {   
        group {   
        VI_MYSQL   
        }   
}   
vrrp_instance VI_MYSQL {   
        state MASTER             //LB-Backup设置为BACKUP   
        interface eth0   
        lvs_sync_daemon_inteface eth0   
        virtual_router_id 55   
        priority 100             //LB-Backup设置为90   
        advert_int 5   
        authentication {   
                auth_type PASS   
                auth_pass 123456   
        }   
        virtual_ipaddress {   
                192.168.2.200/24 dev eth0   
        }   
}   
##########  LVS  MySQL Start   ###########   
virtual_server 192.168.2.200 3306 {   
        delay_loop 6   
        lb_algo rr   
        lb_kind DR   
        persistence_timeout 6   
        protocol TCP   
    
        real_server 192.168.2.50 3306 {   
                weight 100   
                TCP_CHECK {   
                        connect_timeout 3   
                        nb_get_retry 3   
                        delay_before_retry 3   
                        connect_port 3306   
                }   
        }   
        real_server 192.168.2.60 3306 {   
                weight 100   
                TCP_CHECK {   
                        connect_timeout 3   
                        nb_get_retry 3   
                        delay_before_retry 3   
                        connect_port 3306   
                }   
        }   
}   
##########  LVS MySQL END   #############

2.MGM配置

(1)安装管理节点

# rpm -ivh MySQL-Cluster-gpl-management-7.1.31-1.el6.i686.rpm   
# rpm -ivh MySQL-Cluster-gpl-tools-7.1.31-1.el6.i686.rpm    
# mkdir /etc/mysql-cluster

(2)配置管理节点

# vim /etc/mysql-cluster/config.ini     //添加以下内容   
[ndbd default]   
NoOfReplicas=2   
DataMemory=80M   
IndexMemory=18M   
# TCP/IP options:   
[tcp default]   
portnumber=2202   
# Management process options:   
[ndb_mgmd]   
id=1   
hostname=192.168.2.10   
datadir=/var/lib/mysql-cluster  
# Options for data node   
[ndbd]   
id=2   
hostname=192.168.2.30   
datadir=/var/lib/mysql  
[ndbd]   
id=3   
hostname=192.168.2.40   
datadir=/var/lib/mysql  
[mysqld]   
id=4   
hostname=192.168.2.50   
[mysqld]   
id=5   
hostname=192.168.2.60

（3）启动管理节点

# mkdir /var/lib/mysql-cluster   
# ndb_mgmd -f /etc/mysql-cluster/config.ini    
MySQL Cluster Management Server mysql-5.1.73 ndb-7.1.31   
# netstat -tupln   
tcp     0     0    0.0.0.0:1186   0.0.0.0:*   LISTEN     17629/ndb_mgmd

3.数据节点（NDB1和NDB2）配置

(1)安装数据节点

# rpm -ivh MySQL-Cluster-gpl-storage-7.1.31-1.el6.i686.rpm   
# mkdir /var/lib/mysql

(2)配置数据节点

# vim /etc/my.cnf   
[mysqld]   
datadir=/var/lib/mysql  
socket=/var/lib/mysql/mysql.sock   
user=mysql   
# Disabling symbolic-links is recommended to prevent assorted security risks   
symbolic-links=0   
    
[mysqld_safe]   
log-error=/var/log/mysqld.log   
pid-file=/var/run/mysqld/mysqld.pid   
    
[mysql_cluster]   
ndb-connectstring=192.168.2.10

（3）启动数据节点

# ndbd --initial       //NDB1   
2014-05-28 00:32:17 [ndbd] INFO     -- Angel connected to '192.168.2.10:1186' 
2014-05-28 00:32:17 [ndbd] INFO     -- Angel allocated nodeid: 2   
# ndbd --initial       //NDB2   
2014-05-28 00:33:08 [ndbd] INFO     -- Angel connected to '192.168.2.10:1186' 
2014-05-28 00:33:08 [ndbd] INFO     -- Angel allocated nodeid: 3

4.SQL节点（SQL1和SQL2）配置

网卡及屏蔽ARP设置

在现有网卡基础上添加一块lo:0网卡

# vim /etc/sysctl.conf                  //添加以下两行   
net.ipv4.conf.all.arp_announce = 2   
net.ipv4.conf.all.arp_ignore = 1   
# sysctl -p

(1)安装SQL节点

# rpm -ivh MySQL-Cluster-gpl-client-7.1.31-1.el6.i686.rpm   
# rpm -ivh MySQL-Cluster-gpl-server-7.1.31-1.el6.i686.rpm //如出错,卸载与mysql有关的rpm包

(2)配置SQL节点

# The MySQL server    
[mysqld]   
port = 3306   
socket=/var/lib/mysql/mysql.sock   
ndbcluster   
default-storage-engine=NDBCLUSTER   
skip-name-resolve   
[mysql_cluster]   
ndb-connectstring=192.168.2.10

（3）启动SQL节点

# service mysql start        //SQL1   
Starting MySQL.. SUCCESS!    
# service mysql start        //SQL2，如无法启动，执行pkill -9 mysql再启动   
Starting MySQL SUCCESS!    
# netstat -tupln |grep mysql   
tcp     0     0   0.0.0.0:3306        0.0.0.0:*     LISTEN      3475/mysqld

（4）配置远程连接(SQL1和SQL2配置一致)

