MySQL Replication on CentOS 6.5 and Haproxy

MySQL 主从：

On Master server: 192.168.20.14
1. disable selinux and iptables
service iptables stop
chkconfig iptables off; chkconfig ip6tables off

setenforce 0
vi /etc/selinux/config
SELINUX=disabled

2. yum -y install mysql-server
service mysqld start; chkconfig mysqld on
mysql_secure_installation

3. vi /etc/my.cnf
[mysqld]
server-id = 1
log-bin = mysql-bin

expire_logs_days=10
max_binlog_size=100M

service mysqld restart

4. mysql -uroot -p
mysql> GRANT REPLICATION SLAVE ON *.* TO 'mysql_rep'@'%' IDENTIFIED BY 'password';
mysql> flush privileges;
mysql> FLUSH TABLES WITH READ LOCK;
mysql> show master status;

mysql> show processlist\G

mysqldump -q -u root -p --all-databases --master-data > /root/dbdump.db

mysql -uroot -p
mysql> UNLOCK TABLES;
mysql> quit;

scp /root/dbdump.db [email protected]:/root/

On Slave server: 192.168.20.15
1. disable selinux and iptables
service iptables stop
chkconfig iptables off; chkconfig ip6tables off

setenforce 0
vi /etc/selinux/config
SELINUX=disabled

2. yum -y install mysql-server
service mysqld start; chkconfig mysqld on
mysql_secure_installation

3. vi /etc/my.cnf
[mysqld]
server-id = 2

log-bin = mysql-bin

expire_logs_days=10
max_binlog_size=100M

service mysqld restart

mysql -uroot -p
mysql>stop slave;

mysql -u root -p < /root/dbdump.db

4. mysql -uroot -p
mysql> change master to master_host = '192.168.20.14',master_user = 'mysql_rep',master_password = 'password',master_log_file = 'mysql-bin.000001',master_log_pos = 106;
mysql> start slave;
mysql> show slave status\G

mysql> show processlist\G

Notes: use "show master status" on master server to get master_log_file and master_log_pos

HAproxy配置：

mysql master server: 192.168.20.14
mysql slave server: 192.168.20.15
haproxy server 1: 192.168.20.12
haproxy server 2: 192.168.20.13
haproxy VIP: 192.168.20.10

On master mysql server:
mysql -uroot -p
mysql> CREATE USER 'haproxy'@'192.168.20.12';

mysql> CREATE USER 'haproxy'@'192.168.20.13';

mysql> flush privileges;


On two haproxy server:

yum -y install mysql

vi /etc/haproxy/haproxy.cfg
defaults
#    option                  httplog
#    option http-server-close
#    option forwardfor       except 127.0.0.0/8

listen mysqld-status 192.168.20.10:3306
        balance source
        mode tcp
        option tcpka
        option mysql-check user haproxy
        server MySQL1 192.168.20.14:3306 check weight 1
        server MySQL2 192.168.20.15:3306 check backup weight 1

service haproxy reload

Testing:

On master mysql server:
mysql -uroot -p
mysql> grant all on *.* to root@'%' identified by 'password' with grant option;

from mysql client:

mysql -h 192.168.20.10 -uroot -p

On Master Server:
mysql> create database yourdb;
mysql> use yourdb;
mysql> CREATE TABLE employee (c int);
mysql> INSERT INTO employee (c) VALUES (1);
mysql> SELECT * FROM employee;

On Slave Server:
mysql> use yourdb;
mysql> SELECT * FROM employee;

主从切换：

first stop mysql service on old master

On Old Slave server: 192.168.20.15
mysql -uroot -p
mysql> stop slave;
mysql> reset master;
mysql> show master status;

cd /var/lib/mysql

rm -rf *relay*

rm -rf master.info

On Old Master server: 192.168.20.14

service mysql start
mysql -uroot -p 
mysql> stop slave;
mysql> change master to master_host = '192.168.20.15',master_user = 'mysql_rep',master_password = 'password',master_log_file = 'mysql-bin.000001',master_log_pos = 106;

mysql> start slave;
mysql> show slave status\G

1. Backup

full backup:
mysqldump -q -uroot -ppassword --flush-logs --master-data=2 --all-databases > backup.sql

incremental backup:
do changes on database
mysqladmin -uroot -ppassword flush-logs

copy the second latest mysql-bin.x to safe place

2. Restore

full restore:
mysql -uroot -ppassword < backup.sql

incremental restore:
mysqlbinlog mysql-bin.000002 mysql-bin.00000X ...(expect the latest mysql-bin.x)| mysql -uroot -ppassword

mysql -uroot -ppassword

mysql> flush privileges;