集群参数 enable_rereplication 介绍

多副本 OceanBase 集群中，通过 enable_rereplication 可以控制是否自动补全分区副本。

适用版本

OceanBase 数据库 V2.x、V3.x 版本。

参数介绍

在扩缩容场景或者发生宕机恢复后，如果集群参数 enable_rereplication = true，OceanBase 集群会自动补充缺失的副本。

使用示例

我们使用以下测试案例来验证 enable_rereplication 对补副本操作的影响。

参数 enable_rereplication = True 的测试

集群会自动补充缺失的副本。

1. 查询 enable_rereplication 设置为 true。

   obclient [CHUER]> show parameters like 'enable_rereplication';
   

   +-------+----------+-------------+----------+----------------------+-----------+-------+----------------------------------------------------------------------------------------------------------+--------------+---------+---------+-------------------+
   | ZONE  | SVR_TYPE | SVR_IP      | SVR_PORT | NAME                 | DATA_TYPE | VALUE | INFO                                                                                                     | SECTION      | SCOPE   | SOURCE  | EDIT_LEVEL        |
   +-------+----------+-------------+----------+----------------------+-----------+-------+----------------------------------------------------------------------------------------------------------+--------------+---------+---------+-------------------+
   | zone2 | observer | 172.xx.x.xx |     2882 | enable_rereplication | NULL      | True  | specifies whether the partition auto-replication is turned on. Value:  True:turned on  False: turned off | LOAD_BALANCE | CLUSTER | DEFAULT | DYNAMIC_EFFECTIVE |
   | zone1 | observer | 172.xx.x.xx |     2882 | enable_rereplication | NULL      | True  | specifies whether the partition auto-replication is turned on. Value:  True:turned on  False: turned off | LOAD_BALANCE | CLUSTER | DEFAULT | DYNAMIC_EFFECTIVE |
   | zone3 | observer | 172.xx.x.xx |     2882 | enable_rereplication | NULL      | True  | specifies whether the partition auto-replication is turned on. Value:  True:turned on  False: turned off | LOAD_BALANCE | CLUSTER | DEFAULT | DYNAMIC_EFFECTIVE |
   +-------+----------+-------------+----------+----------------------+-----------+-------+----------------------------------------------------------------------------------------------------------+--------------+---------+---------+-------------------+
   3 rows in set (0.108 sec)
   

   obclient [oceanbase]> select zone,name,value,info from __all_zone where name in ('status','zone_type');
   

   +-------+-----------+-------+-----------+
   | zone  | name      | value | info      |
   +-------+-----------+-------+-----------+
   | zone1 | status    |     2 | ACTIVE    |
   | zone1 | zone_type |     0 | ReadWrite |
   | zone2 | status    |     2 | ACTIVE    |
   | zone2 | zone_type |     0 | ReadWrite |
   | zone3 | status    |     1 | INACTIVE  |
   | zone3 | zone_type |     0 | ReadWrite |
   +-------+-----------+-------+-----------+
   6 rows in set (0.09 sec)
   

   obclient [CHUER]> create table t1 (id int ,col varchar2(10));
   Query OK, 0 rows affected (0.276 sec)
   

2. 查询表分区副本情况。

   obclient [oceanbase]> select t.tenant_name,db.database_name ,tb.table_name, p.partition_id ,p.zone  
       from gv$partition p,__all_virtual_table tb,__all_virtual_database db,__all_tenant t
       where t.tenant_id=db.tenant_id and t.tenant_id=tb.tenant_id and t.tenant_id=p.tenant_id
           and db.database_id=tb.database_id and tb.table_id=p.table_id 
       and tenant_name='t_oracle' 
       and database_name='CHUER'
       and tb.table_name='T1'
       ;
   

   +-------------+---------------+------------+--------------+-------+
   | tenant_name | database_name | table_name | partition_id | zone  |
   +-------------+---------------+------------+--------------+-------+
   | t_oracle    | CHUER         | T1         |            0 | zone2 |
   | t_oracle    | CHUER         | T1         |            0 | zone1 |
   +-------------+---------------+------------+--------------+-------+
   2 rows in set (0.29 sec)
   

3. 启动 zone 后。

   obclient [oceanbase]> select zone,name,value,info from __all_zone where name in ('status','zone_type');
   

   +-------+-----------+-------+-----------+
   | zone  | name      | value | info      |
   +-------+-----------+-------+-----------+
   | zone1 | status    |     2 | ACTIVE    |
   | zone1 | zone_type |     0 | ReadWrite |
   | zone2 | status    |     2 | ACTIVE    |
   | zone2 | zone_type |     0 | ReadWrite |
   | zone3 | status    |     2 | ACTIVE    |
   | zone3 | zone_type |     0 | ReadWrite |
   +-------+-----------+-------+-----------+
   6 rows in set (0.00 sec)
   

   obclient [oceanbase]> select gmt_create,gmt_modified,svr_ip,zone,with_rootserver,status from   __all_server;
   

