基于keepalived实现mysql双主热备
基于keepalived实现mysql双主热备
一、环境说明
Ø Red Hat Enterprise Linux Server release 6.2或CentOS 6.4或Suse11sp1
Ø MySQL-5.1.66以上
二、单机mysql
1、安装单机mysql
1、操作说明
数据库安装需在root用户下进行操作，目前搭建mysql双主热备高可用，现提供两台服务器，服务器信息如下：10.0.2.235；10.0.2.236。首先需要在两台服务器上搭建单机版的mysql数据库。单机版的mysql数据库需要用到的安装包如下：
MySQL-server-5.5.46-1.linux2.6.x86_64.rpm，
MySQL-client-5.5.46-1.linux2.6.x86_64.rpm
2、操作指令
rpm -qa | grep mysql #检查系统残余mysql
rpm -e --nodeps * #如果有将检查出来的rpm依赖项删除
rpm –ivh MySQL-server-5.5.46-1.linux2.6.x86_64.rpm #安装mysql服务端
rpm –ivh MySQL-client-5.5.46-1.linux2.6.x86_64.rpm #安装mysql客户端
mysql_install_db --user=mysql --datadir=/usr/local/mysql/var #安装插件
chown -R mysql:mysql /var/lib/mysql #修改文件夹mysql用户权限
3、预期结果
控制台将打印如下内容：
linux-dk41:~ # rpm -ivh MySQL-server-5.5.46-1.linux2.6.x86_64.rpm
warning: MySQL-server-5.5.46-1.linux2.6.x86_64.rpm: Header V3 DSA signature: NOKEY, key ID 5072e1f5
Preparing... ########################################### [100%]
file /usr/bin/mysqlhotcopy from install of MySQL-server-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/share/man/man1/mysqlhotcopy.1.gz from install of MySQL-server-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
。。。
。。。。。。
。。。、、、、、、、、
file /usr/share/mysql/my-small.cnf from install of MySQL-server-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-5.5.31-0.7.10.x86_64
file /usr/share/mysql/mysql_system_tables.sql from install of MySQL-server-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-5.5.31-0.7.10.x86_64
file /usr/share/mysql/mysql_system_tables_data.sql from install of MySQL-server-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-5.5.31-0.7.10.x86_64
file /usr/share/mysql/mysql_test_data_timezone.sql from install of MySQL-server-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-5.5.31-0.7.10.x86_64
linux-dk41:~ # rpm -ivh MySQL-client-5.5.46-1.linux2.6.x86_64.rpm
warning: MySQL-client-5.5.46-1.linux2.6.x86_64.rpm: Header V3 DSA signature: NOKEY, key ID 5072e1f5
Preparing... ########################################### [100%]
file /usr/bin/mysql from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/bin/mysqladmin from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/bin/mysqlcheck from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/bin/mysqldump from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/bin/mysqlimport from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/bin/mysqlshow from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/share/man/man1/mysql.1.gz from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/share/man/man1/mysqladmin.1.gz from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/share/man/man1/mysqlcheck.1.gz from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/share/man/man1/mysqldump.1.gz from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/share/man/man1/mysqlimport.1.gz from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/share/man/man1/mysqlshow.1.gz from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-client-5.5.31-0.7.10.x86_64
file /usr/bin/mysqlbinlog from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-5.5.31-0.7.10.x86_64
file /usr/share/man/man1/mysqlbinlog.1.gz from install of MySQL-client-5.5.46-1.linux2.6.x86_64 conflicts with file from package mysql-5.5.31-0.7.10.x86_64
4、配置文件
1、my.cnf
首先检查在/etc路径下是否存在my.cnf配置文件
如果没有将/usr/share/mysql/下任意的my-*.cnf复制为/etc/my.cnf
cp /usr/share/mysql/my-*.cnf /etc/my.cnf
2、配置单机mysql
1、操作说明
修改mysql配置文件实现mysql默认没有密码启动然后通过客户端登陆mysql再通过sql命令修改密码。这里已经包含启动与验证部分。
2、操作指令
vim /etc/my.cnf #在my.cnf配置文件中添加参数--skip-grant-tables
service mysql restart #重新启动mysql服务
mysql #登陆mysql服务
show databases; #显示当前数据库信息
