ProxySQL+MGR實現讀寫分離和主節點故障無感知切換 - 完整操作記錄

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前面的文章介紹了ProxySQL用法，這里說下ProxySQL中間件針對Mysql組復制模式實現讀寫分離以及主節點故障時能夠自動切換到新的主節點，而應用對此過程無感知的功能。Mysql組復制(MGR)組復制能夠完成主節點故障后推選出來新的主節點，不過在應用層不可能通過修改新的主節點的IP來連接新的主節點，但是通過MGR+ProxySQL可以實際主節點故障時應用無感應自動切換到新的主節點。

根據上圖，描述下實現思路：三個節點使multi-primary的方式連接，應用通過連接ProxySQL中間件，根據sql的屬性（是否為select語句）來決定連接哪一個節點，一個可寫節點，兩個只讀節點（其實三個都是可寫節點，只不過通過proxysql進行了讀寫分離）。如果默認的可寫節點掛掉的話，proxysql通過定期運行的調度器會將另一個只讀節點的其中一臺設為可寫節點，實際主節點故障應用無感應的要求。上述的整個過程中，應用無需任何變動。應用從意識發生了故障，到連接重新指向新的主，正常提供服務，秒級別的間隔。

一、環境準備

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172.16.60.211?????? MGR-node1 (master1)???? Centos7.5 172.16.60.212?????? MGR-node2 (master2)???? Centos7.5 172.16.60.213?????? MGR-node3 (master3)???? Centos7.5 172.16.60.214?????? ProxySQL-node?????????? Centos7.5 [root@MGR-node1 ~] # cat /etc/redhat-release CentOS Linux release 7.5.1804 (Core) ???? 為了方便實驗，關閉所有節點的防火墻 [root@MGR-node1 ~] # systemctl stop firewalld [root@MGR-node1 ~] # firewall-cmd --state not running ???? [root@MGR-node1 ~] # cat /etc/sysconfig/selinux |grep "SELINUX=disabled" SELINUX=disabled [root@MGR-node1 ~] # setenforce 0??????????? setenforce: SELinux is disabled [root@MGR-node1 ~] # getenforce????????????? Disabled ?? 特別要注意一個關鍵點: 必須設置好各個mysql節點的主機名，并且保證能通過主機名找到各成員！ 則必須要在每個節點的 /etc/hosts 里面做主機名綁定，否則后續將節點加入group組會失敗！報錯RECOVERING！！ [root@MGR-node1 ~] # cat /etc/hosts ........ 172.16.60.211??? MGR-node1 172.16.60.212??? MGR-node2 172.16.60.213??? MGR-node3

二、在三個節點上安裝Mysql5.7

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在三個mysql節點機上使用yum方式安裝Mysql5.7，參考：https: //www .cnblogs.com /kevingrace/p/8340690 .html ???? 安裝MySQL yum資源庫 [root@MGR-node1 ~] # yum localinstall https://dev.mysql.com/get/mysql57-community-release-el7-8.noarch.rpm ???? 安裝MySQL 5.7 [root@MGR-node1 ~] # yum install -y mysql-community-server ???? 啟動MySQL服務器和MySQL的自動啟動 [root@MGR-node1 ~] # systemctl start mysqld.service [root@MGR-node1 ~] # systemctl enable mysqld.service ???? 設置登錄密碼 由于MySQL從5.7開始不允許首次安裝后使用空密碼進行登錄！為了加強安全性，系統會隨機生成一個密碼以供管理員首次登錄使用， 這個密碼記錄在 /var/log/mysqld .log文件中，使用下面的命令可以查看此密碼： [root@MGR-node1 ~] # cat /var/log/mysqld.log|grep 'A temporary password' 2019-01-11T05:53:17.824073Z 1 [Note] A temporary password is generated for root@localhost: TaN.k:*Qw2xs ???? 使用上面查看的密碼TaN.k:*Qw2xs 登錄mysql，并重置密碼為123456 [root@MGR-node1 ~] # mysql -p???????????????? #輸入默認的密碼：TaN.k:*Qw2xs ............. mysql> set global validate_password_policy=0; Query OK, 0 rows affected (0.00 sec) ???? mysql> set global validate_password_length=1; Query OK, 0 rows affected (0.00 sec) ???? mysql> set password=password( "123456" ); Query OK, 0 rows affected, 1 warning (0.00 sec) ???? mysql> flush privileges; Query OK, 0 rows affected (0.00 sec) ???? 查看mysql版本 [root@MGR-node1 ~] # mysql -p123456 ........ mysql> select version(); +-----------+ | version() | +-----------+ | 5.7.24??? | +-----------+ 1 row in set (0.00 sec) ??? ===================================================================== 溫馨提示 mysql5.7通過上面默認安裝后，執行語句可能會報錯： ERROR 1819 (HY000): Your password does not satisfy the current policy requirements ??? 這個報錯與Mysql 密碼安全策略validate_password_policy的值有關，validate_password_policy可以取0、1、2三個值： 解決辦法： set global validate_password_policy=0; set global validate_password_length=1;

三、MGR組復制環境部署 (多寫模式)

