马哥Linux第十五周

Q1、编写脚本，支持让用户自主选择，使用mysqldump还是xtraback全量备份。

vim mysql_full_backup.sh
#!/bin/bash
echo "Please choose database backup mode"
echo "1) mysqldump"
echo "2) xtrabackup"
echo
read -p "which your choose: " MODE
read -p "Please input backup directory:" DIR

if [ "$MODE" == "1" ];then
    [ -d $DIR ] || mkdir $DIR
    rpm -q mariadb &> /dev/null || yum install mariadb -y > /dev/null
    BACKUP_TIME=`date +%Y-%m-%d_%H%M%S`
    mysqldump -uroot -A -F -E -R --single-transaction --master-data=1 --flush-privileges --triggers --default-character-set=utf8 --hex-blob > $DIR/fullbak_${BACKUP_TIME}.sql
    [ `echo $?` ] && echo;echo "Backup path: $DIR/fullbak_${BACKUP_TIME}.sql";echo "Backup Complete"!!!
elif [ "$MODE" == "2" ];then
    [ -d $DIR ] || mkdir $DIR
    rpm -q percona-xtrabackup &> /dev/null || yum install percona-xtrabackup -y > /dev/null
    xtrabackup --backup --target-dir=$DIR &> /dev/null
    [ `echo $?` ] && echo;echo "Backup path: $DIR";echo "Backup Complete"!!!
else
    echo
    echo "choose mode error"
    exit 5
fi

Q2、配置Mysql主从同步

#master
[root@rs1 ~]# yum install mariadb-server -y
[root@rs1 ~]# vim /etc/my.cnf
[mysqld]
server_id=27
log_bin
skip_name_resolve
binlog_format=row
[root@rs1 ~]# systemctl start mariadb
[root@rs1 ~]# mysql -e "grant replication slave on *.* to repluser@'192.168.37.%' identified by 'centos'"
[root@rs1 ~]# mysql -e "flush privileges"
[root@rs1 ~]# mysqldump -A -F -E -R --single-transaction --master-data=1 --flush-privileges --triggers --hex-blob > /data/mysql/master_all.sql
scp /data/mysql/master_all.sql root@192.168.37.37:/data
[root@rs1 ~]# mysql 
MariaDB [(none)]> show master logs;
+--------------------+-----------+
| Log_name           | File_size |
+--------------------+-----------+
| mariadb-bin.000001 |       520 |
| mariadb-bin.000002 |       245 |
+--------------------+-----------+
2 rows in set (0.00 sec)

#slave
[root@rs2 ~]# yum install mariadb-server -y
[root@rs2 ~]# vim /etc/my.cnf
[mysqld]
server-id=37
log-bin
read-only
skip_name_resolve
binlog_format=row
[root@rs2 ~]# vim /data/master_all.sql
CHANGE MASTER TO 
MASTER_HOST='192.168.37.27',
MASTER_USER='repluser',
MASTER_PASSWORD='centos',
MASTER_PORT=3306,
MASTER_LOG_FILE='mariadb-bin.000002', MASTER_LOG_POS=245;
[root@rs2 ~]# systemctl start mariadb
[root@rs2 ~]# mysql 
MariaDB [none]> stop slave;
MariaDB [none]> source /data/master_all.sql
MariaDB [none]> start slave;
MariaDB [none]> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.37.27
                  Master_User: repluser
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mariadb-bin.000002
          Read_Master_Log_Pos: 245
               Relay_Log_File: mariadb-relay-bin.000002
                Relay_Log_Pos: 531
        Relay_Master_Log_File: mariadb-bin.000002
             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: 245
              Relay_Log_Space: 827
              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: 27
1 row in set (0.00 sec)

#测试主从同步
#master上创建数据库
MariaDB [(none)]> create database magedu;
Query OK, 1 row affected (0.00 sec)
#slave上查看
ariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| hellodb            |
| magedu             |
| mysql              |
| performance_schema |
| test               |
+--------------------+
6 rows in set (0.00 sec)