# mysql   
mysql> grant all on *.* to 'nuo'@'%' identified by '123';   
mysql> flush privileges;

启动顺序一定要遵循：MGM→NDB→SQL

五、查看状态

1.查看MGM状态

# ndb_mgm   
-- NDB Cluster -- Management Client --   
ndb_mgm> show   
Connected to Management Server at: localhost:1186   
Cluster Configuration   
---------------------   
[ndbd(NDB)] 2 node(s)   
id=2    @192.168.2.30  (mysql-5.1.73 ndb-7.1.31, Nodegroup: 0, *)   
id=3    @192.168.2.40  (mysql-5.1.73 ndb-7.1.31, Nodegroup: 0)   
    
[ndb_mgmd(MGM)] 1 node(s)   
id=1    @192.168.2.10  (mysql-5.1.73 ndb-7.1.31)   
    
[mysqld(API)]   2 node(s)   
id=4    @192.168.2.50  (mysql-5.1.73 ndb-7.1.31)   
id=5    @192.168.2.60  (mysql-5.1.73 ndb-7.1.31)

2.查看LB-Master状态

# service keepalived start   
Starting keepalived:                                       [  OK  ]   
# ip addr   
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN    
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00   
    inet 127.0.0.1/8 scope host lo   
    inet6 ::1/128 scope host    
       valid_lft forever preferred_lft forever   
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 1000   
    link/ether 00:0c:29:22:3d:01 brd ff:ff:ff:ff:ff:ff   
    inet 192.168.2.20/24 brd 192.168.2.255 scope global eth0   
    inet 192.168.2.200/24 scope global secondary eth0   
    inet6 fe80::20c:29ff:fe22:3d01/64 scope link    
       valid_lft forever preferred_lft forever   
# ipvsadm   
IP Virtual Server version 1.2.1 (size=4096)   
Prot LocalAddress:Port Scheduler Flags   
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn   
TCP  192.168.2.200:mysql rr persistent 6   
  -> 192.168.2.50:mysql           Route   100    0          0            
  -> 192.168.2.60:mysql           Route   100    0          0

3.查看LB-Backup状态

# service keepalived start   
Starting keepalived:                                       [  OK  ]   
# ip addr   
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN    
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00   
    inet 127.0.0.1/8 scope host lo   
    inet6 ::1/128 scope host    
       valid_lft forever preferred_lft forever   
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 1000   
    link/ether 00:0c:29:27:e1:98 brd ff:ff:ff:ff:ff:ff   
    inet 192.168.2.21/24 brd 192.168.2.255 scope global eth0   
    inet6 fe80::20c:29ff:fe27:e198/64 scope link    
       valid_lft forever preferred_lft forever   
# ipvsadm   
IP Virtual Server version 1.2.1 (size=4096)   
Prot LocalAddress:Port Scheduler Flags   
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn   
TCP  192.168.2.200:mysql rr persistent 6   
  -> 192.168.2.50:mysql           Route   100    0          0            
  -> 192.168.2.60:mysql           Route   100    0          0

六、测试

1.客户端1（CentOS6.4 32位，IP：192.168.2.80/24）

# yum install mysql   
# mysql -h 192.168.2.200 -u nuo -p   
Enter password:   
mysql> show databases;   
+--------------------+   
| Database           |   
+--------------------+   
| information_schema |   
| mysql              |   
| ndbinfo            |   
| test               |   
+--------------------+   
mysql> create database t;   
mysql> use t;   
mysql> create table t2(id int);   
mysql> insert into t2 values(10);   
mysql> insert into t2 values(20); 
2.LB-Master查看连接状态

# ipvsadm
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 192.168.2.200:mysql rr persistent 6
-> 192.168.2.50:mysql Route 100 1 0
-> 192.168.2.60:mysql Route 100 0 0
# ipvsadm -lcn
IPVS connection entries
pro expire state source virtual destination
TCP 14:48 ESTABLISHED 192.168.2.80:49993 192.168.2.200:3306 192.168.2.50:3306
TCP 00:54 NONE 192.168.2.80:0 192.168.2.200:3306 192.168.2.50:3306

2.LB-Master查看连接状态

# ipvsadm   
IP Virtual Server version 1.2.1 (size=4096)   
Prot LocalAddress:Port Scheduler Flags   
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn   
TCP  192.168.2.200:mysql rr persistent 6   
  -> 192.168.2.50:mysql           Route   100    1          0            
  -> 192.168.2.60:mysql           Route   100    0          0            
# ipvsadm -lcn   
IPVS connection entries   
pro expire state       source             virtual            destination   
TCP 14:48  ESTABLISHED 192.168.2.80:49993 192.168.2.200:3306 192.168.2.50:3306   
TCP 00:54  NONE        192.168.2.80:0     192.168.2.200:3306 192.168.2.50:3306

3.客户端2（CentOS6.4 32位，IP：192.168.2.81/24）

# yum install mysql   
# mysql -h 192.168.2.200 -u nuo -p   
Enter password:   
mysql> show databases;   
+--------------------+   
| Database           |   
+--------------------+   
| information_schema |   
| mysql              |   
| ndbinfo            |   
| t                  |   
| test               |   
+--------------------+   
mysql> use t;   
mysql> select * from t2;   
+------+   
| id   |   
+------+   
|   20 |   
|   10 |   
+------+

4.LB-Master查看连接状态

# ipvsadm -lcn   
IPVS connection entries   
pro expire state       source             virtual            destination   
TCP 00:36  NONE        192.168.2.81:0     192.168.2.200:3306 192.168.2.60:3306   
TCP 14:18  ESTABLISHED 192.168.2.81:42435 192.168.2.200:3306 192.168.2.60:3306

总结：在客户端1上插入数据后，服务器显示客户端1连接的是SQL1(192.168.2.50),在客户端2上进行查询，能查询到客户端1输入的数据，服务器显示客户端2连接的是SQL2（192.168.2.60），所以，数据是同步的，并且是一致性的。

次浏览