MySQL數(shù)據(jù)庫——MMM高可用群集架構(gòu)

概念

MMM(Master-Master replication managerfor Mysql，Mysql主主復制管理器)是一套靈活的腳本程序，基于perl實現(xiàn)，
用來對mysql replication進行監(jiān)控和故障遷移，并能管理mysql Master-Master復制的配置(同一時間只有一個節(jié)點是可寫的)。

MMM高可用架構(gòu)說明

mmm_mond：監(jiān)控進程，負責所有的監(jiān)控工作，決定和處理所有節(jié)點角色活動。此腳本需要在監(jiān)管機上運行。
mmm_agentd：運行在每個mysql服務器上的代理進程，完成監(jiān)控的探針工作和執(zhí)行簡單的遠端服務設置。此腳本需要在被監(jiān)管機上運行。
mmm_control：一個簡單的腳本，提供管理mmm_mond進程的命令。
mysql-mmm的監(jiān)管端會提供多個虛擬IP（VIP），包括一個可寫VIP，多個可讀VIP，通過監(jiān)管的管理，這些IP會綁定在可用mysql之上，當某一臺mysql宕機時，監(jiān)管會將VIP遷移至其他mysql。
    在整個監(jiān)管過程中，需要在mysql中添加相關授權(quán)用戶，以便讓mysql可以支持監(jiān)理機的維護。授權(quán)的用戶包括一個mmm_monitor用戶和一個mmm_agent用戶。

MMM的優(yōu)缺點

優(yōu)點： 高可用性，擴展性好，出現(xiàn)故障自動切換，對于主主同步，在同一時間只提供一臺數(shù)據(jù)庫寫操作，保證的數(shù)據(jù)的一致性。
缺點： Monitor節(jié)點是單點，可以結(jié)合Keepalived實現(xiàn)高可用，對主機的數(shù)量有要求，需要實現(xiàn)讀寫分離，對程序來說是個挑戰(zhàn)。

實驗環(huán)境部署

第一步:在四臺服務器上都需要安裝MySQL數(shù)據(jù)庫

1.配置ALI云源，然后安裝epel-release源

[root@localhost ~]# wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

[root@localhost ~]# yum -y install epel-release

[root@localhost ~]# yum clean all && yum makecache

2.搭建本地yum源

#安裝數(shù)據(jù)庫
[root@localhost ~]# yum -y install mariadb-server mariadb

#關閉防火墻和安全功能
[root@localhost ~]# systemctl stop firewalld.service 
[root@localhost ~]# setenforce 0

#開啟數(shù)據(jù)庫
[root@localhost ~]# systemctl start mariadb.service

3.修改ml主配置文件

[root@localhost ~]# vim /etc/my.cnf
#刪除前9行，添加以下內(nèi)容
[mysqld]
log_error=/var/lib/mysql/mysql.err          #錯誤日志的文件位置
log=/var/lib/mysql/mysql_log.log            #訪問日志的文件位置
log_slow_queries=/var/lib/mysql_slow_queris.log         #man日志的文件位置
binlog-ignore-db=mysql,information_schema          #mysql,information_schema不生成二進制日志文件   
character_set_server=utf8               #字符集
log_bin=mysql_bin             #二進制日志文件功能開啟
server_id=1               #不同主機id不同
log_slave_updates=true              #授權(quán)同步
sync_binlog=1               #二進制日志文件功能開啟
auto_increment_increment=2              #自增量
auto_increment_offset=1                 #起始值

[root@localhost ~]# systemctl restart mariadb.service 
[root@localhost ~]# netstat -natp | grep 3306

4.復制配置文件到其他三臺數(shù)據(jù)庫服務器,注意修改server_id

[root@localhost ~]# scp /etc/my.cnf root@192.168.142.134:etc/

5.進入數(shù)據(jù)庫,并查看日志文件信息

[root@localhost ~]# mysql

#查看記錄日志文件名稱和位置值
MariaDB [(none)]> show master status;       
+------------------+----------+--------------+--------------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB         |
+------------------+----------+--------------+--------------------------+
| mysql_bin.000001 |       245|              | mysql,information_schema |
+------------------+----------+--------------+--------------------------+
1 row in set (0.00 sec)

6.在m1和m2上互相授予訪問的權(quán)限,并授權(quán)同步日志

#在m1和m2上互相授予訪問的權(quán)限
MariaDB [(none)]> grant replication slave on *.* to 'replication'@'192.168.142.%' identified by '123456';

#在m1上指定m2的日志文件名和位置參數(shù)
MariaDB [(none)]> change master to master_host='192.168.142.134',master_user='replication',master_password='123456',master_log_file='mysql_bin.000001',master_log_pos=245;