use mysql; #使用mysql数据库
select Host,User,authentication_string from user; #查询当前用户信息
grant all on *.* to 'root'@'%'; #创建远程访问root账号
注意：如果没有Host为localhost或者127.0.0.1的root用户同样创建一个
grant all on *.* to 'root'@'127.0.0.1'; #创建本地访问root账号
update set password=PASSWORD(‘123456’) where User=’root’; #修改访问密码
flush privileges; #刷新权限
quit #退出
vim /etc/my.cnf #在my.cnf中去掉参数--skip-grant-tables
service mysql restart #重启mysql服务
mysql -uroot -p #手动输入密码登陆mysql
3、预期结果
通过命令service mysql status 能够查看mysql正常启动表示启动成功
通过命令mysql -uroot -p 能成功登陆
三、双机mysql
1、操作说明
模拟两台机器 IP：10.0.2.235、IP：10.0.2.236
分别在两台服务器上安装单机版MYSQL数据库后，启动mysql数据库
在10.0.2.235、10.0.2.236服务器的数据库上分别创建数据库名： hcicpm。
在数据库上创建表和导入初始数据。
注意：以上两步确保两个数据库创建的数据库名称和数据结构相同即可。
注意：创建的数据库就是作为数据同步的数据库，如果想做多个数据库数据同步，需要创建多个数据库。
数据库的用户名和密码必须相同。
2、操作指令
如果在创建单机数据库时已经创建了root用户并用root用户作为登陆用户，下面的创建新用户并赋予权限的可以略过。
登陆10.0.2.235服务器上的数据库
linux-dk41:~ # mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 6
Server version: 5.5.31-log Source distribution
Copyright (c) 2000, 2013, 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> create user 'backup'@'%' IDENTIFIED BY '123456'; //创建数据同步用户和密码：backup/123456
Query OK, 0 rows affected (0.00 sec)
mysql> Grant replication slave on *.* to backup@'10.0.2.236' identified by '123456';
Query OK, 0 rows affected (0.00 sec)
登陆10.0.2.236服务器上的数据库
linux-dk41:/home/hcicloud/sql # mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.5.31-log Source distribution
Copyright (c) 2000, 2013, 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> create user 'backup'@'%' IDENTIFIED BY '123456';
Query OK, 0 rows affected (0.00 sec)
mysql> Grant replication slave on *.* to backup@'10.0.2.235' identified by '123456';
Query OK, 0 rows affected (0.00 sec)
2.1第一次主从搭建：
A、登陆10.0.2.235服务器（master）：
[root@localhost ~]# vim /etc/my.cnf
因为使用的是rpm包方式安装的mysql，需要将/user/share/mysql目录下的my-medium.cnf文件复制到/etc路径下并重新命名为my.cnf。
在[mysqld]下面添加如下红色字内容：
34 table_open_cache = 64
35 sort_buffer_size = 512K
36 net_buffer_length = 8K
37 read_buffer_size = 256K
38 read_rnd_buffer_size = 512K
39 myisam_sort_buffer_size = 8M
40 innodb_file_per_table=1
41 # Don't listen on a TCP/IP port at all. This can be a security enhancement,
42 # if all processes that need to connect to mysqld run on the same host.
43 # All interaction with mysqld must be made via Unix sockets or named pipes.
44 # Note that using this option without enabling named pipes on Windows
45 # (via the "enable-named-pipe" option) will render mysqld useless!
46 #
47 #skip-networking
48
49 # Replication Master Server (default)
50 # binary logging is required for replication
51 server-id=1 #服务ID 主服务器为1， 从服务器为2
52 log-bin=mysql-bin #在数据同步时，同步二进制日志
53 binlog-do-db=hcicpm #同步数据的数据库名称，有几个，就添加几行
54 log-bin-index=mysql-bin.index
55
56
57 # binary logging format - mixed recommended
58 binlog_format=mixed
59
60 # required unique id between 1 and 2^32 - 1
61 # defaults to 1 if master-host is not set
62 # but will not function as a master if omitted
63
64 # Replication Slave (comment out master section to use this)
65 #
66 # To configure this host as a replication slave, you can choose between
67 # two methods :
68 #
按[Esc] 输入【：wq】 按【Enter】
B、登陆10.0.2.236服务器（slave）：
[root@localhost ~]# vim /etc/my.cnf
在[mysqld]下面添加如下内容：
32 key_buffer_size = 16M
33 max_allowed_packet = 1M
34 table_open_cache = 64
35 sort_buffer_size = 512K
36 net_buffer_length = 8K
37 read_buffer_size = 256K
38 read_rnd_buffer_size = 512K
39 myisam_sort_buffer_size = 8M
40 innodb_file_per_table=1
41 # Don't listen on a TCP/IP port at all. This can be a security enhancement,
42 # if all processes that need to connect to mysqld run on the same host.
