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OceanBase租户扩缩容的三种方法

news 来源：原创 2025/5/4 7:21:41

OceanBase租户扩缩容的三种方法

租户扩缩容：调整Unit Config
- 场景一：租户配置了独立的资源规格
- 场景二：多个租户使用了相同的资源规格
租户扩缩容：调整Unit Number
- 设置租户内的负载均衡策略
- 修改Unit Number实现扩缩容
租户扩缩容：调整Primary Zone
- 增加Primary Zone
- 减少Primary Zone

OceanBase V4.2.5

租户扩容可以提升计算能力和存储容量，OceanBase数据库提供了以下两种途径来实现扩缩容：

提高单节点的服务能力：即调大租户资源池使用的资源规格（unit config）。
增加服务节点的数量：可以分为增加资源单元（unit number）或者增加Primary Zone。

缩容是扩容的反操作，本质上是降低租户的服务能力，包括计算能力和存储容量。可以是调小资源规格，从而降低单节点的服务能力；也可以是通过减少服务节点，包括减少Primary Zone个数和减少Unit Number。

租户扩缩容：调整Unit Config

⚠️ 注意事项

在扩容前，如果有租户被删除，建议与租户对应的资源池也一并删除，以便释放资源。
进行租户缩容前，建议进行一轮转储以便释放租户正在使用的内存。
在调大资源规格时，无论是通过修改资源配置还是切换资源配置，调整后的资源总量都必须满足以下要求：

sum(min_cpu) <= CPU_CAPACITY
sum(max_cpu) <= CPU_CAPACITY * resource_hard_limit
sum(memory_size) <= MEM_CAPACITY
sum(log_disk_size) <= LOG_DISK_CAPACITY

其中，CPU_CAPACITY、MEM_CAPACITY、LOG_DISK_CAPACITY分别表示CPU总量、内存总量和日志盘总容量。resource_hard_limit是一个配置项的值。在分配Unit时，系统会根据配置项resource_hard_limit的值来分配CPU资源。该配置项的默认值为100，表示不允许超卖，取值范围为[100,10000]。

登录到集群SYS租户，这些容量指标的查看方式如下：

--查询资源上限
select svr_ip,zone,cpu_capacity,cpu_assigned,mem_capacity,mem_assigned,log_disk_capacity,log_disk_assigned,
data_disk_capacity,data_disk_allocated from oceanbase.GV$OB_SERVERS;select svr_ip,zone,tenant_id,scope,section,name,value,edit_level,default_value 
from oceanbase.gv$ob_parameters where name='resource_hard_limit';--查询资源规格
select unit_config_id,name,max_cpu,min_cpu,memory_size,log_disk_size from oceanbase.dba_ob_unit_configs;--查询租户资源分配
select unit_id,tenant_id,resource_pool_id,unit_config_id,max_cpu,min_cpu,memory_size,log_disk_size from oceanbase.dba_ob_units;
select svr_ip,unit_id,tenant_id,max_cpu,min_cpu,memory_size,log_disk_size from gv$ob_units;

📖 在通过调大和调小租户资源规格进行扩容和缩容时，有以下两种场景：

当前租户配置了独立的资源规格，可以直接修改租户的资源规格。
多个租户使用了相同的资源规格，需要切换租户的资源规格。

登录SYS租户管理员，获取租户所使用的资源规格ID：

obclient(root@sys)[oceanbase]> select a.tenant_name, b.unit_config_id from oceanbase.dba_ob_tenants a,oceanbase.dba_ob_resource_pools b where b.tenant_id=a.tenant_id;
+-------------+----------------+
| tenant_name | unit_config_id |
+-------------+----------------+
| sys         |              1 |
| tpcc        |           1001 |
| mysql_t1    |           1002 |
| mysql_t2    |           1002 |
+-------------+----------------+

