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ProxySQL构建PolarDB-X标准版高可用路由服务三节点集群

ProxySQL构建PolarDB-X标准版高可用路由服务三节点集群

一、PolarDB-X标准版主备集群搭建

三台机器上传 polardbx 包,包可以从官网https://openpolardb.com/download获取,这里提供离线rpm。

1、上传 polardbx 安装包 到 /opt目录下

rpm -ivh   t-polardbx-engine-8.4.19-20241112.el7.x86_64.rpm

会出现 :
(base) [root@cdh-alpha opt]# ll polardbx_engine/
total 708
drwxr-xr-x  2 root root   4096 Feb 11 13:56 bin
drwxr-xr-x  2 root root    107 Feb 11 13:56 docs
drwxr-xr-x  3 root root   4096 Feb 11 13:56 include
drwxr-xr-x  6 root root    247 Feb 11 13:56 lib
-rwxr-xr-x  1 root root 283374 Feb 11 13:56 LICENSE
-rwxr-xr-x  1 root root 121462 Feb 11 13:56 LICENSE.router
-rwxr-xr-x  1 root root 283374 Feb 11 13:56 LICENSE-test
drwxr-xr-x  4 root root     42 Feb 11 13:56 man
-rwxr-xr-x  1 root root   1622 Feb 11 13:56 mysqlrouter-log-rotate
-rwxr-xr-x  1 root root    952 Feb 11 13:56 README
-rwxr-xr-x  1 root root    679 Feb 11 13:56 README.router
-rwxr-xr-x  1 root root    952 Feb 11 13:56 README-test
drwxr-xr-x  2 root root     10 Feb 11 13:56 run
drwxr-xr-x 28 root root   4096 Feb 11 13:56 share
drwxr-xr-x  2 root root     93 Feb 11 13:56 support-files
drwxr-xr-x  3 root root     25 Feb 11 13:56 var
(base) [root@cdh-alpha opt]#

2、创建 polarx 用户

(您也可以使用其他非 root 用户),准备一份 my.cnf(参考模板)和数据目录(如果改了 my.cnf,则下面的目录也要相应修改)

创建并切换到 polarx 用户

useradd -ms /bin/bash polarx
echo "polarx:polarx" | chpasswd
echo "polarx    ALL=(ALL)    NOPASSWD: ALL" >> /etc/sudoers
su - polarx

创建必要目录

mkdir polardbx-engine
cd polardbx-engine && mkdir log mysql run data tmp

准备一份 my.cnf 文件,可以参考本文末尾的模板,放置于当前目录,my.cnf 参考模板,请根据实际情况修改参数,仅验证功能和测试,更多参数可参考完整参数模板。附参考:

vi my.cnf

###### my.cnf 模板
[mysqld]
basedir = /opt/polardbx_engine
log_error_verbosity = 2
default_authentication_plugin = mysql_native_password
gtid_mode = ON
enforce_gtid_consistency = ON
log_bin = mysql-binlog
binlog_format = row
binlog_row_image = FULL
master_info_repository = TABLE
relay_log_info_repository = TABLE
# 忽略大小写
lower_case_table_names=1
 
# change me if needed
datadir = /home/polarx/polardbx-engine/data
tmpdir = /home/polarx/polardbx-engine/tmp
socket = /home/polarx/polardbx-engine/tmp.mysql.sock
log_error = /home/polarx/polardbx-engine/log/alert.log
port = 4886
cluster_id = 1
cluster_info = 10.10.6.47:14886@1,10.10.6.48:14886@2,10.10.6.49:14886@3
server_id = 123
 