43 # All interaction with mysqld must be made via Unix sockets or named pipes.
44 # Note that using this option without enabling named pipes on Windows
45 # (via the "enable-named-pipe" option) will render mysqld useless!
46 #
47 #skip-networking
48
49 # Replication Master Server (default)
50 # binary logging is required for replication
51
52 server-id=2 #服务ID 主服务器为1， 从服务器为2
53 log-bin=mysql-bin
54 binlog-do-db=hcicpm
55 log-bin-index=mysql-bin.index
56
57 # binary logging format - mixed recommended
58 binlog_format=mixed
59
60 # required unique id between 1 and 2^32 - 1
61 # defaults to 1 if master-host is not set
62 # but will not function as a master if omitted
63
64 # Replication Slave (comment out master section to use this)
65 #
66 # To configure this host as a replication slave, you can choose between
按[Esc] 输入【：wq】 按【Enter】
C、分别重启主从的MYSQL数据库。
使用命令：
[root@localhost ~]# service mysql restart
Shutting down MySQL..... [确定]
Starting MySQL.... [确定]
D、登陆10.0.2.235服务器mysql
mysql> show master status;
记录结果中的：File和Position的值。例如为：mysql-bin.000008和107，后面操作会用到。
mysql> show master status;
+------------------+----------+--------------+------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000008 | 107 | hcicpm | |
+------------------+----------+--------------+------------------+
1 row in set (0.00 sec)
E、登陆10.0.2.236服务器mysql
mysql> stop slave;
Query OK, 0 rows affected (0.00 sec)
mysql> CHANGE MASTER TO MASTER_HOST="10.0.2.235",MASTER_USER="backup", MASTER_PASSWORD="123456",MASTER_LOG_FILE="mysql-bin.000008",MASTER_LOG_POS=107;
Query OK, 0 rows affected (0.01 sec)
mysql>
mysql> start slave;
Query OK, 0 rows affected (0.00 sec)
mysql> show slave status \G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 10.0.2.235
Master_User: backup
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000008
Read_Master_Log_Pos: 107
Relay_Log_File: mysqld-relay-bin.000002
Relay_Log_Pos: 253
Relay_Master_Log_File: mysql-bin.000008
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 107
Relay_Log_Space: 410
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 1
1 row in set (0.00 sec)
ERROR:
No query specified
出现如下：
Slave_IO_Running: Yes 出现：同步IO 状态显示：YES 即可
Slave_SQL_Running: Yes出现：同步服务正在运行 状态显示：yes
则说明同步成功。
2.2第二次主从搭建：
此次把236当做主，235当做从。
A、登陆10.0.2.236服务器mysql
mysql> show master status;
记录结果中的：File和Position的值。例如为：mysql-bin.000008和107，后面操作会用到.
mysql> show master status;
+------------------+----------+--------------+------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000008 | 107 | hcicpm | |
+------------------+----------+--------------+------------------+
1 row in set (0.00 sec)
B、登陆10.0.2.235服务器mysql
mysql> slave stop;
Query OK, 0 rows affected (0.01 sec)
mysql> CHANGE MASTER TO MASTER_HOST="10.0.2.236",MASTER_USER="backup", MASTER_PASSWORD="123456",MASTER_LOG_FILE="mysql-bin.000008",MASTER_LOG_POS=107;
Query OK, 0 rows affected (0.01 sec)
mysql> slave start;
Query OK, 0 rows affected (0.00 sec)
mysql> show slave status \G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 10.0.2.236
Master_User: backup
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000008
Read_Master_Log_Pos: 107
Relay_Log_File: mysqld-relay-bin.000002
Relay_Log_Pos: 253
Relay_Master_Log_File: mysql-bin.000008
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 107