上面的查询结果中，tpcc租户使用了独立的资源规格，mysql_t1和mysql_t2使用了相同的资源规格。

场景一：租户配置了独立的资源规格

以tpcc租户为例。

登录集群SYS租户，查询待操作租户所使用的UNIT_CONFIG_ID：

obclient(root@sys)[oceanbase]> select a.tenant_name, b.unit_config_id from oceanbase.dba_ob_tenants a,oceanbase.dba_ob_resource_pools b where b.tenant_id=a.tenant_id;
+-------------+----------------+
| tenant_name | unit_config_id |
+-------------+----------------+
| sys         |              1 |
| tpcc        |           1001 |
| mysql_t1    |           1002 |
| mysql_t2    |           1002 |
+-------------+----------------+
4 rows in set (0.021 sec)

查询待操作租户的资源规格详情。

obclient(root@sys)[oceanbase]> select * from oceanbase.dba_ob_unit_configs where unit_config_id='1001';
+----------------+-----------+----------------------------+----------------------------+---------+---------+--------------+---------------+----------+----------+-------------+
| UNIT_CONFIG_ID | NAME      | CREATE_TIME                | MODIFY_TIME                | MAX_CPU | MIN_CPU | MEMORY_SIZE  | LOG_DISK_SIZE | MAX_IOPS | MIN_IOPS | IOPS_WEIGHT |
+----------------+-----------+----------------------------+----------------------------+---------+---------+--------------+---------------+----------+----------+-------------+
|           1001 | tpcc_unit | 2025-04-16 10:22:22.470219 | 2025-04-16 10:22:22.470219 |      24 |      24 | 200789721088 |  708132732928 |    10000 |    10000 |          36 |
+----------------+-----------+----------------------------+----------------------------+---------+---------+--------------+---------------+----------+----------+-------------+
1 row in set (0.011 sec)

检查节点资源上限。

select svr_ip,zone,cpu_capacity,cpu_assigned,
round(mem_capacity/1024/1024/1024,2) as mem_capacity_gb,
round(mem_assigned/1024/1024/1024,2) as mem_assigned_gb,
round(log_disk_capacity/1024/1024/1024,2) as log_disk_capacity_gb,
round(log_disk_assigned/1024/1024/1024,2) as log_disk_assigned_gb, 
round(data_disk_capacity/1024/1024/1024,2) as data_disk_capacity_gb,
round(data_disk_allocated/1024/1024/1024,2) as data_disk_allocated_gb 
from oceanbase.GV$OB_SERVERS;select svr_ip,unit_id,tenant_id,max_cpu,min_cpu,
round(memory_size/1024/1024/1024,2) as memory_size_gb,
round(log_disk_size/1024/1024/1024,2) as log_disk_size_gb 
from gv$ob_units;

调大（或调小）资源规格。

--调小资源规格
alter resource unit tpcc_unit max_cpu 8, min_cpu 8, memory_size '20g', log_disk_size '60g';--调大资源规格
alter resource unit tpcc_unit max_cpu 28, min_cpu 28, memory_size '120g', log_disk_size '360g';

确认是否修改成功。

obclient(root@sys)[oceanbase]> select * from oceanbase.dba_ob_unit_configs where unit_config_id='1001';
+----------------+-----------+----------------------------+----------------------------+---------+---------+--------------+---------------+----------+----------+-------------+
| UNIT_CONFIG_ID | NAME      | CREATE_TIME                | MODIFY_TIME                | MAX_CPU | MIN_CPU | MEMORY_SIZE  | LOG_DISK_SIZE | MAX_IOPS | MIN_IOPS | IOPS_WEIGHT |
+----------------+-----------+----------------------------+----------------------------+---------+---------+--------------+---------------+----------+----------+-------------+
|           1001 | tpcc_unit | 2025-04-16 10:22:22.470219 | 2025-04-26 12:04:15.664243 |      28 |      28 | 128849018880 |  386547056640 |    10000 |    10000 |          36 |
+----------------+-----------+----------------------------+----------------------------+---------+---------+--------------+---------------+----------+----------+-------------+
1 row in set (0.000 sec)