[mysqld_safe]
pid_file = /home/polarx/polardbx-engine/run/mysql.pid

###### my.cnf 模板

注意:这里讲集群模式的my.cnf  配置, 如果以三副本模式运行,my.cnf 中的 server_id 参数在三个副本节点需要配置为不同的值
 

3、集群初始化、启动

在 3 台机器上,按前述步骤,安装 RPM 后,准备好 my.cnf 和目录 (如果有任何步骤失败,请完全清理 log mysql run data tmp 等目录,重新创建。)。 然后在 3 个机器上,分别按如下方式启动: 如果 my.cnf 不在当前目录,请将下述命令的 my.cnf 改成绝对路径
10.10.6.47初始化:
/opt/polardbx_engine/bin/mysqld --defaults-file=my.cnf  --cluster-info='10.10.6.47:14886;10.10.6.48:14886;10.10.6.49:14886@1'   --initialize-insecure
启动
/opt/polardbx_engine/bin/mysqld_safe --defaults-file=my.cnf --cluster-info='10.10.6.47:14886;10.10.6.48:14886;10.10.6.49:14886@1' &



10.10.6.48初始化:
/opt/polardbx_engine/bin/mysqld --defaults-file=my.cnf  --cluster-info='10.10.6.47:14886;10.10.6.48:14886;10.10.6.49:14886@2'   --initialize-insecure
启动
/opt/polardbx_engine/bin/mysqld_safe --defaults-file=my.cnf --cluster-info='10.10.6.47:14886;10.10.6.48:14886;10.10.6.49:14886@2' &



10.10.6.49初始化:
/opt/polardbx_engine/bin/mysqld --defaults-file=my.cnf  --cluster-info='10.10.6.47:14886;10.10.6.48:14886;10.10.6.49:14886@3'   --initialize-insecure
启动
/opt/polardbx_engine/bin/mysqld_safe --defaults-file=my.cnf --cluster-info='10.10.6.47:14886;10.10.6.48:14886;10.10.6.49:14886@3' &

稍等片刻,即可登录三台数据库。如果直接使用本文的 my.cnf 模板,可以用mysql -h127.0.0.1 -P4886 -uroot 登录数据库。 (需要预先在机器上安装 mysql 客户端,centos 系统可以使用 yum install mysql 安装。)

[polarx@cdh-alpha polardbx-engine]$ mysql -h127.0.0.1 -P4886 -uroot
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 990
Server version: 8.0.32-X-Cluster-8.4.19-20241112 Source distribution

Copyright (c) 2000, 2022, Oracle and/or its affiliates.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> 

4、验证集群状态

数据库启动完成后,我们登录数据库,验证一下集群的状态。(需要在 Leader 节点执行)

mysql> SELECT * FROM INFORMATION_SCHEMA.ALISQL_CLUSTER_GLOBAL;
+-----------+------------------+-------------+------------+----------+-----------+------------+-----------------+----------------+---------------+------------+--------------+
| SERVER_ID | IP_PORT          | MATCH_INDEX | NEXT_INDEX | ROLE     | HAS_VOTED | FORCE_SYNC | ELECTION_WEIGHT | LEARNER_SOURCE | APPLIED_INDEX | PIPELINING | SEND_APPLIED |
+-----------+------------------+-------------+------------+----------+-----------+------------+-----------------+----------------+---------------+------------+--------------+
|         1 | 10.10.6.47:14886 |          18 |         19 | Follower | Yes       | No         |               5 |              0 |            18 | Yes        | No           |
|         2 | 10.10.6.48:14886 |          18 |         19 | Follower | Yes       | No         |               5 |              0 |            18 | Yes        | No           |
|         3 | 10.10.6.49:14886 |          18 |          0 | Leader   | Yes       | No         |               5 |              0 |            17 | No         | No           |
+-----------+------------------+-------------+------------+----------+-----------+------------+-----------------+----------------+---------------+------------+--------------+
3 rows in set (0.00 sec)

mysql> 

mysql> SELECT * FROM INFORMATION_SCHEMA.ALISQL_CLUSTER_LOCAL \G
*************************** 1. row ***************************
          SERVER_ID: 3
       CURRENT_TERM: 41
     CURRENT_LEADER: 10.10.6.49:14886
       COMMIT_INDEX: 18
      LAST_LOG_TERM: 41
     LAST_LOG_INDEX: 18
               ROLE: Leader
          VOTED_FOR: 3
   LAST_APPLY_INDEX: 17
SERVER_READY_FOR_RW: Yes
      INSTANCE_TYPE: Normal
1 row in set (0.00 sec)

mysql> 

5、数据库操作

数据插入测试:

CREATE DATABASE db1;
USE db1;
CREATE TABLE tb1 (id int);
INSERT INTO tb1 VALUES (0), (1), (2);

MySQL [db1]> select * from tb1;
+------+
| id   |
+------+
|    0 |
|    1 |
|    2 |
+------+
3 rows in set (0.001 sec)

至此,三台主备集群搭建完成,可自行kill主,查看切换主备集群自动切换,接下来搭建 高可用路由配置 :

======================================================================================================

======================================================================================================

二、ProxySQL构建PolarDB-X集群高可用

1、配置PolarDB-X标准版

创建依赖视图,目的让ProxySQL识别PolarDB-X标准版的元数据(Leader、Follower)

CREATE VIEW sys.gr_member_routing_candidate_status AS 
SELECT IF(ROLE='Leader' OR ROLE='Follower', 'YES', 'NO' ) as viable_candidate,
       IF(ROLE <>'Leader', 'YES', 'NO' ) as read_only,
       IF (ROLE = 'Leader', 0, LAST_LOG_INDEX - LAST_APPLY_INDEX) as transactions_behind,
       0 as 'transactions_to_cert' 
FROM information_schema.ALISQL_CLUSTER_LOCAL;

创建ProxySql的监控账户,ProxySQL运行通用依赖

create user 'proxysql_monitor'@'%' identified with mysql_native_password by '123456';
GRANT SELECT on sys.* to 'proxysql_monitor'@'%';

创建测试账户,下面高可用测试依赖

create user 'admin2'@'%' identified with mysql_native_password by '123456';
GRANT all privileges on *.* to 'admin2'@'%';

检查配置是否生效

mysql> select @@port;
+--------+
| @@port |
+--------+
|   4886 |
+--------+
1 row in set (0.00 sec)


mysql> select * from information_schema.ALISQL_CLUSTER_GLOBAL;
+-----------+------------------+-------------+------------+----------+-----------+------------+-----------------+----------------+---------------+------------+--------------+
| SERVER_ID | IP_PORT          | MATCH_INDEX | NEXT_INDEX | ROLE     | HAS_VOTED | FORCE_SYNC | ELECTION_WEIGHT | LEARNER_SOURCE | APPLIED_INDEX | PIPELINING | SEND_APPLIED |
+-----------+------------------+-------------+------------+----------+-----------+------------+-----------------+----------------+---------------+------------+--------------+
|         1 | 10.10.6.47:14886 |          18 |         19 | Follower | Yes       | No         |               5 |              0 |            18 | Yes        | No           |
|         2 | 10.10.6.48:14886 |          18 |         19 | Follower | Yes       | No         |               5 |              0 |            18 | Yes        | No           |
|         3 | 10.10.6.49:14886 |          18 |          0 | Leader   | Yes       | No         |               5 |              0 |            17 | No         | No           |
+-----------+------------------+-------------+------------+----------+-----------+------------+-----------------+----------------+---------------+------------+--------------+
3 rows in set (0.00 sec)


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 (0.00 sec)

mysql>  select User,Host from mysql.user where User in ('admin2', 'proxysql_monitor');
+------------------+------+
| User             | Host |
+------------------+------+
| admin2           | %    |
| proxysql_monitor | %    |
+------------------+------+
2 rows in set (0.00 sec)


2、ProxySQL部署

1、依赖包

选择一台性能高机器,依赖包获取官网:https://github.com/sysown/proxysql/releases/tag/v2.4.8 ,本文提供离线rpm包:

wget https://github.com/sysown/proxysql/releases/download/v2.4.8/proxysql-2.4.8-1-centos7.x86_64.rpm