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可以參考：https: //www .cnblogs.com /kevingrace/p/10260685 .html 由于之前做了其他測試，這里需要將三個節點的mysql環境抹干凈： # systemctl? stop? mysqld # rm -rf /var/lib/mysql # systemctl start mysqld 然后重啟密碼 # cat /var/log/mysqld.log|grep 'A temporary password' # mysql -p123456 mysql> set global validate_password_policy=0; mysql> set global validate_password_length=1; mysql> set password=password( "123456" ); mysql> flush privileges; ======================================================= 1） MGR-node1節點操作 [root@MGR-node1 ~] # mysql -p123456 ......... mysql> select uuid(); +--------------------------------------+ | uuid()?????????????????????????????? | +--------------------------------------+ | ae09faae-34bb-11e9-9f91-005056ac6820 | +--------------------------------------+ 1 row in set (0.00 sec) [root@MGR-node1 ~] # cp /etc/my.cnf /etc/my.cnf.bak [root@MGR-node1 ~] # >/etc/my.cnf [root@MGR-node1 ~] # vim /etc/my.cnf [mysqld] datadir = /var/lib/mysql socket = /var/lib/mysql/mysql .sock ???????? symbolic-links = 0 ???????? log-error = /var/log/mysqld .log pid- file = /var/run/mysqld/mysqld .pid ???? #GTID: server_id = 1 gtid_mode = on enforce_gtid_consistency = on ???? master_info_repository=TABLE relay_log_info_repository=TABLE binlog_checksum=NONE ???????? #binlog log_bin = mysql-bin log-slave-updates = 1 binlog_format = row sync -master-info = 1 sync_binlog = 1 ??????? #relay log skip_slave_start = 1 ???? transaction_write_set_extraction=XXHASH64????? loose-group_replication_group_name= "5db40c3c-180c-11e9-afbf-005056ac6820"???? loose-group_replication_start_on_boot=off??? loose-group_replication_local_address= "172.16.60.211:24901" loose-group_replication_group_seeds= "172.16.60.211:24901,172.16.60.212:24901,172.16.60.213:24901" loose-group_replication_bootstrap_group=off loose-group_replication_single_primary_mode=off????? loose-group_replication_enforce_update_everywhere_checks=on??? loose-group_replication_ip_whitelist= "172.16.60.0/24,127.0.0.1/8"?? 重啟mysql服務 [root@MGR-node1 ~] # systemctl restart mysqld 登錄mysql進行相關設置操作 [root@MGR-node1 ~] # mysql -p123456 ............ mysql> SET SQL_LOG_BIN=0;? Query OK, 0 rows affected (0.00 sec) mysql> GRANT REPLICATION SLAVE ON *.* TO rpl_slave@ '%' IDENTIFIED BY 'slave@123' ; Query OK, 0 rows affected, 1 warning (0.00 sec) mysql> FLUSH PRIVILEGES; Query OK, 0 rows affected (0.01 sec) mysql> reset master; Query OK, 0 rows affected (0.19 sec) mysql> SET SQL_LOG_BIN=1; Query OK, 0 rows affected (0.00 sec) mysql> CHANGE MASTER TO MASTER_USER= 'rpl_slave' , MASTER_PASSWORD= 'slave@123' FOR CHANNEL 'group_replication_recovery' ; Query OK, 0 rows affected, 2 warnings (0.33 sec) mysql> INSTALL PLUGIN group_replication SONAME 'group_replication.so' ; Query OK, 0 rows affected (0.03 sec) mysql> SHOW PLUGINS; +----------------------------+----------+--------------------+----------------------+---------+ | Name?????????????????????? | Status?? | Type?????????????? | Library????????????? | License | +----------------------------+----------+--------------------+----------------------+---------+ ............... ............... | group_replication????????? | ACTIVE?? | GROUP REPLICATION? | group_replication.so | GPL???? | +----------------------------+----------+--------------------+----------------------+---------+ 46 rows in set (0.00 sec) mysql> SET GLOBAL group_replication_bootstrap_group=ON; Query OK, 0 rows affected (0.00 sec) mysql> START GROUP_REPLICATION; Query OK, 0 rows affected (2.34 sec) mysql> SET GLOBAL group_replication_bootstrap_group=OFF; Query OK, 0 rows affected (0.00 sec) mysql> SELECT * FROM performance_schema.replication_group_members; +---------------------------+--------------------------------------+-------------+-------------+--------------+ | CHANNEL_NAME????????????? | MEMBER_ID??????????????????????????? | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE | +---------------------------+--------------------------------------+-------------+-------------+--------------+ | group_replication_applier | 42ca8591-34bb-11e9-8296-005056ac6820 | MGR-node1?? |??????? 3306 | ONLINE?????? | +---------------------------+--------------------------------------+-------------+-------------+--------------+ 1 row in set (0.00 sec) 比如要保證上面的group_replication_applier的狀態為 "ONLINE" 才對！ ?? 創建一個測試庫 mysql> CREATE DATABASE kevin CHARACTER SET utf8 COLLATE utf8_general_ci;????? Query OK, 1 row affected (0.03 sec) ?? mysql> use kevin; Database changed mysql> create table if not exists haha ( id int(10) PRIMARY KEY AUTO_INCREMENT,name varchar(50) NOT NULL); Query OK, 0 rows affected (0.24 sec) ?? mysql> insert into kevin.haha values(1, "wangshibo" ),(2, "guohuihui" ),(3, "yangyang" ),(4, "shikui" );????? Query OK, 4 rows affected (0.07 sec) Records: 4? Duplicates: 0? Warnings: 0 ?? mysql> select * from kevin.haha; +----+-----------+ | id | name????? | +----+-----------+ |? 1 | wangshibo | |? 2 | guohuihui | |? 3 | yangyang? | |? 4 | shikui??? | +----+-----------+ 4 rows in set (0.00 sec) ===================================================================== 2） MGR-node2節點操作 [root@MGR-node2 ~] # cp /etc/my.cnf /etc/my.cnf.bak [root@MGR-node2 ~] # >/etc/my.cnf [root@MGR-node2 ~] # vim /etc/my.cnf [mysqld] datadir = /var/lib/mysql socket = /var/lib/mysql/mysql .sock ?????? symbolic-links = 0 ?????? log-error = /var/log/mysqld .log pid- file = /var/run/mysqld/mysqld .pid ?? #GTID: server_id = 2 gtid_mode = on enforce_gtid_consistency = on ?? master_info_repository=TABLE relay_log_info_repository=TABLE binlog_checksum=NONE ?????? #binlog log_bin = mysql-bin log-slave-updates = 1 binlog_format = row sync -master-info = 1 sync_binlog = 1 ????? #relay log skip_slave_start = 1 ?? transaction_write_set_extraction=XXHASH64 loose-group_replication_group_name= "5db40c3c-180c-11e9-afbf-005056ac6820" loose-group_replication_start_on_boot=off loose-group_replication_local_address= "172.16.60.212:24901" loose-group_replication_group_seeds= "172.16.60.211:24901,172.16.60.212:24901,172.16.60.213:24901" loose-group_replication_bootstrap_group=off loose-group_replication_single_primary_mode=off loose-group_replication_enforce_update_everywhere_checks=on loose-group_replication_ip_whitelist= "172.16.60.0/24,127.0.0.1/8" 重啟mysql服務 [root@MGR-node2 ~] # systemctl restart mysqld 登錄mysql進行相關設置操作 [root@MGR-node2 ~] # mysql -p123456 ......... mysql> SET SQL_LOG_BIN=0; Query OK, 0 rows affected (0.00 sec) mysql> GRANT REPLICATION SLAVE ON *.* TO rpl_slave@ '%' IDENTIFIED BY 'slave@123' ; Query OK, 0 rows affected, 1 warning (0.00 sec) mysql> FLUSH PRIVILEGES; Query OK, 0 rows affected (0.00 sec) mysql> reset master; Query OK, 0 rows affected (0.17 sec) mysql> SET SQL_LOG_BIN=1; Query OK, 0 rows affected (0.00 sec) mysql> CHANGE MASTER TO MASTER_USER= 'rpl_slave' , MASTER_PASSWORD= 'slave@123' FOR CHANNEL 'group_replication_recovery' ; Query OK, 0 rows affected, 2 warnings (0.21 sec) mysql> INSTALL PLUGIN group_replication SONAME 'group_replication.so' ; Query OK, 0 rows affected (0.20 sec) mysql> SHOW PLUGINS; +----------------------------+----------+--------------------+----------------------+---------+ | Name?????????????????????? | Status?? | Type?????????????? | Library????????????? | License | +----------------------------+----------+--------------------+----------------------+---------+ ............. ............. | group_replication????????? | ACTIVE?? | GROUP REPLICATION? | group_replication.so | GPL???? | +----------------------------+----------+--------------------+----------------------+---------+ 46 rows in set (0.00 sec) mysql> START GROUP_REPLICATION; Query OK, 0 rows affected (6.25 sec) mysql> SELECT * FROM performance_schema.replication_group_members; +---------------------------+--------------------------------------+-------------+-------------+--------------+ | CHANNEL_NAME????????????? | MEMBER_ID??????????????????????????? | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE | +---------------------------+--------------------------------------+-------------+-------------+--------------+ | group_replication_applier | 4281f7b7-34bb-11e9-8949-00505688047c | MGR-node2?? |??????? 