场景二：多个租户使用了相同的资源规格

多个租户共用了同一个资源规格时，不能通过简单的调大和调小资源规格来实现租户的扩容和缩容。因为一旦修改，将导致使用相同资源规格的所有租户同时进行了扩容或缩容。此场景下，需要先创建独立的资源规格后，再为租户切换资源规格。

以mysql_t2租户为例。

登录集群SYS租户，查询待操作租户所使用的UNIT_CONFIG_ID和RESOURCE_POOL_NAME。

obclient(root@sys)[oceanbase]> select a.tenant_name, b.name resource_pool_name, b.unit_config_id  from oceanbase.dba_ob_tenants a,oceanbase.dba_ob_resource_pools b where b.tenant_id=a.tenant_id;
+-------------+--------------------+----------------+
| tenant_name | resource_pool_name | unit_config_id |
+-------------+--------------------+----------------+
| sys         | sys_pool           |              1 |
| tpcc        | tpcc_pool          |           1001 |
| mysql_t1    | pool_mysql_s1      |           1002 |
| mysql_t2    | pool_mysql_s2      |           1002 |
+-------------+--------------------+----------------+
4 rows in set (0.008 sec)

查询待操作租户的资源规格详情。

obclient(root@sys)[oceanbase]> select * from oceanbase.dba_ob_unit_configs where unit_config_id='1002';
+----------------+---------------+----------------------------+----------------------------+---------+---------+-------------+---------------+---------------------+---------------------+-------------+
| UNIT_CONFIG_ID | NAME          | CREATE_TIME                | MODIFY_TIME                | MAX_CPU | MIN_CPU | MEMORY_SIZE | LOG_DISK_SIZE | MAX_IOPS            | MIN_IOPS            | IOPS_WEIGHT |
+----------------+---------------+----------------------------+----------------------------+---------+---------+-------------+---------------+---------------------+---------------------+-------------+
|           1002 | unit_mysql_s1 | 2025-04-26 11:18:04.887209 | 2025-04-26 12:06:13.453403 |       1 |       1 |  2147483648 |    6442450944 | 9223372036854775807 | 9223372036854775807 |           1 |
+----------------+---------------+----------------------------+----------------------------+---------+---------+-------------+---------------+---------------------+---------------------+-------------+
1 row in set (0.000 sec)

检查节点资源上限。

select svr_ip,zone,cpu_capacity,cpu_assigned,
round(mem_capacity/1024/1024/1024,2) as mem_capacity_gb,
round(mem_assigned/1024/1024/1024,2) as mem_assigned_gb,
round(log_disk_capacity/1024/1024/1024,2) as log_disk_capacity_gb,
round(log_disk_assigned/1024/1024/1024,2) as log_disk_assigned_gb, 
round(data_disk_capacity/1024/1024/1024,2) as data_disk_capacity_gb,
round(data_disk_allocated/1024/1024/1024,2) as data_disk_allocated_gb 
from oceanbase.GV$OB_SERVERS;select svr_ip,unit_id,tenant_id,max_cpu,min_cpu,
round(memory_size/1024/1024/1024,2) as memory_size_gb,
round(log_disk_size/1024/1024/1024,2) as log_disk_size_gb 
from gv$ob_units;

创建一个独立的新资源规格，新资源规格各项资源值为待修改的目标值。

select unit_config_id,name,max_cpu,min_cpu,
round(memory_size/1024/1024/1024,2) as memory_size_gb,
round(log_disk_size/1024/1024/1024,2) as log_disk_size_gb 
from oceanbase.dba_ob_unit_configs;create resource unit unit_mysql_s2 max_cpu = 2, min_cpu = 2, memory_size = '2g',log_disk_size = '6g';

调整待操作租户的资源池使用新资源规格。

select resource_pool_id,a.name pool_name,tenant_id,unit_count,a.unit_config_id,b.name unit_config_name,zone_list 
from dba_ob_resource_pools a, dba_ob_unit_configs b where a.unit_config_id=b.unit_config_id;alter resource pool pool_mysql_s2 unit='unit_mysql_s2';

