每台主机均需安装keepalived，mysql，安装过程这里不多介绍，不懂的可自行百度。
本次配置的环境为
DB1：192.168.31.190 DB2：192.168.31.184 MySQL VIP：192.168.31.189
1、修改MySQL配置文件
首先修改DB1的/etc/my.cnf配置文件，在"[mysqld]"段中添加一下内容：
server-id = 1
log-bin=mysql-bin
relay-log = mysql-relay-bin
replicate-wild-ignore-table=mysql.%
replicate-wild-ignore-table=test.%
replicate-wild-ignore-table=information_schema.%
然后修改DB2主机/etc/my.cnf配置文件,在"[mysqld]"段添加一下内容:
server-id = 2
log-bin=mysql-bin
relay-log = mysql-relay-bin
replicate-wild-ignore-table=mysql.%
replicate-wild-ignore-table=test.%
replicate-wild-ignore-table=information_schema.%
2、手动同步数据库
DB1和DB2数据需要保持同步，在DB1上执行操作
mysql> FLUSH TABLES WITH READ LOCK; Query OK,0 rows affected (0.00 sec) #然后不要退出终端，重开一个终端，执行一下命令 # cd /var/lib/ # tar zcvf mysql.tar.gz mysql # scp mysql.tar.gz DB2:/var/lib/
将数据传输到DB2后解压覆盖然后依次重启DB1和DB2上的MySQL
3、创建复制用户并授权
在DB1MySQL执行如下操作：
mysql> grant replication slave on *.* to ‘repl_user‘@‘192.168.31.184‘ identified by ‘repl_passwd‘; mysql> show master status;
然后在DB2的MySQL将DB1设为自己的主服务器，操作如下：
mysql> change master to -> master_host=‘192.168.31.190‘,
-> master_user=‘repl_user‘,
-> master_password=‘repl_passwd‘,
-> master_log_file=‘mysql-bin.000001‘,
-> master_log_pos=106;
#接着启动slave服务
mysql> start slave；#查看slave运行状态
mysql> show slave status\G;
到这里，从DB1到DB2的MySQL主从复制已经完成，接下来配置DB2到DB1的mysql主从复制，过程和上面完全一样，在DB2的MySQL创建复制用户：
mysql> grant replication slave on *.* to ‘repl_user‘@‘192.168.31.190‘ identified by ‘repl_passwd‘; mysql> show master status;
然后在DB1的MySQL将DB2设为自己的主服务器：
mysql> change master to -> master_host=‘192.168.31.184‘,
-> master_user=‘repl_user‘,
-> master_password=‘repl_passwd‘,
-> master_log_file=‘mysql-bin.000001‘,
-> master_log_pos=436;
mysql> start slave；
mysql> show slave status\G;
接着启动slave服务。至此，MySQL双主模式的主从复制配置完毕。
4、配置keepalived实现MySQL双主高可用
首先在DB1上配置/etc/keepalived/keepalived.conf，内容如下
global_defs {
notification_email {
[email protected]
[email protected]
[email protected]
}
notification_email_from [email protected]
smtp_server 192.168.200.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_script check_mysqld {
script "/etc/keepalived/mysqlcheck/check_slave.pl 127.0.0.1"#检测mysql复制状态脚本
interval 2
weight 21
}
vrrp_instance HA_1 {
state BACKUP #在DB1和DB2均为BACKUP
interface eth1
virtual_router_id 80
priority 100
advert_int 2
nopreempt #不抢占模式，只在优先级高的机器设置
authentication {
auth_type PASS
auth_pass qweasdzxc
track_script {
check_mysqld
}
virtual_ipaddress {
192.168.31.189/24 dev eth1 #mysql对外服务IP，即VIP
}
}
其中，/etc/keepalived/mysqlcheck/check_slave.pl文件的内容如下：
#!/usr/bin/perl -w
use DBI;
use DBD::mysql;
#CONFIG VARIABLES
$SBM = 120;
$db = "ixdba";
$host = $ARGV[0];
$port = 3306;
$user = "root";
$pw = "915389546";
#SQL query
$query = "show slave status";
$dbh = DBI->connect("DBI:mysql:$db:$host:$port",$user,$pw,{ RaiseError => 0,PrintError => 0 });
if (!defined($dbh)) {
exit 1;
}
$sqlQuery = $dbh->prepare($query);
$sqlQuery->execute;
$Slave_IO_Running = "";
$Slave_SQL_Running = "";
$Seconds_Behind_Master = "";
while (my $ref = $sqlQuery->fetchrow_hashref()) {
$Slave_IO_Running = $ref->{‘Slave_IO_Running‘};
$Slave_SQL_Running = $ref->{‘Slave_SQL_Running‘};
$Seconds_Behind_Master = $ref->{‘Second_Behind_Master‘};
}
$sqlQuery->finish;
$dbh->disconnect();
if ( $Slave_IO_Running eq "NO" || $Slave_SQL_Running eq "NO" ) {
exit 1;
} else {
if ( $Seconds_Behind__Master > $SBM) {
exit 1;
} else {
exit 0;
}
}
接着将keepalived和check_slave.pl复制到DB2服务器上对应的位置，然后将keepalived文件中的priority值修改为90，还需去掉nopreempt选项，然后分别在DB1和DB2上启动keepalived服务。
5、测试主从同步功能
首先从第三台服务器远程登录VIP为“192.168.31.188“的数据库，操作过程如下：
[[email protected]~]#mysql -uroot -p -h 192.168.31.188Enter password: MySQL [(none)]> show variables like "%hostname%"; +---------------+----------------+ | Variable_name | Value | +---------------+----------------+ | hostname | DB1 | +---------------+----------------+ 1 row in set (0.01 sec) MySQL [(none)]> show variables like "%server_id%"; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | server_id | 1 | +---------------+-------+ 1 row in set (0.01 sec)#可以看到成功通过VIP登录，并且登录了DB1服务器。#接下来测试复制数据功能 MySQL [(none)]> create database repldb; Query OK, 1 row affected (0.12 sec) MySQL [(none)]> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | repldb | | test | +--------------------+ 5 rows in set (0.01 sec) MySQL [(none)]> use repldb; Database changed MySQL [repldb]> create table repl_table(id int,email varchar(80),password varchar(40) not null); Query OK, 0 rows affected (0.03 sec) MySQL [repldb]> show tables; +------------------+ | Tables_in_repldb | +------------------+ | repl_table | +------------------+ 1 row in set (0.00 sec) MySQL [repldb]> insert into repl_table (id,email,password) values(1,"[email protected]","123456"); Query OK, 1 row affected (0.00 sec)
然后登录DB2主机的MySQL查看，可以发现数据实现了同步。
6、故障转移测试
首先远程通过VIP地址登录MySQL系统，不要退出这个连接，然后在DB1服务器的MySQL命令行执行如下操作：
mysql>slave stop;
然后回到远程连接的MySQL数据库执行如下操作：
MySQL [(none)]> show variables like "%hostname%"; +---------------+----------------+ | Variable_name | Value | +---------------+----------------+ | hostname | DB2 | +---------------+----------------+ 1 row in set (0.01 sec) MySQL [(none)]> show variables like "%server_id%"; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | server_id | 2 | +---------------+-------+ 1 row in set (0.01 sec)
可以发现在DB1发现故障之后MySQL服务从DB1切换到了DB2服务器，至此，所有配置完成。
时间： 2024-08-07 20:18:14