   +----------------------------+----------------------------+-------------+-------+-----------------+--------+
   | gmt_create                 | gmt_modified               | svr_ip      | zone  | with_rootserver | status |
   +----------------------------+----------------------------+-------------+-------+-----------------+--------+
   | 2023-06-15 01:55:17.788504 | 2023-07-03 16:01:57.250198 | 172.xx.x.xx | zone1 |               1 | active |
   | 2023-06-15 01:55:17.722023 | 2023-07-03 16:01:57.260188 | 172.xx.x.xx | zone2 |               0 | active |
   | 2023-06-15 01:55:17.712516 | 2023-07-21 12:58:20.312848 | 172.xx.x.xx | zone3 |               0 | active |
   +----------------------------+----------------------------+-------------+-------+-----------------+--------+
   3 rows in set (0.01 sec)
   

4. 查询 zone 恢复后的副本情况，副本自动补全。

   obclient [oceanbase]> select t.tenant_name,db.database_name ,tb.table_name, p.partition_id ,p.zone  
       -> from gv$partition p,__all_virtual_table tb,__all_virtual_database db,__all_tenant t
       ->   where t.tenant_id=db.tenant_id and t.tenant_id=tb.tenant_id and t.tenant_id=p.tenant_id
       ->     and db.database_id=tb.database_id and tb.table_id=p.table_id 
       -> and tenant_name='t_oracle' 
       -> and database_name='CHUER'
       -> and tb.table_name='T1'
       -> ;
   

   +-------------+---------------+------------+--------------+-------+
   | tenant_name | database_name | table_name | partition_id | zone  |
   +-------------+---------------+------------+--------------+-------+
   | t_oracle    | CHUER         | T1         |            0 | zone3 |
   | t_oracle    | CHUER         | T1         |            0 | zone2 |
   | t_oracle    | CHUER         | T1         |            0 | zone1 |
   +-------------+---------------+------------+--------------+-------+
   3 rows in set (0.32 sec)
   

参数 enable_rereplication = False 的测试

集群不会自动补充副本。重新设置为 true 后，副本自动补全。

1. 查询 enable_rereplication 设置为 false。

   obclient [CHUER]> show parameters like 'enable_rereplication';
   

   +-------+----------+-------------+----------+----------------------+-----------+-------+----------------------------------------------------------------------------------------------------------+--------------+---------+---------+-------------------+
   | ZONE  | SVR_TYPE | SVR_IP      | SVR_PORT | NAME                 | DATA_TYPE | VALUE | INFO                                                                                                     | SECTION      | SCOPE   | SOURCE  | EDIT_LEVEL        |
   +-------+----------+-------------+----------+----------------------+-----------+-------+----------------------------------------------------------------------------------------------------------+--------------+---------+---------+-------------------+
   | zone2 | observer | 172.xx.x.xx |     2882 | enable_rereplication | NULL      | False | specifies whether the partition auto-replication is turned on. Value:  True:turned on  False: turned off | LOAD_BALANCE | CLUSTER | DEFAULT | DYNAMIC_EFFECTIVE |
   | zone3 | observer | 172.xx.x.xx |     2882 | enable_rereplication | NULL      | False | specifies whether the partition auto-replication is turned on. Value:  True:turned on  False: turned off | LOAD_BALANCE | CLUSTER | DEFAULT | DYNAMIC_EFFECTIVE |
   | zone1 | observer | 172.xx.x.xx |     2882 | enable_rereplication | NULL      | False | specifies whether the partition auto-replication is turned on. Value:  True:turned on  False: turned off | LOAD_BALANCE | CLUSTER | DEFAULT | DYNAMIC_EFFECTIVE |
   +-------+----------+-------------+----------+----------------------+-----------+-------+----------------------------------------------------------------------------------------------------------+--------------+---------+---------+-------------------+
   3 rows in set (0.049 sec)
   

2. 停止 zone。

   obclient [oceanbase]>   select zone,name,value,info from __all_zone where name in ('status','zone_type');
   

   +-------+-----------+-------+-----------+
   | zone  | name      | value | info      |
   +-------+-----------+-------+-----------+
   | zone1 | status    |     2 | ACTIVE    |
   | zone1 | zone_type |     0 | ReadWrite |
   | zone2 | status    |     2 | ACTIVE    |
   | zone2 | zone_type |     0 | ReadWrite |
   | zone3 | status    |     1 | INACTIVE  |
   | zone3 | zone_type |     0 | ReadWrite |
   +-------+-----------+-------+-----------+
   6 rows in set (0.00 sec)
   