(base) [root@cdh-alpha opt]# ll proxysql-2.4.8-1-centos7.x86_64.rpm
-rw-rw-rw- 1 root root 16422372 Feb 15  2023 proxysql-2.4.8-1-centos7.x86_64.rpm
(base) [root@cdh-alpha opt]#

本地安装

sudo rpm -ivh proxysql-2.4.8-1-centos7.x86_64.rpm --nodeps

启动ProxySQL

(base) [root@cdh-alpha opt]# sudo systemctl start proxysql

(base) [root@cdh-alpha opt]# sudo systemctl status proxysql
● proxysql.service - High Performance Advanced Proxy for MySQL
   Loaded: loaded (/etc/systemd/system/proxysql.service; enabled; vendor preset: disabled)
   Active: active (running) since Thu 2025-02-13 18:50:39 CST; 17h ago
  Process: 23894 ExecStart=/usr/bin/proxysql --idle-threads -c /etc/proxysql.cnf $PROXYSQL_OPTS (code=exited, status=0/SUCCESS)
 Main PID: 23896 (proxysql)
    Tasks: 32
   Memory: 31.0M
   CGroup: /system.slice/proxysql.service
           ├─23896 /usr/bin/proxysql --idle-threads -c /etc/proxysql.cnf
           └─23897 /usr/bin/proxysql --idle-threads -c /etc/proxysql.cnf

Feb 13 18:50:39 cdh-alpha systemd[1]: Starting High Performance Advanced Proxy for MySQL...
Feb 13 18:50:39 cdh-alpha proxysql[23894]: 2025-02-13 18:50:39 [INFO] Using config file /etc/proxysql.cnf
Feb 13 18:50:39 cdh-alpha proxysql[23894]: 2025-02-13 18:50:39 [INFO] Current RLIMIT_NOFILE: 102400
Feb 13 18:50:39 cdh-alpha proxysql[23894]: 2025-02-13 18:50:39 [INFO] Using OpenSSL version: OpenSSL 3.0.8 7 Feb 2023
Feb 13 18:50:39 cdh-alpha proxysql[23894]: 2025-02-13 18:50:39 [INFO] SSL keys/certificates found in datadir (/var/lib/proxysql): loading them.
Feb 13 18:50:39 cdh-alpha systemd[1]: Started High Performance Advanced Proxy for MySQL.
You have mail in /var/spool/mail/root

2、配置

  • 登陆账户
mysql -uadmin -padmin -h 127.0.0.1 -P 6032 -A

  • 检查确保mysql_servers、mysql_group_replication_hostgroups、mysql_query_rules为空
#检查
mysql> select * from mysql_group_replication_hostgroups;
Empty set (0.00 sec)

mysql> select * from mysql_servers;
Empty set (0.00 sec)

mysql> select * from mysql_query_rules;
Empty set (0.00 sec)
  • 更新监控账号
UPDATE global_variables SET variable_value='proxysql_monitor' WHERE variable_name='mysql-monitor_username';
UPDATE global_variables SET variable_value='123456' WHERE variable_name='mysql-monitor_password';

#检查:
mysql> select * from global_variables where variable_name in ('mysql-monitor_username', 'mysql-monitor_password');
+------------------------+------------------+
| variable_name          | variable_value   |
+------------------------+------------------+
| mysql-monitor_password | 123456           |
| mysql-monitor_username | proxysql_monitor |
+------------------------+------------------+
2 rows in set (0.00 sec)
  • 添加测试账号
INSERT INTO mysql_users(username,password,default_hostgroup) VALUES ('admin2','123456',10);

