一,基本概念:
NDB是一种“内存中”存储引擎,它具有可用性高和数据一致性好的特点。能够使用多种故障切换和负载平衡选项配置NDB存储引擎,但以簇层面上的存储引擎开始最简单。MySQL簇的NDB存储引擎包含完整的数据集,仅取决于簇本身内的其他数据。
下面,我们介绍了设置由NDB存储引擎和一些MySQL服务器构成的MySQL簇的设置方法。
目前,MySQL簇的簇部分可独立于MySQL服务器进行配置。在MySQL簇中,簇的每个部分被视为1个节点。
有三类簇节点,在最低的MySQL簇配置中,至少有三个节点,这三类节点分别是:
管理(MGM)节点:这类节点的作用是管理MySQL簇内的其他节点,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。
数据节点:这类节点用于保存簇的数据。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。没有必要有一个以上的副本。数据节点是用命令ndbd启动的。
SQL节点:这是用来访问簇数据的节点。对于MySQL簇,客户端节点是使用NDB簇存储引擎的传统MySQL服务器。典型情况下,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。
簇配置包括对簇中单独节点的配置,以及设置节点之间的单独通信链路。对于目前设计的MySQL簇,其意图在于,从处理器的能力、内存空间和带宽来讲,存储节点是同质的,此外,为了提供单一的配置点,作为整体,簇的所有配置数据均位于1个配置文件中。
管理服务器(MGM节点)负责管理簇配置文件和簇日志。簇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。当数据节点内出现有趣的事件时,节点将关于这类事件的信息传输到管理服务器,然后,将这类信息写入簇日志。
二,配置实例:
服务器使用情况:
Node |
IP Address |
Management (MGMD) node |
192.168.0.10 |
MySQL server (SQL) node |
192.168.0.20 |
Data (NDBD) node "A" |
192.168.0.30 |
Data (NDBD) node "B" |
192.168.0.40 |
1,安装Management、Sql node、 Data node 重复以下步骤:
[root@www local]# tar -zxvf mysql-cluster-gpl-7.1.3-linux-i686-glibc23.tar.gz
[root@www local]# mv mysql-cluster-gpl-7.1.3-linux-i686-glibc23 mysql
[root@www local]# groupadd mysql
[root@www local]# useradd -g mysql mysql
[root@www local]# chown -R mysql.mysql mysql
[root@www local]# /usr/local/mysql/scripts/mysql_install_db --user=mysql
[root@www mysql]# cp support-files/mysql.server /etc/rc.d/init.d/
[root@www mysql]# chmod +x /etc/rc.d/init.d/mysql.server
[root@www mysql]# chkconfig --add mysql.server
2,配置Management节点:
[root@www mysql]# mkdir /var/lib/mysql-cluster
[root@www mysql]# vi /var/lib/mysql-cluster/config.ini
[ndbd default]