3306 | ONLINE?????? | | group_replication_applier | 42ca8591-34bb-11e9-8296-005056ac6820 | MGR-node1?? |??????? 3306 | ONLINE?????? | +---------------------------+--------------------------------------+-------------+-------------+--------------+ 2 rows in set (0.00 sec) 查看下，發現已經將MGR-node1節點添加的數據同步過來了 mysql> show databases; +--------------------+ | Database?????????? | +--------------------+ | information_schema | | kevin????????????? | | mysql????????????? | | performance_schema | | sys??????????????? | +--------------------+ 5 rows in set (0.00 sec) mysql> select * from kevin.haha; +----+-----------+ | id | name????? | +----+-----------+ |? 1 | wangshibo | |? 2 | guohuihui | |? 3 | yangyang? | |? 4 | shikui??? | +----+-----------+ 4 rows in set (0.00 sec) ===================================================================== 3） MGR-node3節點操作 [root@MGR-node3 ~] # cp /etc/my.cnf /etc/my.cnf.bak [root@MGR-node3 ~] # >/etc/my.cnf [root@MGR-node3 ~] # vim /etc/my.cnf [mysqld] datadir = /var/lib/mysql socket = /var/lib/mysql/mysql .sock ?????? symbolic-links = 0 ?????? log-error = /var/log/mysqld .log pid- file = /var/run/mysqld/mysqld .pid ?? #GTID: server_id = 3 gtid_mode = on enforce_gtid_consistency = on ?? master_info_repository=TABLE relay_log_info_repository=TABLE binlog_checksum=NONE ?????? #binlog log_bin = mysql-bin log-slave-updates = 1 binlog_format = row sync -master-info = 1 sync_binlog = 1 ????? #relay log skip_slave_start = 1 ?? transaction_write_set_extraction=XXHASH64 loose-group_replication_group_name= "5db40c3c-180c-11e9-afbf-005056ac6820" loose-group_replication_start_on_boot=off loose-group_replication_local_address= "172.16.60.213:24901" loose-group_replication_group_seeds= "172.16.60.211:24901,172.16.60.212:24901,172.16.60.213:24901" loose-group_replication_bootstrap_group=off loose-group_replication_single_primary_mode=off loose-group_replication_enforce_update_everywhere_checks=on loose-group_replication_ip_whitelist= "172.16.60.0/24,127.0.0.1/8" 重啟mysql服務 [root@MGR-node3 ~] # systemctl restart mysqld 登錄mysql進行相關設置操作 [root@MGR-node3 ~] # mysql -p123456 .......... mysql> SET SQL_LOG_BIN=0; Query OK, 0 rows affected (0.00 sec) mysql> GRANT REPLICATION SLAVE ON *.* TO rpl_slave@ '%' IDENTIFIED BY 'slave@123' ; Query OK, 0 rows affected, 1 warning (0.00 sec) mysql> FLUSH PRIVILEGES; Query OK, 0 rows affected (0.01 sec) mysql> reset master; Query OK, 0 rows affected (0.10 sec) mysql> SET SQL_LOG_BIN=1; Query OK, 0 rows affected (0.00 sec) mysql> CHANGE MASTER TO MASTER_USER= 'rpl_slave' , MASTER_PASSWORD= 'slave@123' FOR CHANNEL 'group_replication_recovery' ; Query OK, 0 rows affected, 2 warnings (0.27 sec) mysql> INSTALL PLUGIN group_replication SONAME 'group_replication.so' ; Query OK, 0 rows affected (0.04 sec) mysql> SHOW PLUGINS; +----------------------------+----------+--------------------+----------------------+---------+ | Name?????????????????????? | Status?? | Type?????????????? | Library????????????? | License | +----------------------------+----------+--------------------+----------------------+---------+ ............. | group_replication????????? | ACTIVE?? | GROUP REPLICATION? | group_replication.so | GPL???? | +----------------------------+----------+--------------------+----------------------+---------+ 46 rows in set (0.00 sec) mysql> START GROUP_REPLICATION; Query OK, 0 rows affected (4.54 sec) mysql> SELECT * FROM performance_schema.replication_group_members; +---------------------------+--------------------------------------+-------------+-------------+--------------+ | CHANNEL_NAME????????????? | MEMBER_ID??????????????????????????? | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE | +---------------------------+--------------------------------------+-------------+-------------+--------------+ | group_replication_applier | 4281f7b7-34bb-11e9-8949-00505688047c | MGR-node2?? |??????? 3306 | ONLINE?????? | | group_replication_applier | 42ca8591-34bb-11e9-8296-005056ac6820 | MGR-node1?? |??????? 3306 | ONLINE?????? | | group_replication_applier | 456216bd-34bb-11e9-bbd1-005056880888 | MGR-node3?? |??????? 3306 | ONLINE?????? | +---------------------------+--------------------------------------+-------------+-------------+--------------+ 3 rows in set (0.00 sec) 查看下，發現已經將在其他節點上添加的數據同步過來了 mysql> show databases; +--------------------+ | Database?????????? | +--------------------+ | information_schema | | kevin????????????? | | mysql????????????? | | performance_schema | | sys??????????????? | +--------------------+ 5 rows in set (0.00 sec) mysql> select * from kevin.haha; +----+-----------+ | id | name????? | +----+-----------+ |? 1 | wangshibo | |? 2 | guohuihui | |? 3 | yangyang? | |? 4 | shikui??? | +----+-----------+ 4 rows in set (0.00 sec) ===================================================================== 4） 組復制數據同步測試 在任意一個節點上執行 mysql> SELECT * FROM performance_schema.replication_group_members; +---------------------------+--------------------------------------+-------------+-------------+--------------+ | CHANNEL_NAME????????????? | MEMBER_ID??????????????????????????? | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE | +---------------------------+--------------------------------------+-------------+-------------+--------------+ | group_replication_applier | 2658b203-1565-11e9-9f8b-005056880888 | MGR-node3?? |??????? 3306 | ONLINE?????? | | group_replication_applier | 2c1efc46-1565-11e9-ab8e-00505688047c | MGR-node2?? |??????? 3306 | ONLINE?????? | | group_replication_applier | 317e2aad-1565-11e9-9c2e-005056ac6820 | MGR-node1?? |??????? 3306 | ONLINE?????? | +---------------------------+--------------------------------------+-------------+-------------+--------------+ 3 rows in set (0.00 sec) ?? 如上，說明已經在MGR-node1、MGR-node2、MGR-node3 三個節點上成功部署了基于GTID的組復制同步環境。 現在在三個節點中的任意一個上面更新數據，那么其他兩個節點的數據庫都會將新數據同步過去的！ ?? 1）在MGR-node1節點數據庫更新數據 mysql> delete from kevin.haha where id >2; Query OK, 2 rows affected (0.14 sec) ?? 接著在MGR-node2、MGR-node3節點數據庫查看，發現更新后數據已經同步過來了！ mysql> select * from kevin.haha; +----+-----------+ | id | name????? | +----+-----------+ |? 1 | wangshibo | |? 2 | guohuihui | +----+-----------+ 2 rows in set (0.00 sec) ?? 2）在MGR-node2節點數據庫更新數據 mysql> insert into kevin.haha values(11, "beijing" ),(12, "shanghai" ),(13, "anhui" ); Query OK, 3 rows affected (0.06 sec) Records: 3? Duplicates: 0? Warnings: 0 ?? 接著在MGR-node1、MGR-node3節點數據庫查看，發現更新后數據已經同步過來了！ mysql> select * from kevin.haha; +----+-----------+ | id | name????? | +----+-----------+ |? 1 | wangshibo | |? 2 | guohuihui | | 11 | beijing?? | | 12 | shanghai? | | 13 | anhui???? | +----+-----------+ 5 rows in set (0.00 sec) ?? 3）在MGR-node3節點數據庫更新數據 mysql> update kevin.haha set id =100 where name= "anhui" ; Query OK, 1 row affected (0.16 sec) Rows matched: 1? Changed: 1? Warnings: 0 ?? mysql> delete from kevin.haha where id =12; Query OK, 1 row affected (0.22 sec) ?? 接著在MGR-node1、MGR-node2節點數據庫查看，發現更新后數據已經同步過來了！ mysql> select * from kevin.haha; +-----+-----------+ | id? | name????? | +-----+-----------+ |?? 1 | wangshibo | |?? 2 | guohuihui | |? 11 | beijing?? | | 100 | anhui???? | +-----+-----------+ 4 rows in set (0.00 sec)