#检查
mysql> select * from mysql_users;
+----------+----------+--------+---------+-------------------+----------------+---------------+------------------------+--------------+---------+----------+-----------------+------------+---------+
| username | password | active | use_ssl | default_hostgroup | default_schema | schema_locked | transaction_persistent | fast_forward | backend | frontend | max_connections | attributes | comment |
+----------+----------+--------+---------+-------------------+----------------+---------------+------------------------+--------------+---------+----------+-----------------+------------+---------+
| admin2   | 123456   | 1      | 0       | 10                | NULL           | 0             | 1                      | 0            | 1       | 1        | 10000           |            |         |
+----------+----------+--------+---------+-------------------+----------------+---------------+------------------------+--------------+---------+----------+-----------------+------------+---------+
1 row in set (0.00 sec)
  • 设置读写组,写组10,备写组20,读组30,离线组40,主节点可作为读节点
INSERT INTO mysql_group_replication_hostgroups (writer_hostgroup,backup_writer_hostgroup,reader_hostgroup,offline_hostgroup,active,writer_is_also_reader) VALUES(10,20,30,40,1,1);

#检查
mysql> select * from mysql_group_replication_hostgroups;
+------------------+-------------------------+------------------+-------------------+--------+-------------+-----------------------+-------------------------+---------+
| writer_hostgroup | backup_writer_hostgroup | reader_hostgroup | offline_hostgroup | active | max_writers | writer_is_also_reader | max_transactions_behind | comment |
+------------------+-------------------------+------------------+-------------------+--------+-------------+-----------------------+-------------------------+---------+
| 10               | 20                      | 30               | 40                | 1      | 1           | 1                     | 0                       | NULL    |
+------------------+-------------------------+------------------+-------------------+--------+-------------+-----------------------+-------------------------+---------+
1 row in set (0.00 sec)
  • 添加后端mysql_servers,leader节点定义为写组10, follower节点定义为备写库20。 注意这里port为节点的PolarDB-X标准版的监听端口port。
INSERT INTO mysql_servers(hostgroup_id,hostname,port) VALUES (10,'10.10.6.49',4886);
INSERT INTO mysql_servers(hostgroup_id,hostname,port) VALUES (20,'10.10.6.47',4886);
INSERT INTO mysql_servers(hostgroup_id,hostname,port) VALUES (20,'10.10.6.48',4886);

#检查
mysql> select * from mysql_servers;
+--------------+------------+------+-----------+--------+--------+-------------+-----------------+---------------------+---------+----------------+---------+
| hostgroup_id | hostname   | port | gtid_port | status | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment |
+--------------+------------+------+-----------+--------+--------+-------------+-----------------+---------------------+---------+----------------+---------+
| 10           | 10.10.6.49 | 4886 | 0         | ONLINE | 1      | 0           | 1000            | 0                   | 0       | 0              |         |
| 20           | 10.10.6.47 | 4886 | 0         | ONLINE | 1      | 0           | 1000            | 0                   | 0       | 0              |         |
| 20           | 10.10.6.48 | 4886 | 0         | ONLINE | 1      | 0           | 1000            | 0                   | 0       | 0              |         |
+--------------+------------+------+-----------+--------+--------+-------------+-----------------+---------------------+---------+----------------+---------+
3 rows in set (0.00 sec)
  • 配置读写分离规则。对于SELECT FOR UPDATE配置到写库,纯SELECT配置到读库。
INSERT INTO mysql_query_rules(active,match_pattern,destination_hostgroup,apply) VALUES(1,'^select.*for update$',10,1);
INSERT INTO mysql_query_rules(active,match_pattern,destination_hostgroup,apply) VALUES(1,'^select',30,1);