Q3、使用MHA实现Mysql高可用

#环境：4台机器
#mha-master,mysql-master,mysql-slave1,mysql-slave2

首先：四台机器都装上mysql
yum install mariadb-server -y

#mysql-master
[root@mysql-master ~]# vim /etc/my.cnf
[mysqld]
server_id=17
log_bin
binlog_format=row
skip_name_resolve
[root@mysql-master ~]# systemctl start mariadb
[root@mysql-master ~]# mysql -e "grant replication slave on *.* to repluser@'192.168.37.%' identified by 'magedu'" 
[root@mysql-master ~]# mysql -e  "grant all on *.* to mhauser@'192.168.37.%' identified by 'magedu'"
[root@mysql-master ~]# mysql -e "flush privileges"
[root@mysql-master ~]# mysql -e "show master status"
+--------------------+----------+--------------+------------------+
| File               | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+--------------------+----------+--------------+------------------+
| mariadb-bin.000001 |      475 |              |                  |
+--------------------+----------+--------------+------------------+
[root@mysql-master ~]# yum install mha4mysql-node-0.56-0.el6.noarch.rpm -y  

#slave1
[root@rs1 ~]# vim /etc/my.cnf
[mysqld]
skip_name_resolve
server_id=27
log_bin
binlog_format=row
read-only
relay_log_purge=0
[root@rs1 ~]# systemctl start mariadb
[root@rs1 ~]# mysql

MariaDB [(none)]> CHANGE MASTER TO MASTER_HOST='192.168.37.17',
    -> MASTER_USER='repluser', MASTER_PASSWORD='magedu',
    -> MASTER_LOG_FILE='mariadb-bin.000001', MASTER_LOG_POS=245;
Query OK, 0 rows affected (0.01 sec)

MariaDB [(none)]> start slave;
Query OK, 0 rows affected (0.00 sec)
[root@rs1 ~]# yum install mha4mysql-node-0.56-0.el6.noarch.rpm -y

#slave2
[root@rs2 ~]# vim /etc/my.cnf
[mysqld]
skip_name_resolve
server_id=37
log_bin
binlog_format=row
read-only
relay_log_purge=0
[root@rs2 ~]# systemctl start mariadb
[root@rs2 ~]# mysql

MariaDB [(none)]> CHANGE MASTER TO MASTER_HOST='192.168.37.17',
    -> MASTER_USER='repluser', MASTER_PASSWORD='magedu',
    -> MASTER_LOG_FILE='mariadb-bin.000001', MASTER_LOG_POS=245;
Query OK, 0 rows affected (0.01 sec)

MariaDB [(none)]> start slave;
Query OK, 0 rows affected (0.00 sec)
[root@rs2 ~]# yum install mha4mysql-node-0.56-0.el6.noarch.rpm -y

#mha-master
[root@mha ~]# yum install mha4mysql-manager-0.56-0.el6.noarch.rpm mha4mysql-node-0.56-0.el6.noarch.rpm -y   #需要epel源
[root@mha ~]# ssh-keygen
[root@mha ~]# ssh-copy-id 192.168.37.7
[root@mha ~]# scp -r .ssh/ 192.168.37.17:/root/
[root@mha ~]# scp -r .ssh/ 192.168.37.27:/root/
[root@mha ~]# scp -r .ssh/ 192.168.37.37:/root/
[root@mha ~]# mkdir /etc/mha
[root@mha ~]# vim /etc/mha/app1.cnf
[root@mha-master ~]# vim /etc/mha/app1.cnf
[server default]
  user=mhauser
  password=magedu
  manager_workdir=/data/mastermha/app1/
  manager_log=/data/mastermha/app1/manager.log
  remote_workdir=/data/mastermha/app1/
  ssh_user=root
  repl_user=repluser
  repl_password=magedu
  ping_interval=1
[server1]
  hostname=192.168.37.17
  candidate_master=1
[server2]
  hostname=192.168.37.27
  candidate_master=1
[server3]
  hostname=192.168.37.37
  candidate_master=1
[root@mha ~]# masterha_check_ssh --conf=/etc/mha/app1.cnf       #检查ssh连接
[root@mha ~]# masterha_check_repl --conf=/etc/mha/app1.cnf      #检查同步状况

#在前台启动，一次性的，发生故障后把从变主后任务就结束了
[root@mha ~]# masterha_manager --conf=/etc/mha/app1.cnf         #启动服务

image.png

此时断电mysql-master,可以看到任务已停止

image.png

查看日志可以看到27变为主了
[root@mha ~]# tail /data/mastermha/app1/manager.log

image.png