四、ProxySQL讀寫分離和主節點故障無感知切換

1) 安裝mysql客戶端，用于在本機連接到ProxySQL的管理接口

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[root@ProxySQL-node ~] # vim /etc/yum.repos.d/mariadb.repo [mariadb] name = MariaDB baseurl = http: //yum .mariadb.org /10 .3.5 /centos6-amd64 gpgkey=https: //yum .mariadb.org /RPM-GPG-KEY-MariaDB gpgcheck=1 ???? 安裝mysql-clinet客戶端 [root@ProxySQL-node ~] # yum install -y MariaDB-client ??? ============================================================================ 如果遇到報錯： Error: MariaDB-compat conflicts with 1:mariadb-libs-5.5.60-1.el7_5.x86_64 ? You could try using --skip-broken to work around the problem ? You could try running: rpm -Va --nofiles --nodigest ???? 解決辦法： [root@ProxySQL-node ~] # rpm -qa|grep mariadb mariadb-libs-5.5.60-1.el7_5.x86_64 ?? [root@ProxySQL-node ~] # rpm -e mariadb-libs-5.5.60-1.el7_5.x86_64 --nodeps [root@ProxySQL-node ~] # yum install -y MariaDB-client

2) 安裝proxysql

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proxysql的rpm包下載地址: https: //pan .baidu.com /s/1S1_b5DKVCpZSOUNmtCXrrg 提取密碼: 5t1c ??? [root@ProxySQL-node ~] # yum install -y perl-DBI perl-DBD-MySQL [root@ProxySQL-node ~] # rpm -ivh proxysql-1.4.8-1-centos7.x86_64.rpm --force ??? 啟動proxysql [root@ProxySQL-node ~] # /etc/init.d/proxysql start Starting ProxySQL: DONE! [root@ProxySQL-node ~] # ss -lntup|grep proxy??? tcp??? LISTEN???? 0????? 128?????? *:6080????????????????? *:*?????????????????? users :(( "proxysql" ,pid=29931,fd=11)) tcp??? LISTEN???? 0????? 128?????? *:6032????????????????? *:*?????????????????? users :(( "proxysql" ,pid=29931,fd=28)) tcp??? LISTEN???? 0????? 128?????? *:6033????????????????? *:*?????????????????? users :(( "proxysql" ,pid=29931,fd=27)) tcp??? LISTEN???? 0????? 128?????? *:6033????????????????? *:*?????????????????? users :(( "proxysql" ,pid=29931,fd=26)) tcp??? LISTEN???? 0????? 128?????? *:6033????????????????? *:*?????????????????? users :(( "proxysql" ,pid=29931,fd=25)) tcp??? LISTEN???? 0????? 128?????? *:6033????????????????? *:*?????????????????? users :(( "proxysql" ,pid=29931,fd=24)) ??? [root@ProxySQL-node ~] # mysql -uadmin -padmin -h127.0.0.1 -P6032 ............ ............ MySQL [(none)]> show databases; +-----+---------------+-------------------------------------+ | seq | name????????? | file??????????????????????????????? | +-----+---------------+-------------------------------------+ | 0?? | main????????? |???????????????????????????????????? | | 2?? | disk????????? | /var/lib/proxysql/proxysql .db?????? | | 3?? | stats???????? |???????????????????????????????????? | | 4?? | monitor?????? |???????????????????????????????????? | | 5?? | stats_history | /var/lib/proxysql/proxysql_stats .db | +-----+---------------+-------------------------------------+ 5 rows in set (0.000 sec) 接著初始化Proxysql，將之前的proxysql數據都刪除 MySQL [(none)]> delete from scheduler ; Query OK, 0 rows affected (0.000 sec) ?? MySQL [(none)]> delete from mysql_servers; Query OK, 3 rows affected (0.000 sec) ?? MySQL [(none)]> delete from mysql_users; Query OK, 1 row affected (0.000 sec) ?? MySQL [(none)]> delete from mysql_query_rules; Query OK, 0 rows affected (0.000 sec) ?? MySQL [(none)]> delete from mysql_group_replication_hostgroups ; Query OK, 1 row affected (0.000 sec) ?? MySQL [(none)]> LOAD MYSQL VARIABLES TO RUNTIME; Query OK, 0 rows affected (0.000 sec) ?? MySQL [(none)]> SAVE MYSQL VARIABLES TO DISK; Query OK, 94 rows affected (0.175 sec) ?? MySQL [(none)]> LOAD MYSQL SERVERS TO RUNTIME; Query OK, 0 rows affected (0.003 sec) ?? MySQL [(none)]> SAVE MYSQL SERVERS TO DISK; Query OK, 0 rows affected (0.140 sec) ?? MySQL [(none)]> LOAD MYSQL USERS TO RUNTIME; Query OK, 0 rows affected (0.000 sec) ?? MySQL [(none)]> SAVE MYSQL USERS TO DISK; Query OK, 0 rows affected (0.050 sec) ?? MySQL [(none)]> LOAD SCHEDULER TO RUNTIME; Query OK, 0 rows affected (0.000 sec) ?? MySQL [(none)]> SAVE SCHEDULER TO DISK; Query OK, 0 rows affected (0.096 sec) ?? MySQL [(none)]> LOAD MYSQL QUERY RULES TO RUNTIME; Query OK, 0 rows affected (0.000 sec) ?? MySQL [(none)]> SAVE MYSQL QUERY RULES TO DISK; Query OK, 0 rows affected (0.156 sec) ?? MySQL [(none)]>

3）在數據庫端建立proxysql登入需要的帳號 （在三個MGR任意一個節點上操作，會自動同步到其他節點）

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[root@MGR-node1 ~] # mysql -p123456 ......... mysql> CREATE USER 'proxysql' @ '%' IDENTIFIED BY 'proxysql' ;??? Query OK, 0 rows affected (0.07 sec) mysql> GRANT ALL ON * . * TO? 'proxysql' @ '%' ; Query OK, 0 rows affected (0.06 sec) mysql> create user 'sbuser' @ '%' IDENTIFIED BY 'sbpass' ;??? Query OK, 0 rows affected (0.05 sec) mysql> GRANT ALL ON * . * TO 'sbuser' @ '%' ;? Query OK, 0 rows affected (0.08 sec) mysql> FLUSH PRIVILEGES;??? Query OK, 0 rows affected (0.07 sec)