NoOfReplicas=2 # Number of replicas
DataMemory=80M # How much memory to allocate for data storage
IndexMemory=18M # How much memory to allocate for index storage
# For DataMemory and IndexMemory, we have used the
# default values. Since the "world" database takes up
# only about 500KB, this should be more than enough for
# this example Cluster setup.
# TCP/IP options:
[tcp default]
portnumber=2202 # This the default; however, you can use any port that is free
# for all the hosts in the cluster
# Note: It is recommended that you do not specify the port
# number at all and allow the default value to be used instead
# Management process options:
[ndb_mgmd]
hostname=192.168.0.10 # Hostname or IP address of management node
datadir=/var/lib/mysql-cluster # Directory for management node log files
# Options for data node "A":
[ndbd]
# (one [ndbd] section per data node)
hostname=192.168.0.30 # Hostname or IP address
datadir=/usr/local/mysql/data # Directory for this data node's data files
# Options for data node "B":
[ndbd]
hostname=192.168.0.40 # Hostname or IP address
datadir=/usr/local/mysql/data # Directory for this data node's data files
# SQL node options:
[mysqld]
hostname=192.168.0.20 # Hostname or IP address
# (additional mysqld connections can be
# specified for this node for various
# purposes such as running ndb_restore)
[root@www mysql-cluster]# cp bin/ndb_mgm* /usr/local/bin
3,配置MySQL server (SQL) node:
创建 /etc/my.cnf并添加下面的内容
#ptions for mysqld process:
[mysqld]
ndbcluster # run NDB storage engine
ndb-connectstring=192.168.0.10 # location of management server
# Options for ndbd process:
[mysql_cluster]
ndb-connectstring=192.168.0.10 # location of management server
4,配置 Data (NDBD) node "A":
创建/etc/my.cnf文件,并添加下面的内容
#ptions for mysqld process:
[mysqld]
ndbcluster # run NDB storage engine
ndb-connectstring=192.168.0.10 # location of management server
# Options for ndbd process:
[mysql_cluster]
ndb-connectstring=192.168.0.10 # location of management server
5,配置 Data (NDBD) node "B":
创建/etc/my.cnf文件,并添加下面的内容
#ptions for mysqld process:
[mysqld]
ndbcluster # run NDB storage engine
ndb-connectstring=192.168.0.10 # location of management server
# Options for ndbd process:
[mysql_cluster]
ndb-connectstring=192.168.0.10 # location of management server
6,启动Management节点:
[root@www local]# ndb_mgmd -f /var/lib/mysql-cluster/config.ini
2010-05-05 13:20:19 [MgmtSrvr] INFO -- NDB Cluster Management Server. mysql-5.1.44 ndb-7.1.3
2010-05-05 13:20:19 [MgmtSrvr] INFO -- Loaded config from '/usr/local/mysql/mysql-cluster/ndb_1_config.bin.1'
7,起动 Data (NDBD) node "A"及 Data (NDBD) node "B":
[root@www local]# /usr/local/mysql/bin/ndbd
2010-05-05 13:20:30 [ndbd] INFO -- Configuration fetched from '192.168.0.10:1186', generation: 1
8,起动 MySQL server (SQL) node
[root@www local]# /etc/init.d/mysql.server start
9,如果一切顺利,执行ndb_mgm命令之后,其输出如下:
[root@www local]# 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 @192.168.0.30 (mysql-5.1.44 ndb-7.1.3, Nodegroup: 0, Master)
id=3 @192.168.0.40 (mysql-5.1.44 ndb-7.1.3, Nodegroup: 0)
[ndb_mgmd(MGM)] 1 node(s)
id=1 @192.168.0.10 (mysql-5.1.44 ndb-7.1.3)
[mysqld(API)] 1 node(s)
id=4 @192.168.0.20 (mysql-5.1.44 ndb-7.1.3)
测试单点故障:
1,模拟NDB节点崩溃:
Data (NDBD) node "A"
[root@www ~]# netstat -tunlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.0.1:2208 0.0.0.0:* LISTEN 4456/hpiod
tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN 4240/portmap
tcp 0 0 0.0.0.0:627 0.0.0.0:* LISTEN 4261/rpc.statd
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 4487/cupsd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 4507/sendmail: acce
tcp 0 0 192.168.0.30:2202 0.0.0.0:* LISTEN 6205/ndbd
tcp 0 0 127.0.0.1:2207 0.0.0.0:* LISTEN 4461/python
tcp 0 0 :::3306 :::* LISTEN 11766/mysqld
tcp 0 0 :::22 :::* LISTEN 4476/sshd
udp 0 0 0.0.0.0:32768 0.0.0.0:* 4617/avahi-daemon:
udp 0 0 0.0.0.0:5353 0.0.0.0:* 4617/avahi-daemon:
udp 0 0 0.0.0.0:621 0.0.0.0:* 4261/rpc.statd