检查:
mysql> select * from mysql_query_rules;
+---------+--------+----------+------------+--------+-------------+------------+------------+--------+--------------+----------------------+----------------------+--------------+---------+-----------------+-----------------------+-----------+--------------------+---------------+-----------+---------+---------+-------+-------------------+----------------+------------------+-----------+--------+-------------+-----------+---------------------+-----+-------+------------+---------+
| rule_id | active | username | schemaname | flagIN | client_addr | proxy_addr | proxy_port | digest | match_digest | match_pattern        | negate_match_pattern | re_modifiers | flagOUT | replace_pattern | destination_hostgroup | cache_ttl | cache_empty_result | cache_timeout | reconnect | timeout | retries | delay | next_query_flagIN | mirror_flagOUT | mirror_hostgroup | error_msg | OK_msg | sticky_conn | multiplex | gtid_from_hostgroup | log | apply | attributes | comment |
+---------+--------+----------+------------+--------+-------------+------------+------------+--------+--------------+----------------------+----------------------+--------------+---------+-----------------+-----------------------+-----------+--------------------+---------------+-----------+---------+---------+-------+-------------------+----------------+------------------+-----------+--------+-------------+-----------+---------------------+-----+-------+------------+---------+
| 9       | 1      | NULL     | NULL       | 0      | NULL        | NULL       | NULL       | NULL   | NULL         | ^select.*for update$ | 0                    | CASELESS     | NULL    | NULL            | 10                    | NULL      | NULL               | NULL          | NULL      | NULL    | NULL    | NULL  | NULL              | NULL           | NULL             | NULL      | NULL   | NULL        | NULL      | NULL                | NULL | 1     |            | NULL    |
| 10      | 1      | NULL     | NULL       | 0      | NULL        | NULL       | NULL       | NULL   | NULL         | ^select              | 0                    | CASELESS     | NULL    | NULL            | 30                    | NULL      | NULL               | NULL          | NULL      | NULL    | NULL    | NULL  | NULL              | NULL           | NULL             | NULL      | NULL   | NULL        | NULL      | NULL                | NULL | 1     |            | NULL    |
+---------+--------+----------+------------+--------+-------------+------------+------------+--------+--------------+----------------------+----------------------+--------------+---------+-----------------+-----------------------+-----------+--------------------+---------------+-----------+---------+---------+-------+-------------------+----------------+------------------+-----------+--------+-------------+-----------+---------------------+-----+-------+------------+---------+
2 rows in set (0.00 sec)

  • 保存配置并载入内存生效
save mysql users to disk;
save mysql servers to disk;
save mysql query rules to disk;
save mysql variables to disk;
save admin variables to disk;
load mysql users to runtime;
load mysql servers to runtime;
load mysql query rules to runtime;
load mysql variables to runtime;
load admin variables to runtime;

检查:
mysql>  select * from runtime_mysql_servers;
+--------------+------------+------+-----------+--------+--------+-------------+-----------------+---------------------+---------+----------------+---------+
| hostgroup_id | hostname   | port | gtid_port | status | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment |
+--------------+------------+------+-----------+--------+--------+-------------+-----------------+---------------------+---------+----------------+---------+
| 10           | 10.10.6.49 | 4886 | 0         | ONLINE | 1      | 0           | 1000            | 0                   | 0       | 0              |         |
| 30           | 10.10.6.47 | 4886 | 0         | ONLINE | 1      | 0           | 1000            | 0                   | 0       | 0              |         |
| 30           | 10.10.6.48 | 4886 | 0         | ONLINE | 1      | 0           | 1000            | 0                   | 0       | 0              |         |
| 30           | 10.10.6.49 | 4886 | 0         | ONLINE | 1      | 0           | 1000            | 0                   | 0       | 0              |         |
+--------------+------------+------+-----------+--------+--------+-------------+-----------------+---------------------+---------+----------------+---------+
4 rows in set (0.01 sec)

配置完成。

  • 高可用路由验证: 相关登陆账户
#proxysql监控登录账户
mysql -uadmin -padmin -h 127.0.0.1 -P 6032 -A

#proxysql测试登录账户
mysql -uadmin2 -p'123456' -h127.0.0.1 -P6033 -A
  • 本文安装在 10.10.6.49, 测试登录账号进行验证:
create database d1;
create table d1.t1(c1 int, c2 varchar(10));
insert into d1.t1 values(1,"hello");
begin;insert into d1.t1 values(2,"world");select * from d1.t1;commit;
select * from d1.t1;
select * from d1.t1 for update;

有客户端,可使用数据库连接工具连接 10.10.6.49 6033 admin2 123456 ,创建库表,增删改查,验证
并对主节点 kill,验证其高可用路由;

=========================================================================================================


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