#在m2上指定m1的日志文件名和位置參數(shù)
MariaDB [(none)]> change master to master_host='192.168.142.131',master_user='replication',master_password='123456',master_log_file='mysql_bin.000001',master_log_pos=245;

7.在m1上開啟同步功能

MariaDB [(none)]> start slave;

8.查看同步狀態(tài),兩臺主服務器都要看到Y(jié)es

MariaDB [(none)]> show slave status\G;

             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes

9.在m1上創(chuàng)建數(shù)據(jù)庫

MariaDB [(none)]> create database school; 

10.在m2上查看同步數(shù)據(jù)庫

MariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| school             |
| test               |
+--------------------+
5 rows in set (0.00 sec)

11.在兩臺從上做-注意日志文件和位置參數(shù)的改變（都指向m1)

MariaDB [(none)]> change master to master_host='192.168.142.131',master_user='replication',master_password='123456',master_log_file='mysql_bin.000001',master_log_pos=245;

12.開啟同步功能

MariaDB [(none)]> start slave;

#在從服務器上查看同步數(shù)據(jù)信息
MariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| school             |
| test               |
+--------------------+
5 rows in set (0.00 sec)

13.在四臺服務器上安裝MMM相關軟件

[root@localhost ~]# yum -y install mysql-mmm*

14.配置mmm_common.conf配置文件

[root@localhost ~]# vim /etc/mysql-mmm/mmm_common.conf

<host default>
#修改網(wǎng)卡為ens33
    cluster_interface       ens33
    pid_path                /run/mysql-mmm-agent.pid
    bin_path                /usr/libexec/mysql-mmm/
    replication_user        replicantion

    #修改授權(quán)密碼
    replication_password    123456
    agent_user              mmm_agent

    #修改代理授權(quán)密碼
    agent_password          123456
</host>

#指定四臺服務器的角色與IP地址
<host db1>
    ip      192.168.142.131
    mode    master
    peer    db2
</host>

<host db2>
    ip      192.168.142.134
    mode    master
    peer    db1
</host>

<host db3>
    ip      192.168.142.130
    mode    slave
</host>

<host db4>
    ip      192.168.142.135
    mode    slave
</host>

#設定主服務器虛擬IP
<role writer>
    hosts   db1, db2
    ips     192.168.142.250
    mode    exclusive
</role>

#設定從服務器虛擬IP
<role reader>
    hosts   db3, db4
    ips     192.168.142.251, 192.168.142.252
    mode    balanced
</role>

15.從m1上面復制配置文件到其他三臺服務器

[root@localhost ~]# scp mmm_common.conf/mmm_common.conf root@192.168.142.134:/etc/mysql-mmm/mmm_common.conf
[root@localhost ~]# scp mmm_common.conf/mmm_common.conf root@192.168.142.130:/etc/mysql-mmm/mmm_common.conf
[root@localhost ~]# scp mmm_common.conf/mmm_common.conf root@192.168.142.135:/etc/mysql-mmm/mmm_common.conf

第二步:配置monitor監(jiān)控服務器

1.安裝epel-release源以及MMM相關軟件

[root@localhost ~]# systemctl stop firewalld.service 
[root@localhost ~]# setenforce 0
[root@localhost ~]# wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
[root@localhost ~]# yum -y install epel-release
[root@localhost ~]# yum clean all && yum makecache
[root@localhost ~]# yum -y install mysql-mmm*

2.從m1上面復制配置文件到監(jiān)控服務器

[root@localhost ~]# scp mmm_common.conf root@192.168.142.134:/etc/mysql-mmm/

3.配置mmm_common.conf配置文件

[root@localhost ~]# vim /etc/mysql-mmm/mmm_mon.conf

<monitor>
    ip                  127.0.0.1
    pid_path            /run/mysql-mmm-monitor.pid
    bin_path            /usr/libexec/mysql-mmm
    status_path         /var/lib/mysql-mmm/mmm_mond.status

    #指向四臺服務器的IP地址
    ping_ips            192.168.142.131,192.168.142.134,192.168.142.130,192.168.142.135
    auto_set_online     10

4.在所有數(shù)據(jù)庫服務器上為mmm_agent授權(quán)

MariaDB [(none)]> grant super, replication client, process on *.* to 'mmm_agent'@'192.168.142.%' identified by '123456';
Query OK, 0 rows affected (0.02 sec)

5.在所有數(shù)據(jù)庫服務器上為mmm_moniter授權(quán)

MariaDB [(none)]> grant replication client on *.* to 'mmm_monitor'@'192.168.18.%' identified by '123456'; 
Query OK, 0 rows affected (0.02 sec)

6.刷新數(shù)據(jù)庫、在所有數(shù)據(jù)庫服務器上設定代理名稱

[root@localhost ~]# vim /etc/mysql-mmm/mmm_agent.conf   #修改代理配置文件
#m1中默認名稱
this db1 