udp 0 0 0.0.0.0:111 0.0.0.0:* 4240/portmap
udp 0 0 0.0.0.0:624 0.0.0.0:* 4261/rpc.statd
udp 0 0 0.0.0.0:631 0.0.0.0:* 4487/cupsd
udp 0 0 :::32769 :::* 4617/avahi-daemon:
udp 0 0 :::5353 :::* 4617/avahi-daemon:
[root@www ~]# kill -9 6205
[root@www ~]# netstat -tunlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.0.1:2208 0.0.0.0:* LISTEN 4456/hpiod
tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN 4240/portmap
tcp 0 0 0.0.0.0:627 0.0.0.0:* LISTEN 4261/rpc.statd
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 4487/cupsd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 4507/sendmail: acce
tcp 0 0 127.0.0.1:2207 0.0.0.0:* LISTEN 4461/python
tcp 0 0 :::3306 :::* LISTEN 11766/mysqld
tcp 0 0 :::22 :::* LISTEN 4476/sshd
udp 0 0 0.0.0.0:32768 0.0.0.0:* 4617/avahi-daemon:
udp 0 0 0.0.0.0:5353 0.0.0.0:* 4617/avahi-daemon:
udp 0 0 0.0.0.0:621 0.0.0.0:* 4261/rpc.statd
udp 0 0 0.0.0.0:111 0.0.0.0:* 4240/portmap
udp 0 0 0.0.0.0:624 0.0.0.0:* 4261/rpc.statd
udp 0 0 0.0.0.0:631 0.0.0.0:* 4487/cupsd
udp 0 0 :::32769 :::* 4617/avahi-daemon:
udp 0 0 :::5353 :::* 4617/avahi-daemon:
[root@www ~]# kill -9
mysql> use test;
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 youshengtao;
+------+
| a |
+------+
| 400 |
| 300 |
| 200 |
| 500 |
+------+
4 rows in set (0.60 sec)
2, 在 MySQL server (SQL) node执行查询,可见down掉其中的一台data node,对cluster没有任何影响
mysql> use test;
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 youshengtao;
+------+
| a |
+------+
| 400 |
| 300 |
| 200 |
| 500 |
+------+
4 rows in set (0.60 sec)
3,模拟NDB节点崩溃:
Data (NDBD) node "B"
[root@www ~]# netstat -tunlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.0.1:2208 0.0.0.0:* LISTEN 4453/hpiod
tcp 0 0 0.0.0.0:622 0.0.0.0:* LISTEN 4256/rpc.statd
tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN 4235/portmap
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 4484/cupsd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 4504/sendmail: acce
tcp 0 0 192.168.0.40:2202 0.0.0.0:* LISTEN 6105/ndbd
tcp 0 0 127.0.0.1:2207 0.0.0.0:* LISTEN 4458/python
tcp 0 0 :::3306 :::* LISTEN 11940/mysqld
tcp 0 0 :::22 :::* LISTEN 4473/sshd
udp 0 0 0.0.0.0:32768 0.0.0.0:* 4614/avahi-daemon:
udp 0 0 0.0.0.0:616 0.0.0.0:* 4256/rpc.statd
udp 0 0 0.0.0.0:5353 0.0.0.0:* 4614/avahi-daemon:
udp 0 0 0.0.0.0:619 0.0.0.0:* 4256/rpc.statd
udp 0 0 0.0.0.0:111 0.0.0.0:* 4235/portmap
udp 0 0 0.0.0.0:631 0.0.0.0:* 4484/cupsd
udp 0 0 :::32769 :::* 4614/avahi-daemon:
udp 0 0 :::5353 :::* 4614/avahi-daemon:
[root@www ~]# kill -9 6105
[root@www ~]# netstat -tunlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.0.1:2208 0.0.0.0:* LISTEN 4453/hpiod
tcp 0 0 0.0.0.0:622 0.0.0.0:* LISTEN 4256/rpc.statd
tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN 4235/portmap
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 4484/cupsd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 4504/sendmail: acce
tcp 0 0 127.0.0.1:2207 0.0.0.0:* LISTEN 4458/python
tcp 0 0 :::3306 :::* LISTEN 11940/mysqld
tcp 0 0 :::22 :::* LISTEN 4473/sshd
udp 0 0 0.0.0.0:32768 0.0.0.0:* 4614/avahi-daemon:
udp 0 0 0.0.0.0:616 0.0.0.0:* 4256/rpc.statd
udp 0 0 0.0.0.0:5353 0.0.0.0:* 4614/avahi-daemon:
udp 0 0 0.0.0.0:619 0.0.0.0:* 4256/rpc.statd
udp 0 0 0.0.0.0:111 0.0.0.0:* 4235/portmap
udp 0 0 0.0.0.0:631 0.0.0.0:* 4484/cupsd
udp 0 0 :::32769 :::* 4614/avahi-daemon:
udp 0 0 :::5353 :::* 4614/avahi-daemon:
[root@www ~]#
4,在 MySQL server (SQL) node执行查询,data node节点全down掉之后无法进行查询了:
mysql> select * from youshengtao;
ERROR 1296 (HY000): Got error 157 'Unknown error code' from NDBCLUSTER
mysql> select * from youshengtao;
ERROR 1296 (HY000): Got error 157 'Unknown error code' from NDBCLUSTER
mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| t1 |
| youshengtao |
+----------------+
2 rows in set (0.00 sec)
mysql> desc youshengtao;
ERROR 1296 (HY000): Got error 157 'Unknown error code' from NDBCLUSTER
mysql> desc t1;
ERROR 1296 (HY000): Got error 157 'Unknown error code' from NDBCLUSTER