3. 查询副本情况。

   obclient [oceanbase]> select t.tenant_name,db.database_name ,tb.table_name, p.partition_id ,p.zone  
       ->      from gv$partition p,__all_virtual_table tb,__all_virtual_database db,__all_tenant t
       ->      where t.tenant_id=db.tenant_id and t.tenant_id=tb.tenant_id and t.tenant_id=p.tenant_id
       ->      and db.database_id=tb.database_id and tb.table_id=p.table_id 
       ->      and tenant_name='t_oracle' 
       ->      and database_name='CHUER'
       ->      and tb.table_name='T2'
       ->      ;
   

   +-------------+---------------+------------+--------------+-------+
   | tenant_name | database_name | table_name | partition_id | zone  |
   +-------------+---------------+------------+--------------+-------+
   | t_oracle    | CHUER         | T2         |            0 | zone2 |
   | t_oracle    | CHUER         | T2         |            0 | zone1 |
   +-------------+---------------+------------+--------------+-------+
   2 rows in set (0.31 sec)
   

4. 启用 zone。

   obclient [oceanbase]>  select gmt_create,gmt_modified,svr_ip,zone,with_rootserver,status from __all_server;
   

   +----------------------------+----------------------------+-------------+-------+-----------------+--------+
   | gmt_create                 | gmt_modified               | svr_ip      | zone  | with_rootserver | status |
   +----------------------------+----------------------------+-------------+-------+-----------------+--------+
   | 2023-06-15 01:55:17.788504 | 2023-07-03 16:01:57.250198 | 172.xx.x.xx | zone1 |               1 | active |
   | 2023-06-15 01:55:17.722023 | 2023-07-03 16:01:57.260188 | 172.xx.x.xx | zone2 |               0 | active |
   | 2023-06-15 01:55:17.712516 | 2023-07-21 14:21:56.645521 | 172.xx.x.xx | zone3 |               0 | active |
   +----------------------------+----------------------------+-------------+-------+-----------------+--------+
   3 rows in set (0.01 sec)
   

   obclient [oceanbase]> select zone,name,value,info from __all_zone where name in ('status','zone_type');
   

   +-------+-----------+-------+-----------+
   | zone  | name      | value | info      |
   +-------+-----------+-------+-----------+
   | zone1 | status    |     2 | ACTIVE    |
   | zone1 | zone_type |     0 | ReadWrite |
   | zone2 | status    |     2 | ACTIVE    |
   | zone2 | zone_type |     0 | ReadWrite |
   | zone3 | status    |     2 | ACTIVE    |
   | zone3 | zone_type |     0 | ReadWrite |
   +-------+-----------+-------+-----------+
   6 rows in set (0.01 sec)
   

5. 查询 zone 恢复后的副本情况，副本不会补全。

   obclient [oceanbase]> select t.tenant_name,db.database_name ,tb.table_name, p.partition_id ,p.zone  
       ->      from gv$partition p,__all_virtual_table tb,__all_virtual_database db,__all_tenant t
       ->      where t.tenant_id=db.tenant_id and t.tenant_id=tb.tenant_id and t.tenant_id=p.tenant_id
       ->      and db.database_id=tb.database_id and tb.table_id=p.table_id 
       ->      and tenant_name='t_oracle' 
       ->      and database_name='CHUER'
       ->      and tb.table_name='T2'
       ->      ;
   

   +-------------+---------------+------------+--------------+-------+
   | tenant_name | database_name | table_name | partition_id | zone  |
   +-------------+---------------+------------+--------------+-------+
   | t_oracle    | CHUER         | T2         |            0 | zone2 |
   | t_oracle    | CHUER         | T2         |            0 | zone1 |
   +-------------+---------------+------------+--------------+-------+
   2 rows in set (0.29 sec)
   

6. 重新设置为 true 后，副本自动补全。

   obclient [oceanbase]>  alter system set enable_rereplication=true;
   Query OK, 0 rows affected (0.08 sec)
   

   obclient [oceanbase]> select t.tenant_name,db.database_name ,tb.table_name, p.partition_id ,p.zone from gv$partition p,__all_virtual_table tb,__all_virtual_database db,__all_tenant t where t.tenant_id=db.tenant_id and t.tenant_id=tb.tenant_id and t.tenant_id=p.tenant_id and db.database_id=tb.database_id and tb.table_id=p.table_id and tenant_name='t_oracle' and database_name='CHUER' and tb.table_name='T2';
   

   +-------------+---------------+------------+--------------+-------+
   | tenant_name | database_name | table_name | partition_id | zone  |
   +-------------+---------------+------------+--------------+-------+
   | t_oracle    | CHUER         | T2         |            0 | zone3 |
   | t_oracle    | CHUER         | T2         |            0 | zone2 |
   | t_oracle    | CHUER         | T2         |            0 | zone1 |
   +-------------+---------------+------------+--------------+-------+
   3 rows in set (0.35 sec)