4) 創建檢查MGR節點狀態的函數和視圖 （在三個MGR任意一個節點上操作，會自動同步到其他節點）

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在MGR-node1節點上，創建系統視圖sys.gr_member_routing_candidate_status，該視圖將為ProxySQL提供組復制相關的監控狀態指標。 下載addition_to_sys.sql腳本，在MGR-node1節點執行如下語句導入MySQL即可 (在mgr-node1節點的mysql執行后，會同步到其他兩個節點上)。 ?? 下載地址: https: //pan .baidu.com /s/1bNYHtExy2fmqwvEyQS3sWg 提取密碼：wst7 [root@MGR-node1 ~] # vim /root/addition_to_sys.sql USE sys; ?? DELIMITER $$ ?? CREATE FUNCTION IFZERO(a INT, b INT) RETURNS INT DETERMINISTIC RETURN IF(a = 0, b, a)$$ ?? CREATE FUNCTION LOCATE2(needle TEXT(10000), haystack TEXT(10000), offset INT) RETURNS INT DETERMINISTIC RETURN IFZERO(LOCATE(needle, haystack, offset), LENGTH(haystack) + 1)$$ ?? CREATE FUNCTION GTID_NORMALIZE(g TEXT(10000)) RETURNS TEXT(10000) DETERMINISTIC RETURN GTID_SUBTRACT(g, '' )$$ ?? CREATE FUNCTION GTID_COUNT(gtid_set TEXT(10000)) RETURNS INT DETERMINISTIC BEGIN ?? DECLARE result BIGINT DEFAULT 0; ?? DECLARE colon_pos INT; ?? DECLARE next_dash_pos INT; ?? DECLARE next_colon_pos INT; ?? DECLARE next_comma_pos INT; ?? SET gtid_set = GTID_NORMALIZE(gtid_set); ?? SET colon_pos = LOCATE2( ':' , gtid_set, 1); ?? WHILE colon_pos != LENGTH(gtid_set) + 1 DO ????? SET next_dash_pos = LOCATE2( '-' , gtid_set, colon_pos + 1); ????? SET next_colon_pos = LOCATE2( ':' , gtid_set, colon_pos + 1); ????? SET next_comma_pos = LOCATE2( ',' , gtid_set, colon_pos + 1); ????? IF next_dash_pos < next_colon_pos AND next_dash_pos < next_comma_pos THEN ??????? SET result = result + ????????? SUBSTR(gtid_set, next_dash_pos + 1, ???????????????? LEAST(next_colon_pos, next_comma_pos) - (next_dash_pos + 1)) - ????????? SUBSTR(gtid_set, colon_pos + 1, next_dash_pos - (colon_pos + 1)) + 1; ????? ELSE ??????? SET result = result + 1; ????? END IF; ????? SET colon_pos = next_colon_pos; ?? END WHILE; ?? RETURN result; END$$ ?? CREATE FUNCTION gr_applier_queue_length() RETURNS INT DETERMINISTIC BEGIN ?? RETURN (SELECT sys.gtid_count( GTID_SUBTRACT( (SELECT Received_transaction_set FROM performance_schema.replication_connection_status WHERE Channel_name = 'group_replication_applier' ), (SELECT @@global.GTID_EXECUTED) ))); END$$ ?? CREATE FUNCTION gr_member_in_primary_partition() RETURNS VARCHAR(3) DETERMINISTIC BEGIN ?? RETURN (SELECT IF( MEMBER_STATE= 'ONLINE' AND ((SELECT COUNT(*) FROM performance_schema.replication_group_members WHERE MEMBER_STATE != 'ONLINE' ) >= ((SELECT COUNT(*) FROM performance_schema.replication_group_members) /2 ) = 0), 'YES' , 'NO' ) FROM performance_schema.replication_group_members JOIN performance_schema.replication_group_member_stats USING(member_id)); END$$ ?? CREATE VIEW gr_member_routing_candidate_status AS SELECT sys.gr_member_in_primary_partition() as viable_candidate, IF( (SELECT (SELECT GROUP_CONCAT(variable_value) FROM performance_schema.global_variables WHERE variable_name IN ( 'read_only' , 'super_read_only' )) != 'OFF,OFF' ), 'YES' , 'NO' ) as read_only, sys.gr_applier_queue_length() as transactions_behind, Count_Transactions_in_queue as 'transactions_to_cert' from performance_schema.replication_group_member_stats;$$ ?? DELIMITER ; 導入addition_to_sys.sql文件數據 [root@MGR-node1 ~] # mysql -p123456 < /root/addition_to_sys.sql mysql: [Warning] Using a password on the command line interface can be insecure. 在三個mysql節點上可以查看該視圖： [root@MGR-node1 ~] # mysql -p123456 ............ mysql> select * from sys.gr_member_routing_candidate_status; +------------------+-----------+---------------------+----------------------+ | viable_candidate | read_only | transactions_behind | transactions_to_cert | +------------------+-----------+---------------------+----------------------+ | YES????????????? | NO??????? |?????????????????? 0 |??????????????????? 0 | +------------------+-----------+---------------------+----------------------+ 1 row in set (0.01 sec)

5) 在proxysql中增加帳號

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[root@ProxySQL-node ~] # mysql -uadmin -padmin -h127.0.0.1 -P6032 ........... MySQL [(none)]> INSERT INTO MySQL_users(username,password,default_hostgroup) VALUES ( 'proxysql' , 'proxysql' ,1); Query OK, 1 row affected (0.000 sec) ?? MySQL [(none)]> UPDATE global_variables SET variable_value= 'proxysql' where variable_name= 'mysql-monitor_username' ;?? Query OK, 1 row affected (0.001 sec) ?? MySQL [(none)]> UPDATE global_variables SET variable_value= 'proxysql' where variable_name= 'mysql-monitor_password' ; Query OK, 1 row affected (0.002 sec) ?? MySQL [(none)]> LOAD MYSQL SERVERS TO RUNTIME; Query OK, 0 rows affected (0.006 sec) ?? MySQL [(none)]> SAVE MYSQL SERVERS TO DISK; Query OK, 0 rows affected (0.387 sec) ?? 測試一下能否正常登入數據庫 [root@ProxySQL-node ~] # mysql -uproxysql -pproxysql -h 127.0.0.1 -P6033 -e"select @@hostname" +------------+ | @@ hostname | +------------+ | MGR-node1? | +------------+ =================================================================== 如果上面測試登錄時報錯: [root@ProxySQL-node ~] #? mysql -uproxysql -pproxysql -h 127.0.0.1 -P6033 -e"select @@hostname" ERROR 1045 (28000): ProxySQL Error: Access denied for user 'proxysql' @ '127.0.0.1' (using password: YES) 但是檢查發現，明明用戶名和密碼已經修改成proxysql:proxysql了 MySQL [(none)]> select * from global_variables;?? .......... | mysql-interfaces??????????????????????????????????? | 0.0.0.0:6033?????? | | mysql-default_schema??????????????????????????????? | information_schema | | mysql-stacksize???????????????????????????????????? | 1048576??????????? | | mysql-server_version??????????????????????????????? | 5.5.30???????????? | | mysql-connect_timeout_server??????????????????????? | 3000?????????????? | | mysql-monitor_username????????????????????????????? | proxysql?????????? | | mysql-monitor_password????????????????????????????? | proxysql?????????? | 解決辦法: 依次執行下面的命令 MySQL [(none)]> LOAD MYSQL VARIABLES TO RUNTIME; MySQL [(none)]> SAVE MYSQL VARIABLES TO DISK; MySQL [(none)]> LOAD MYSQL SERVERS TO RUNTIME; MySQL [(none)]> SAVE MYSQL SERVERS TO DISK; MySQL [(none)]> LOAD MYSQL USERS TO RUNTIME; MySQL [(none)]> SAVE MYSQL USERS TO DISK; MySQL [(none)]> LOAD SCHEDULER TO RUNTIME; MySQL [(none)]> SAVE SCHEDULER TO DISK; MySQL [(none)]> LOAD MYSQL QUERY RULES TO RUNTIME; MySQL [(none)]> SAVE MYSQL QUERY RULES TO DISK; ========================================================= 如果測試登錄再出現： [root@ProxySQL-node ~] # mysql -uproxysql -pproxysql -h 127.0.0.1 -P6033 -e"select @@hostname" ERROR 9001 (HY000) at line 1: Max connect timeout reached while reaching hostgroup 1 after 10000ms 這是因為后端三個mysql的MGR節點還沒有加入到proxysql中的原因，再進行完下面的步驟 "配置proxysql" 后就可以了 [root@ProxySQL-node ~] # mysql -uproxysql -pproxysql -h 127.0.0.1 -P6033 -e"select @@hostname" +------------+ | @@ hostname | +------------+ | MGR-node1? | +------------+