查询租户当前的资源规格，确认是否修改成功。

obclient(root@sys)[oceanbase]> select a.tenant_name, b.name resource_pool_name, b.unit_config_id  from oceanbase.dba_ob_tenants a,oceanbase.dba_ob_resource_pools b where b.tenant_id=a.tenant_id;
+-------------+--------------------+----------------+
| tenant_name | resource_pool_name | unit_config_id |
+-------------+--------------------+----------------+
| sys         | sys_pool           |              1 |
| tpcc        | tpcc_pool          |           1001 |
| mysql_t1    | pool_mysql_s1      |           1002 |
| mysql_t2    | pool_mysql_s2      |           1003 |
+-------------+--------------------+----------------+
4 rows in set (0.008 sec)obclient(root@sys)[oceanbase]> select * from oceanbase.dba_ob_unit_configs where unit_config_id='1003';
+----------------+---------------+----------------------------+----------------------------+---------+---------+-------------+---------------+---------------------+---------------------+-------------+
| UNIT_CONFIG_ID | NAME          | CREATE_TIME                | MODIFY_TIME                | MAX_CPU | MIN_CPU | MEMORY_SIZE | LOG_DISK_SIZE | MAX_IOPS            | MIN_IOPS            | IOPS_WEIGHT |
+----------------+---------------+----------------------------+----------------------------+---------+---------+-------------+---------------+---------------------+---------------------+-------------+
|           1003 | unit_mysql_s2 | 2025-04-26 12:15:23.678828 | 2025-04-26 12:15:23.678828 |       2 |       2 |  2147483648 |    6442450944 | 9223372036854775807 | 9223372036854775807 |           2 |
+----------------+---------------+----------------------------+----------------------------+---------+---------+-------------+---------------+---------------------+---------------------+-------------+
1 row in set (0.000 sec)

租户扩缩容：调整Unit Number

从OB V4.0.0版本开始，OceanBase数据库要求租户内每个Zone的Unit个数必须保持一致。为了方便统一管理各个Zone的Unit，系统引入了Unit Group机制，即不同Zone之间相同编号（UNIT_GROUP_ID）的Unit属于同一个Unit Group。调大或调小Unit Number本质上是以Unit Group为单位创建和删除Unit。

⚠️由于一个租户在一个OB节点只能同时存在一个Unit。因此调整Unit Number扩容租户不适用于单机部署模式。单机模式查下扩容Unit Number会收到下面的报错：

ERROR 4734 (HY000): zone 'zone1' server not enough to hold 1 new unit, please check zone valid servers

⚠️ 注意事项

在扩容前，如果有租户被删除，建议与租户对应的资源池也一并删除，以便释放资源。
进行租户缩容前，建议进行一轮转储以便释放租户正在使用的内存。
在进行租户的扩容和缩容操作前，设置租户内的负载均衡策略。

设置租户内的负载均衡策略

租户内的负载均衡策略由租户级配置项enable_rebalance和enable_transfer共同控制。

enable_rebalance在系统租户下配置可用于控制是否进行租户间的负载均衡；在用户租户下配置可用于控制是否进行租户内均衡。默认值为true，可动态修改。
enable_transfer用于控制是否允许在租户内进行Transfer。默认值为true，可动态修改。配置项enable_rebalance=false时此配置项无效。
- enable_rebalance=false时，系统不会进行自动负载均衡。
- enable_rebalance=true且enable_transfer=true时，在进行租户扩缩容操作时，系统会自动调整分区分布，实现负载均衡。
- enable_rebalance=true且enable_transfer=false时，在进行租户扩缩容操作时，系统不能发起 Transfe操作，只能通过日志流迁移实现有限的均衡。

