MySQL數(shù)據(jù)庫(kù)之MMM高可用群集

MMM群集架構(gòu)概述

MMM(Master-Master replication managerfor Mysql，Mysql主主復(fù)制管理器)是一套靈活的腳本程序，基于perl實(shí)現(xiàn)，用來對(duì)mysql replication進(jìn)行監(jiān)控和故障遷移，并能管理mysql Master-Master復(fù)制的配置(同一時(shí)間只有一個(gè)節(jié)點(diǎn)是可寫的)。

MMM高可用架構(gòu)說明

mmm_mond：監(jiān)控進(jìn)程，負(fù)責(zé)所有的監(jiān)控工作，決定和處理所有節(jié)點(diǎn)角色活動(dòng)。此腳本需要在監(jiān)管機(jī)上運(yùn)行。
mmm_agentd：運(yùn)行在每個(gè)mysql服務(wù)器上的代理進(jìn)程，完成監(jiān)控的探針工作和執(zhí)行簡(jiǎn)單的遠(yuǎn)端服務(wù)設(shè)置。此腳本需要在被監(jiān)管機(jī)上運(yùn)行。
mmm_control：一個(gè)簡(jiǎn)單的腳本，提供管理mmm_mond進(jìn)程的命令。
mysql-mmm的監(jiān)管端會(huì)提供多個(gè)虛擬IP（VIP），包括一個(gè)可寫VIP，多個(gè)可讀VIP，通過監(jiān)管的管理，這些IP會(huì)綁定在可用mysql之上，當(dāng)某一臺(tái)mysql宕機(jī)時(shí)，監(jiān)管會(huì)將VIP遷移至其他mysql。
在整個(gè)監(jiān)管過程中，需要在mysql中添加相關(guān)授權(quán)用戶，以便讓mysql可以支持監(jiān)理機(jī)的維護(hù)。授權(quán)的用戶包括一個(gè)mmm_monitor用戶和一個(gè)mmm_agent用戶。

MMM的優(yōu)缺點(diǎn)

優(yōu)點(diǎn)： 高可用性，擴(kuò)展性好，出現(xiàn)故障自動(dòng)切換，對(duì)于主主同步，在同一時(shí)間只提供一臺(tái)數(shù)據(jù)庫(kù)寫操作，保證的數(shù)據(jù)的一致性。
缺點(diǎn)： Monitor節(jié)點(diǎn)是單點(diǎn)，可以結(jié)合Keepalived實(shí)現(xiàn)高可用，對(duì)主機(jī)的數(shù)量有要求，需要實(shí)現(xiàn)讀寫分離，對(duì)程序來說是個(gè)挑戰(zhàn)。

實(shí)驗(yàn)環(huán)境部署

服務(wù)器角色               IP地址              代理名稱          虛擬IP

主服務(wù)器1           192.168.142.131         db1         vip192.168.142.130
(master1)

主服務(wù)器2           192.168.142.134         db2
(master2)

從服務(wù)器1           192.168.142.130         db3         vip192.168.142.251,
192.168.142.252
(slave1)    

從服務(wù)器2           192.168.142.135         db4
(slave2)    

監(jiān)控服務(wù)器           192.168.142.136 
(monitor)

第一步:在四臺(tái)服務(wù)器上都需要安裝MySQL數(shù)據(jù)庫(kù)

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(kù)
[root@localhost ~]# yum -y install mariadb-server mariadb

#關(guān)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(kù)
[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(cuò)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(jìn)制日志文件   
character_set_server=utf8               #字符集
log_bin=mysql_bin             #二進(jìn)制日志文件功能開啟
server_id=1               #不同主機(jī)id不同
log_slave_updates=true              #授權(quán)同步
sync_binlog=1               #二進(jìn)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(fù)制配置文件到其他三臺(tái)數(shù)據(jù)庫(kù)服務(wù)器,注意修改server_id

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

5.進(jìn)入數(shù)據(jù)庫(kù),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(tái)主服務(wù)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(kù)

MariaDB [(none)]> create database school;    

10.在m2上查看同步數(shù)據(jù)庫(kù)

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

11.在兩臺(tái)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(wù)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(tái)服務(wù)器上安裝MMM相關(guān)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(tái)服務(wù)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(shè)定主服務(wù)器虛擬IP
<role writer>
    hosts   db1, db2
    ips     192.168.142.250
    mode    exclusive
</role>

#設(shè)定從服務(wù)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(fù)制配置文件到其他三臺(tái)服務(wù)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(wù)器

1.安裝epel-release源以及MMM相關(guān)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(fù)制配置文件到監(jiān)控服務(wù)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(tái)服務(wù)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(kù)服務(wù)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(kù)服務(wù)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(kù)

MariaDB [(none)]> flush privileges;
Query OK, 0 rows affected (0.02 sec)

7.在所有數(shù)據(jù)庫(kù)服務(wù)器上設(shè)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(rèn)名稱
this db1 

#m2中名稱
this db2

#s1中名稱
this db3

#s2中名稱
this db4

8.所有數(shù)據(jù)庫(kù)服務(wù)器上啟動(dòng)代理功能并設(shè)定開機(jī)自啟動(dòng)

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

#設(shè)置開機(jī)自啟動(dòng)
[root@localhost ~]# systemctl enable mysql-mmm-agent.service   

9.在monitor服務(wù)器開啟監(jiān)控服務(wù)

[root@localhost mysql-mmm]# systemctl start mysql-mmm-monitor.service 

10.查看各節(jié)點(diǎn)的情況

[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)

11.檢測(cè)所有服務(wù)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

第三步:故障測(cè)試

1.模擬m1服務(wù)器宕機(jī),停止服務(wù)

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

2.當(dāng)m1服務(wù)器宕機(jī)后,m2接收虛擬IP繼續(xù)提供服務(wù)

[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.模擬s1服務(wù)器宕機(jī),停止服務(wù)

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

4.當(dāng)s1服務(wù)器宕機(jī)后,s2接收虛擬IP繼續(xù)提供服務(wù)

[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

5.在m1服務(wù)器上為監(jiān)控服務(wù)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)

6.在監(jiān)控服務(wù)器上安裝數(shù)據(jù)庫(kù)客戶端

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

7.在監(jiān)控服務(wù)器上使用指定用戶登錄數(shù)據(jù)庫(kù),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(gè)數(shù)據(jù)庫(kù)
MariaDB [(none)]> create database BDQN;
Query OK, 1 row affected (0.01 sec)

8.在所有數(shù)據(jù)庫(kù)上都能查看及時(shí)同步到的數(shù)據(jù)信息

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