Relay_Log_Space: 410
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 2
1 row in set (0.00 sec)
ERROR:
No query specified出现如下：
Slave_IO_Running: Yes 出现：同步IO 状态显示：YES 即可
Slave_SQL_Running: Yes出现：同步服务正在运行 状态显示：yes
则说明同步成功。
C、实验：在任意一台库中创建表，检查另一台库中是否自动创建了表。
同步时间取决于网络延时性 最慢5到10秒。
四、部署keepalived
1、安装keepalived
shell> cd /usr/local/src
shell> wget http://www.keepalived.org/software/keepalived-1.2.24.tar.gz
shell> tar -zxvf keepalived-1.2.24.tar.gz
shell> cd keepalived-1.2.24
shell> ./configure --prefix=/usr/local/keepalived
shell> make && make install
2、配置keepalived
安装完成后，进入安装目录的etc目录下，将keepalived相应的配置文件拷贝到系统相应的目录当中。keepalived启动时会从/etc/keepalived目录下查找keepalived.conf配置文件，如果没有找到则使用默认的配置。/etc/keepalived目录安装时默认是没有安装的，需要手动创建。配置文件目录结构如下所示：
shell> tree -l /usr/local/keepalived/etc-- keepalived
| |-- keepalived.conf
| `-- samples
| |-- keepalived.conf.status_code
| |-- keepalived.conf.track_interface
| |-- keepalived.conf.vrrp
| |-- 。。。
|-- rc.d
| `-- init.d
| `-- keepalived
`-- sysconfig
`-- keepalived
分别对应系统目录（忽略samples目录）：
/etc/keepalived/keepalived.conf
/etc/rc.d/init.d/keepalived
/etc/sysconfig/keepalived
将配置文件拷贝到系统对应的目录下：
shell> mkdir /etc/keepalived
shell> cp /usr/local/keepalived/etc/keepalived.conf /etc/keepalived/keepalived.conf
shell> cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/keepalived
shell> cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/keepalived
设置keepalived服务开机启动：
shell> chkconfig keepalived onshell> service keepalived start #启动服务shell> service keepalived stop #停止服务shell> service keepalived restart #重启服务
3、mysql与keepalived
1、操作说明
在mysql所在两台服务器上搭建keepalive服务，并修改配置文件实现监听mysql的服务。
分别修改两台keepalive.conf配置文件，主备之间的priority参数不一致
2、配置文件
2.1 keepalive.conf
linux-dk41:/etc/keepalived # mv keepalived.conf keepalived.conf.bak
linux-dk41:/etc/keepalived # vim keepalived.conf
vrrp_script chk_mysql {
script "/etc/keepalived/chk_mysql.sh" #监控脚本
interval 3
}
vrrp_instance VI_1 {
state BACKUP
interface eth1 #2.本地业务网卡名称（ip a查）
virtual_router_id 213 #3. 主备此ID保持一致（设置与tomcat不同的ID）
priority 101 #4.主备设置不同的，10.0.2.235（主）高于备
advert_int 1
authentication {
auth_type PASS
auth_pass mysql
}
virtual_ipaddress {
10.0.2.242 #5.虚拟IP1地址
}
track_script {
chk_mysql #执行上面的检查
}
}
2.2 chk_mysql.sh
mysql健康检查脚本内容如下
通过touch命令创建此文件
需要赋予chk_mysql.sh可执行权限
将此脚本放置/etc/keepalived/路径下即可。
注意赋予可执行权限。
3、启动服务
启动服务后，通过查看网卡信息，验证keepalive服务是否模拟出虚ip。
linux-dk41:/etc/keepalived # service keepalived start
Starting Keepalived daemon done
查看网卡上多出一个虚拟ip用于mysql
linux-dk41:/etc/keepalived # ip a
1: lo:
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 brd 127.255.255.255 scope host lo
inet 127.0.0.2/8 brd 127.255.255.255 scope host secondary lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth1:
link/ether 00:0c:29:f0:dc:ae brd ff:ff:ff:ff:ff:ff
inet 10.0.2.235/24 brd 10.0.2.255 scope global eth1
inet 10.0.2.242/32 scope global eth1
inet6 fe80::20c:29ff:fef0:dcae/64 scope link
valid_lft forever preferred_lft forever
3: br0:
link/ether 86:81:10:25:80:10 brd ff:ff:ff:ff:ff:ff
inet6 fe80::8481:10ff:fe25:8010/64 scope link
4、验证keepalive
搭建成功keepalive并重启后，通过service mysql stop命令宕机掉其中一台mysql,因为keepalive的检测周期配置的为3秒，故障转移时间取决于网络状况，所以再需要提供5-10秒故障发现并转移的时间。通过ip a命令查看两台服务器虚ip的情况，正常情况下虚ip会飘到活着mysql服务所在的服务器。
验证成功后，通过service mysql start恢复mysql的服务。
附keepalived配置文件（tomcat双机与mysql双机基于一个keepalived双虚ip实现）：