检查租户的负载均衡配置：

obclient(root@sys)[oceanbase]> 
select svr_ip,zone,tenant_id,scope,section,name,value,edit_level,default_value   
from oceanbase.gv$ob_parameters where name in ('enable_rebalance','enable_transfer');+-------------+-------+-----------+--------+--------------+------------------+-------+-------------------+---------------+
| svr_ip      | zone  | tenant_id | scope  | section      | name             | value | edit_level        | default_value |
+-------------+-------+-----------+--------+--------------+------------------+-------+-------------------+---------------+
| 172.xx.x.xx | zone1 |         1 | TENANT | LOAD_BALANCE | enable_transfer  | True  | DYNAMIC_EFFECTIVE | True          |
| 172.xx.x.xx | zone1 |         1 | TENANT | LOAD_BALANCE | enable_rebalance | True  | DYNAMIC_EFFECTIVE | True          |
| 172.xx.x.xx | zone1 |      1001 | TENANT | LOAD_BALANCE | enable_transfer  | True  | DYNAMIC_EFFECTIVE | True          |
| 172.xx.x.xx | zone1 |      1001 | TENANT | LOAD_BALANCE | enable_rebalance | True  | DYNAMIC_EFFECTIVE | True          |
| 172.xx.x.xx | zone1 |      1002 | TENANT | LOAD_BALANCE | enable_transfer  | True  | DYNAMIC_EFFECTIVE | True          |
| 172.xx.x.xx | zone1 |      1002 | TENANT | LOAD_BALANCE | enable_rebalance | True  | DYNAMIC_EFFECTIVE | True          |
| 172.xx.x.xx | zone1 |      1003 | TENANT | LOAD_BALANCE | enable_transfer  | True  | DYNAMIC_EFFECTIVE | True          |
| 172.xx.x.xx | zone1 |      1003 | TENANT | LOAD_BALANCE | enable_rebalance | True  | DYNAMIC_EFFECTIVE | True          |
...

开启单个用户租户的负载均衡：

ALTER SYSTEM SET enable_rebalance = true TENANT = 'mysql_t1';
ALTER SYSTEM SET enable_transfer = true TENANT = 'mysql_t1';

开启所有租户的负载均衡：

ALTER SYSTEM SET enable_rebalance = true TENANT = all_user;
ALTER SYSTEM SET enable_transfer = true TENANT = all_user;

修改Unit Number实现扩缩容

登录SYS租户，查看要扩缩容租户的tenant_id信息。

select * from oceanbase.dba_ob_tenants where tenant_name = 'mysql_t1';

查看目标租户的所有Unit和Unit Group信息。

select * from oceanbase.dba_ob_units where tenant_id = 1004;

检查OB节点的数量和zone信息。

select svr_ip,svr_port,zone from oceanbase.gv$ob_servers;

修改目标租户的Unit Number。

如果是租户扩容，调大Unit Number即可（不要超过OB节点数）；如果是租户缩容，调小Unit Number即可。

ALTER RESOURCE TENANT mysql_t1 UNIT_NUM = 2;

缩容时可以指定要删除的UNIT_GROUP。

ALTER RESOURCE TENANT mysql_t1 UNIT_NUM = 1 DELETE UNIT_GROUP =(1003);

查看Unit Number变更任务的执行状态。

select * from oceanbase.dba_ob_tenant_jobs where job_type='ALTER_RESOURCE_TENANT_UNIT_NUM' and tenant_id=1004;

字段START_TIME是任务发起的时间；
字段EXTRA_INFO记录了变更前后的Unit Number数。
字段JOB_STATUS的值为SUCCESS时，表示修改Unit Number的任务执行成功。

确认修改后的Unit。

select * from oceanbase.dba_ob_units where tenant_id = 1004;

租户扩缩容：调整Primary Zone

通过修改Primary Zone，可以横向增加或减少计算节点，达到租户总服务能力的提升或降低，实现租户的扩容或缩容。

调整Primary Zone前，需要设置租户内的负载均衡策略。租户内的负载均衡策略由租户级配置项enable_rebalance和enable_transfer共同控制。