#m2中名稱
this db2

#s1中名稱
this db3

#s2中名稱
this db4

7.所有數(shù)據(jù)庫服務器上啟動代理功能并設定開機自啟動

#啟動代理功能
[root@localhost ~]# systemctl start mysql-mmm-agent.service

#設置開機自啟動
[root@localhost ~]# systemctl enable mysql-mmm-agent.service   

8.在monitor服務器開啟監(jiān)控服務、查看各節(jié)點的情況

[root@localhost mysql-mmm]# systemctl start mysql-mmm-monitor.service 
[root@localhost ~]# mmm_control show
  db1(192.168.142.131) master/ONLINE. Roles: writer(192.168.142.250)
  db2(192.168.142.134) master/ONLINE. Roles: 
  db3(192.168.142.130) slave/ONLINE. Roles: reader(192.168.142.252)
  db4(192.168.142.135) slave/ONLINE. Roles: reader(192.168.142.251)

9、檢測所有服務器狀態(tài)

[root@localhost ~]# mmm_control checks all
db4  ping         [last change: 2019/11/25 18:23:03]  OK
db4  mysql        [last change: 2019/11/25 18:23:03]  OK
db4  rep_threads  [last change: 2019/11/25 18:23:03]  OK
db4  rep_backlog  [last change: 2019/11/25 18:23:03]  OK: Backlog is null
db2  ping         [last change: 2019/11/25 18:23:03]  OK
db2  mysql        [last change: 2019/11/25 18:59:01]  OK
db2  rep_threads  [last change: 2019/11/25 18:59:01]  OK
db2  rep_backlog  [last change: 2019/11/25 18:59:01]  OK: Backlog is null
db3  ping         [last change: 2019/11/25 18:23:03]  OK
db3  mysql        [last change: 2019/11/25 18:59:01]  OK
db3  rep_threads  [last change: 2019/11/25 18:59:01]  OK
db3  rep_backlog  [last change: 2019/11/25 18:59:01]  OK: Backlog is null
db1  ping         [last change: 2019/11/25 18:23:03]  OK
db1  mysql        [last change: 2019/11/25 18:59:01]  OK
db1  rep_threads  [last change: 2019/11/25 18:59:01]  OK
db1  rep_backlog  [last change: 2019/11/25 18:59:01]  OK: Backlog is null

第三、故障測試

1、模擬m1服務器宕機,停止服務

[root@localhost ~]# systemctl stop mariadb.service

2.當m1服務器宕機后,m2接收虛擬IP繼續(xù)提供服務

[root@localhost ~]# mmm_control show
  db1(192.168.142.131) master/ONLINE. Roles: 
  db2(192.168.142.134) master/ONLINE. Roles: writer(192.168.142.250)
  db3(192.168.142.130) slave/ONLINE. Roles: reader(192.168.142.252)
  db4(192.168.142.135) slave/ONLINE. Roles: reader(192.168.142.251)

3.當s1服務器宕機后,s2接收虛擬IP繼續(xù)提供服務

[root@localhost ~]# mmm_control show db1(192.168.142.131) master/ONLINE. Roles: writer(192.168.142.250) 
db2(192.168.142.134) master/ONLINE. Roles: 
db3(192.168.142.130) slave/HARD_OFFLINE. Roles: 
db4(192.168.142.135) slave/ONLINE. Roles: reader(192.168.142.251), reader(192.168.142.252

4.在m1服務器上為監(jiān)控服務器地址授權(quán)登錄

MariaDB [(none)]> grant all on *.* to 'root'@'192.168.142.136' identified by '123456';
Query OK, 0 rows affected (0.00 sec)

5.在監(jiān)控服務器上安裝數(shù)據(jù)庫客戶端

[root@localhost ~]# yum -y install mariadb 

6.在監(jiān)控服務器上使用指定用戶登錄數(shù)據(jù)庫,并創(chuàng)建數(shù)據(jù)信息

[root@localhost ~]# mysql -u root -p -h 192.168.142.250
Enter password: 
#輸入密碼即可

#創(chuàng)建一個數(shù)據(jù)庫
MariaDB [(none)]> create database BDQN;
Query OK, 1 row affected (0.01 sec)

7.在所有數(shù)據(jù)庫上都能查看及時同步到的數(shù)據(jù)信息

MariaDB [(none)]> show databases;   #查看數(shù)據(jù)庫
+--------------------+
| Database           |
+--------------------+
| information_schema |
| BDQN               |          #同步到的BDQN數(shù)據(jù)庫
| mysql              |
| performance_schema |
| school             |
| test               |
+--------------------+
6 rows in set (0.00 sec)

到此MMM群集架構(gòu)已完成,謝謝閱讀!!!