6) 配置proxysql

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[root@ProxySQL-node ~] # mysql -uadmin -padmin -h127.0.0.1 -P6032? ............. MySQL [(none)]> delete from mysql_servers; Query OK, 3 rows affected (0.000 sec) ?? MySQL [(none)]> insert into mysql_servers (hostgroup_id, hostname , port) values(1, '172.16.60.211' ,3306); Query OK, 1 row affected (0.001 sec) ?? MySQL [(none)]> insert into mysql_servers (hostgroup_id, hostname , port) values(1, '172.16.60.212' ,3306); Query OK, 1 row affected (0.000 sec) ?? MySQL [(none)]> insert into mysql_servers (hostgroup_id, hostname , port) values(1, '172.16.60.213' ,3306); Query OK, 1 row affected (0.000 sec) ?? MySQL [(none)]> insert into mysql_servers (hostgroup_id, hostname , port) values(2, '172.16.60.211' ,3306); Query OK, 1 row affected (0.000 sec) ?? MySQL [(none)]> insert into mysql_servers (hostgroup_id, hostname , port) values(2, '172.16.60.212' ,3306); Query OK, 1 row affected (0.000 sec) ?? MySQL [(none)]> insert into mysql_servers (hostgroup_id, hostname , port) values(2, '172.16.60.213' ,3306); Query OK, 1 row affected (0.000 sec) ?? MySQL [(none)]> select * from? mysql_servers ; +--------------+---------------+------+--------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | hostgroup_id | hostname????? | port | status | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment | +--------------+---------------+------+--------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | 1??????????? | 172.16.60.211 | 3306 | ONLINE | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.212 | 3306 | ONLINE | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.213 | 3306 | ONLINE | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.211 | 3306 | ONLINE | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.212 | 3306 | ONLINE | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.213 | 3306 | ONLINE | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | +--------------+---------------+------+--------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ 6 rows in set (0.001 sec) ?? hostgroup_id = 1代表write group，針對我們提出的限制，這個地方只配置了一個節點； hostgroup_id = 2代表 read group，包含了MGR的所有節點,目前只是Onlinle的，等配置過scheduler后，status就會有變化 。 ?? 對于上面的hostgroup配置，默認所有的寫操作會發送到hostgroup_id為1的online節點，也就是發送到寫節點上。 所有的讀操作，會發送為hostgroup_id為2的online節點。 ?? 需要確認一下沒有使用proxysql的讀寫分離規則（因為之前測試中配置了這個地方，所以需要刪除，以免影響后面的測試）。 MySQL [(none)]> delete from mysql_query_rules; Query OK, 2 rows affected (0.000 sec) ?? MySQL [(none)]> commit; Query OK, 0 rows affected (0.000 sec) ?? 最后需要將global_variables，mysql_servers、mysql_users表的信息加載到RUNTIME，更進一步加載到DISK: MySQL [(none)]> LOAD MYSQL VARIABLES TO RUNTIME; Query OK, 0 rows affected (0.001 sec) ?? MySQL [(none)]> SAVE MYSQL VARIABLES TO DISK; Query OK, 94 rows affected (0.080 sec) ?? MySQL [(none)]> LOAD MYSQL SERVERS TO RUNTIME; Query OK, 0 rows affected (0.003 sec) ?? MySQL [(none)]> SAVE MYSQL SERVERS TO DISK; Query OK, 0 rows affected (0.463 sec) ?? MySQL [(none)]> LOAD MYSQL USERS TO RUNTIME; Query OK, 0 rows affected (0.001 sec) ?? MySQL [(none)]> SAVE MYSQL USERS TO DISK; Query OK, 0 rows affected (0.134 sec) 再次驗證proxysql登錄 [root@ProxySQL-node ~] # mysql -uproxysql -pproxysql -h 127.0.0.1 -P6033 -e"select @@hostname" +------------+ | @@ hostname | +------------+ | MGR-node1? | +------------+

7）配置scheduler
首先，請在Github地址https://github.com/ZzzCrazyPig/proxysql_groupreplication_checker下載相應的腳本
這個地址有三個腳本可供下載：
proxysql_groupreplication_checker.sh：用于multi-primary模式，可以實現讀寫分離，以及故障切換，同一時間點多個節點可以多寫；
gr_mw_mode_cheker.sh：用于multi-primary模式，可以實現讀寫分離，以及故障切換，不過在同一時間點只能有一個節點能寫；
gr_sw_mode_checker.sh：用于single-primary模式，可以實現讀寫分離，以及故障切換；
由于這里實驗的環境是multi-primary模式，所以選擇proxysql_groupreplication_checker.sh腳本。

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三個腳本我已打包放在了百度云盤上，下載地址：https: //pan .baidu.com /s/1lUzr58BSA_U7wmYwsRcvzQ 提取密碼：9rm7 將下載的腳本proxysql_groupreplication_checker.sh放到目錄 /var/lib/proxysql/ 下，并增加可以執行的權限: [root@ProxySQL-node ~] # chmod a+x /var/lib/proxysql/proxysql_groupreplication_checker.sh [root@ProxySQL-node ~] # ll /var/lib/proxysql/proxysql_groupreplication_checker.sh?????? -rwxr-xr-x 1 root root 6081 Feb 20 14:25 /var/lib/proxysql/proxysql_groupreplication_checker .sh 最后，在proxysql的scheduler表里面加載如下記錄，然后加載到RUNTIME使其生效，同時還可以持久化到磁盤: 執行語句" INSERT INTO scheduler( id ,interval_ms,filename,arg1,arg2,arg3,arg4, arg5) VALUES (1, '10000' , '/var/lib/proxysql/proxysql_groupreplication_checker.sh' , '1' , '2' , '1' , '0' , '/var/lib/proxysql/proxysql_groupreplication_checker.log' );" 如下： [root@ProxySQL-node ~] # mysql -uadmin -padmin -h127.0.0.1 -P6032 .............. MySQL [(none)]> INSERT INTO scheduler( id ,interval_ms,filename,arg1,arg2,arg3,arg4, arg5) VALUES (1, '10000' , '/var/lib/proxysql/proxysql_groupreplication_checker.sh' , '1' , '2' , '1' , '0' , '/var/lib/proxysql/proxysql_groupreplication_checker.log' ); Query OK, 1 row affected (0.000 sec) MySQL [(none)]> select * from scheduler; +----+--------+-------------+--------------------------------------------------------+------+------+------+------+---------------------------------------------------------+---------+ | id | active | interval_ms | filename?????????????????????????????????????????????? | arg1 | arg2 | arg3 | arg4 | arg5??????????????????????????????????????????????????? | comment | +----+--------+-------------+--------------------------------------------------------+------+------+------+------+---------------------------------------------------------+---------+ | 1? | 1????? | 10000?????? | /var/lib/proxysql/proxysql_groupreplication_checker .sh | 1??? | 2??? | 1??? | 0??? | /var/lib/proxysql/proxysql_groupreplication_checker .log |???????? | +----+--------+-------------+--------------------------------------------------------+------+------+------+------+---------------------------------------------------------+---------+ 1 row in set (0.000 sec) MySQL [(none)]> LOAD SCHEDULER TO RUNTIME; Query OK, 0 rows affected (0.001 sec) MySQL [(none)]> SAVE SCHEDULER TO DISK; Query OK, 0 rows affected (0.118 sec) ============================================================================== scheduler各column的說明： active : 1: enable scheduler to schedule the script we provide interval_ms : invoke one by one in cycle (eg: 5000(ms) = 5s represent every 5s invoke the script) filename: represent the script file path arg1~arg5: represent the input parameters the script received 腳本proxysql_groupreplication_checker.sh對應的參數說明如下: arg1 is the hostgroup_id for write arg2 is the hostgroup_id for read arg3 is the number of writers we want active at the same time arg4 represents if we want that the member acting for writes is also candidate for reads arg5 is the log file schedule信息加載后，就會分析當前的環境，mysql_servers中顯示出當前只有172.16.60.211是可以寫的， 172.16.60.212以及172.16.60.213是用來讀的。 MySQL [(none)]> select * from? mysql_servers ;????????????? // 上面操作后，稍等一會兒后執行此命令才會有下面的結果 +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | hostgroup_id | hostname????? | port | status?????? | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | 1??????????? | 172.16.60.211 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.212 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.213 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.211 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.212 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.213 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ 6 rows in set (0.000 sec) 因為schedule的arg4，我這里設為了0，就表示可寫的節點不能用于讀。那我將arg4設置為1試一下： MySQL [(none)]> update scheduler set arg4=1; Query OK, 1 row affected (0.000 sec) MySQL [(none)]> select * from scheduler; +----+--------+-------------+--------------------------------------------------------+------+------+------+------+---------------------------------------------------------+---------+ | id | active | interval_ms | filename?????????????????????????????????????????????? | arg1 | arg2 | arg3 | arg4 | arg5??????????????????????????????????????????????????? | comment | +----+--------+-------------+--------------------------------------------------------+------+------+------+------+---------------------------------------------------------+---------+ | 1? | 1????? | 10000?????? | /var/lib/proxysql/proxysql_groupreplication_checker .sh | 1??? | 2??? | 1??? | 1??? | /var/lib/proxysql/proxysql_groupreplication_checker .log |???????? | +----+--------+-------------+--------------------------------------------------------+------+------+------+------+---------------------------------------------------------+---------+ 1 row in set (0.000 sec) MySQL [(none)]> SAVE SCHEDULER TO DISK; Query OK, 0 rows affected (0.286 sec) MySQL [(none)]> LOAD SCHEDULER TO RUNTIME; Query OK, 0 rows affected (0.000 sec) MySQL [(none)]> select * from? mysql_servers;????????? // 上面操作后，稍微等一會兒執行此命令才會有下面的結果 +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | hostgroup_id | hostname????? | port | status?????? | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | 1??????????? | 172.16.60.211 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.212 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.213 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.211 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.212 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.213 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ 6 rows in set (0.000 sec) arg4設置為1之后，172.16.60.211節點用來寫的同時，也可以被用來讀。 便于下面的測試還是將arg4設為0： MySQL [(none)]> update scheduler set arg4=0; Query OK, 1 row affected (0.000 sec) MySQL [(none)]> SAVE SCHEDULER TO DISK; Query OK, 0 rows affected (0.197 sec) MySQL [(none)]> LOAD SCHEDULER TO RUNTIME; Query OK, 0 rows affected (0.000 sec) MySQL [(none)]> select * from? mysql_servers;???????????? // 稍微等一會兒執行此命令，才會有下面的結果 +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | hostgroup_id | hostname????? | port | status?????? | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | 1??????????? | 172.16.60.211 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.212 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.213 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.211 | 3306 | OFFLINE_SORT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.212 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.213 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ 6 rows in set (0.000 sec) 各個節點的gr_member_routing_candidate_status視圖也顯示了當前節點是否是正常狀態的， proxysql就是讀取的這個視圖的信息來決定此節點是否可用。 [root@MGR-node1 ~] # mysql -p123456????????????? ........... mysql> select * from sys.gr_member_routing_candidate_status\G; *************************** 1. row *************************** ???? viable_candidate: YES ??????????? read_only: NO ? transactions_behind: 0 transactions_to_cert: 0 1 row in set (0.00 sec) ERROR: No query specified

8) 設置讀寫分離

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49

MySQL [(none)]> insert into mysql_query_rules (active, match_pattern, destination_hostgroup, apply) values (1, "^SELECT" ,2,1); Query OK, 1 row affected (0.001 sec) MySQL [(none)]> LOAD MYSQL QUERY RULES TO RUNTIME; Query OK, 0 rows affected (0.001 sec) MySQL [(none)]> SAVE MYSQL QUERY RULES TO DISK; Query OK, 0 rows affected (0.264 sec) 解釋說明: match_pattern的規則是基于正則表達式的， active表示是否啟用這個sql路由項， match_pattern就是我們正則匹配項， destination_hostgroup表示我們要將該類sql轉發到哪些mysql上面去，這里我們將 select 轉發到group 2，。 apply為1表示該正則匹配后，將不再接受其他匹配，直接轉發。 對于 for update需要在gruop1上執行，可以加上規則： MySQL [(none)]> insert into mysql_query_rules(active,match_pattern,destination_hostgroup,apply) values(1, '^SELECT.*FOR UPDATE$' ,1,1); Query OK, 1 row affected (0.001 sec) 在proxysql本機或其他客戶機上檢查下， select 語句，一直連接的是172.16.60.212和172.16.60.213 [root@MGR-node3 ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select @@hostname" mysql: [Warning] Using a password on the command line interface can be insecure. +------------+ | @@ hostname | +------------+ | MGR-node3? | +------------+ [root@MGR-node3 ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select @@hostname" mysql: [Warning] Using a password on the command line interface can be insecure. +------------+ | @@ hostname | +------------+ | MGR-node2? | +------------+ [root@MGR-node3 ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select @@hostname" mysql: [Warning] Using a password on the command line interface can be insecure. +------------+ | @@ hostname | +------------+ | MGR-node2? | +------------+ [root@MGR-node3 ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select @@hostname" mysql: [Warning] Using a password on the command line interface can be insecure. +------------+ | @@ hostname | +------------+ | MGR-node3? | +------------+

9) 驗證數據的讀寫分離效果

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76

[root@ProxySQL-node ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select @@hostname"?? +------------+ | @@ hostname | +------------+ | MGR-node2? | +------------+ [root@ProxySQL-node ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select * from kevin.haha" +-----+-----------+ | id? | name????? | +-----+-----------+ |?? 1 | wangshibo | |?? 2 | guohuihui | |? 11 | beijing?? | | 100 | anhui???? | +-----+-----------+ [root@ProxySQL-node ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "delete from kevin.haha where id=1;"????????????????????? [root@ProxySQL-node ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "delete from kevin.haha where id=2;" [root@ProxySQL-node ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select * from kevin.haha"??????????????? +-----+---------+ | id? | name??? | +-----+---------+ |? 11 | beijing | | 100 | anhui?? | +-----+---------+ [root@ProxySQL-node ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e 'insert into kevin.haha values(21,"zhongguo"),(22,"xianggang"),(23,"taiwan");' [root@ProxySQL-node ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select * from kevin.haha"??????????????????????????????? +-----+-----------+ | id? | name????? | +-----+-----------+ |? 11 | beijing?? | |? 21 | zhongguo? | |? 22 | xianggang | |? 23 | taiwan??? | | 100 | anhui???? | 最后在proxysql管理端查看讀寫分離情況 [root@ProxySQL-node ~] # mysql -uadmin -padmin -h 127.0.0.1 -P6032 .......... MySQL [(none)]> select hostgroup,username,digest_text,count_star from stats_mysql_query_digest; +-----------+----------+------------------------------------------------------+------------+ | hostgroup | username | digest_text????????????????????????????????????????? | count_star | +-----------+----------+------------------------------------------------------+------------+ | 1???????? | proxysql | insert into kevin.haha values(?,?),(?,?),(?,?)?????? | 1????????? | | 1???????? | proxysql | insert into kevin.haha values(?,yangyang)??????????? | 1????????? | | 1???????? | proxysql | delete from kevin.haha where id =???????????????????? | 2????????? | | 1???????? | proxysql | select @@version_comment limit ????????????????????? | 120??????? | | 1???????? | proxysql | KILL ??????????????????????????????????????????????? | 8????????? | | 1???????? | proxysql | select @@ hostname??????????????????????????????????? | 11???????? | | 1???????? | proxysql | KILL QUERY ????????????????????????????????????????? | 10???????? | | 2???????? | proxysql | select @@ hostname , sleep (?)????????????????????????? | 53???????? | | 1???????? | proxysql | insert into kevin.haha values(?,yangyang),(?,shikui) | 2????????? | | 1???????? | proxysql | show databases?????????????????????????????????????? | 1????????? | | 2???????? | proxysql | select @@ hostname??????????????????????????????????? | 31???????? | | 2???????? | proxysql | select * from kevin.haha???????????????????????????? | 4????????? | | 1???????? | proxysql | insert into kevin.haha values(?,wawa)??????????????? | 3????????? | +-----------+----------+------------------------------------------------------+------------+ 13 rows in set (0.002 sec) MySQL [(none)]> select * from? mysql_servers; +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | hostgroup_id | hostname????? | port | status?????? | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | 1??????????? | 172.16.60.211 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.212 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.213 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.211 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.212 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.213 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ 6 rows in set (0.000 sec) 通過上面可以看到： 寫操作都分配到了group1組內，即寫操作分配到172.16.60.211節點上。 讀操作都分配到了group2組內，即讀操作分配到172.16.60.212、172.16.60.213節點上。

10）設置故障應用無感應

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在上面的讀寫分離規則中，我設置了172.16.60.211為可寫節點，172.16.60.212,172.16.60.213為只讀節點 如果此時172.16.60.211變成只讀模式的話，應用能不能直接連到其它的節點進行寫操作？ ?? 現手動將172.16.60.211變成只讀模式： [root@MGR-node1 ~] # mysql -p123456 ........ mysql> set global read_only=1; Query OK, 0 rows affected (0.00 sec) ?? 接著觀察一下mysql_servers的狀態，自動將group1的172.16.60.212改成了online，group2的172.16.60.211, 172.16.60.213變成online了，就表示將172.16.60.212變為可寫節點，其它兩個節點變為只讀節點了。 ?? [root@ProxySQL-node ~] # mysql -uadmin -padmin -h 127.0.0.1 -P6032 ........ MySQL [(none)]> select * from? mysql_servers; +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | hostgroup_id | hostname????? | port | status?????? | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | 1??????????? | 172.16.60.211 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.212 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.213 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.211 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.212 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.213 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ 6 rows in set (0.001 sec) ?? 通過模擬的連接也可以看到 select 語句都連接到172.16.60.211和172.16.60.213進行了。 (模擬時可以稍微間隔一段時間，快速測試可能會連接同一個讀節點) [root@MGR-node3 ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select @@hostname" mysql: [Warning] Using a password on the command line interface can be insecure. +------------+ | @@ hostname | +------------+ | MGR-node3? | +------------+ [root@MGR-node3 ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select @@hostname" mysql: [Warning] Using a password on the command line interface can be insecure. +------------+ | @@ hostname | +------------+ | MGR-node1? | +------------+ [root@MGR-node3 ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select @@hostname" mysql: [Warning] Using a password on the command line interface can be insecure. +------------+ | @@ hostname | +------------+ | MGR-node3? | +------------+ [root@MGR-node3 ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select @@hostname" mysql: [Warning] Using a password on the command line interface can be insecure. +------------+ | @@ hostname | +------------+ | MGR-node1? | +------------+ [root@MGR-node3 ~] # mysql -uproxysql -pproxysql -h172.16.60.214 -P6033 -e "select @@hostname" mysql: [Warning] Using a password on the command line interface can be insecure. +------------+ | @@ hostname | +------------+ | MGR-node1? | +------------+ ?? 然后再將將172.16.60.211變為可寫模式后，mysql_servers也恢復過來了。 [root@MGR-node1 ~] # mysql -p123456 ........ mysql> set global read_only=0; Query OK, 0 rows affected (0.00 sec) ?? 接著觀察一下mysql_servers的狀態 [root@ProxySQL-node ~] # mysql -uadmin -padmin -h 127.0.0.1 -P6032 ......... MySQL [(none)]> select * from? mysql_servers; +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | hostgroup_id | hostname????? | port | status?????? | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | 1??????????? | 172.16.60.211 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.212 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.213 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.211 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.212 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.213 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ 6 rows in set (0.000 sec) ?? 經過測試將172.16.60.211節點停止組復制（stop group_replication）或者該節點宕機(mysql服務掛掉)后，mysql_servers表的信息也會正常的切換新的節點。 待172.16.60.211恢復再加入到組復制后，mysql_servers也會正常的將172.16.60.211改成online狀態。 ====================================================================================================== 可能出現的問題: mysql>? select * from? mysql_servers ; +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | hostgroup_id | hostname????? | port | status?????? | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | 1??????????? | 172.16.60.211 | 3306 | OFFLINE_HARD | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.211 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.212 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.213 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ 4 rows in set (0.00 sec) 也就是說，可能遇到上面所有節點都offline了的情況，查看錯誤日志如下： [root@ProxySQL-node ~] # tail -f /var/lib/proxysql/proxysql.log ........ [2019-02-18 16:23:52] read node [hostgroup_id: 2, hostname : 172.16.60.213, port: 3306, isOK: 0] is not OK, we will set it 's status to be ' OFFLINE_SOFT' ERROR 1142 (42000) at line 1: SELECT command denied to user 'proxysql' @ '172.16.60.214' for table 'gr_member_routing_candidate_status' [2019-02-18 16:23:55] current write node [hostgroup_id: 2, hostname : 172.17.61.131, port: 3306, isOK: 0] is not OK, we need to do switch over ERROR 1142 (42000) at line 1: SELECT command denied to user 'proxysql' @ '172.16.60.214' for table 'gr_member_routing_candidate_status' [2019-02-18 16:23:55] read node [hostgroup_id: 2, hostname : 172.17.61.132, port: 3306, isOK: 0] is not OK, we will set it 's status to be ' OFFLINE_SOFT' ERROR 1142 (42000) at line 1: SELECT command denied to user 'proxysql' @ '172.16.60.214' for table 'gr_member_routing_candidate_status 從上面的錯誤日志上看出是權限的問題，proxysql用戶沒有足夠的權限讀取數據。 解決辦法： [root@MGR-node1 ~] # mysql -p123456 ......... mysql> GRANT ALL ON * . * TO? 'proxysql' @ '%' ;? mysql> flush privileges; 再次看看，就有權限了 [root@ProxySQL-node ~] # mysql -uadmin -padmin -h 127.0.0.1 -P6032 ......... MySQL [(none)]> select * from? mysql_servers; +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | hostgroup_id | hostname????? | port | status?????? | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ | 1??????????? | 172.16.60.211 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.212 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 1??????????? | 172.16.60.213 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.211 | 3306 | OFFLINE_SOFT | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.212 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | | 2??????????? | 172.16.60.213 | 3306 | ONLINE?????? | 1????? | 0?????????? | 1000??????????? | 0?????????????????? | 0?????? | 0????????????? |???????? | +--------------+---------------+------+--------------+--------+-------------+-----------------+---------------------+---------+----------------+---------+ 6 rows in set (0.000 sec)

到此，ProxySQL就簡單實現了MGR的讀寫分離和主節點故障無感知環境。

***************當你發現自己的才華撐不起野心時，就請安靜下來學習吧*************** 分類: Mysql

轉載于:https://my.oschina.net/rootliu/blog/3095004

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