配置项enable_rebalance和enable_transfer的介绍，请参考上文的《租户扩缩容：调整Unit Number》部分。

增加Primary Zone

登录到SYS租户，查询要扩容租户的tenant_id和primazy_zone信息。

obclient(root@sys)[oceanbase]> 
select tenant_id, tenant_name, primary_zone from oceanbase.dba_ob_tenants where tenant_name = 'tpcc';+-----------+-------------+--------------+
| TENANT_ID | TENANT_NAME | PRIMARY_ZONE |
+-----------+-------------+--------------+
|      1004 | tpcc        | zone1;zone2  |
+-----------+-------------+--------------+
1 row in set

查询目标租户当前日志流Leader副本位置的分布信息。

select tenant_id, ls_id, svr_ip, svr_port, zone, role, replica_type 
from oceanbase.cdb_ob_ls_locations where tenant_id = 1004 and ls_id != 1 and role = 'LEADER';+-----------+-------+---------------+----------+--------+--------+--------------+
| TENANT_ID | LS_ID | SVR_IP        | SVR_PORT | ZONE   | ROLE   | REPLICA_TYPE |
+-----------+-------+---------------+----------+--------+--------+--------------+
|      1004 |  1001 | 172.xx.xxx.xx |    2882  |  zone1 | LEADER | FULL         |
|      1004 |  1012 | 172.xx.xxx.xx |    2882  |  zone1 | LEADER | FULL         |
+-----------+-------+---------------+----------+--------+--------+--------------+
2 rows in set

修改目标租户的primary_zone属性，第一优先级Zone的个数从1调整为2。

ALTER TENANT tpcc PRIMARY_ZONE='zone1,zone2';

查看增加Primary Zone任务的执行状态。

select * from oceanbase.dba_ob_tenant_jobs where job_type='ALTER_TENANT_PRIMARY_ZONE' and tenant_id = 1004;+--------+---------------------------+------------+-------------+----------+----------------------------+----------------------------+-----------+--------------------------------------------------+-------------+----------------+-------------+
| JOB_ID | JOB_TYPE                  | JOB_STATUS | RESULT_CODE | PROGRESS | START_TIME                 | MODIFY_TIME                | TENANT_ID | SQL_TEXT                                         | EXTRA_INFO  | RS_SVR_IP      | RS_SVR_PORT |
+--------+---------------------------+------------+-------------+----------+----------------------------+----------------------------+-----------+--------------------------------------------------+-------------+----------------+-------------+
|      4 | ALTER_TENANT_PRIMARY_ZONE | SUCCESS    |           0 |      100 | 2024-12-18 17:26:00.069089 | 2024-12-18 17:26:20.919021 |      1004 | ALTER TENANT tpcc PRIMARY_ZONE='zone1,zone2'     | zone1;zone2 | 172.xx.xxx.xx  |       2882  |
+--------+---------------------------+------------+-------------+----------+----------------------------+----------------------------+-----------+--------------------------------------------------+-------------+----------------+-------------+
1 row in set

查询目标租户信息，确认PRIMARY_ZONE属性修改成功，第一优先级由zone1变更为zone1,zone2。

select primary_zone from oceanbase.dba_ob_tenants where tenant_id = 1004;+--------------+
| PRIMARY_ZONE |
+--------------+
| zone1,zone2  |
+--------------+
1 row in set

再次查询目标租户日志流Leader副本位置的分布信息。

select tenant_id, ls_id, svr_ip, svr_port, zone, role, replica_type 
from oceanbase.cdb_ob_ls_locations where tenant_id = 1004 and ls_id != 1 and role = 'LEADER';+-----------+-------+---------------+----------+-------+--------+--------------+
| TENANT_ID | LS_ID | SVR_IP        | SVR_PORT | ZONE  | ROLE   | REPLICA_TYPE |
+-----------+-------+---------------+----------+-------+--------+--------------+
|      1004 |  1001 | 172.xx.xxx.xx |    2882  | zone1 | LEADER | FULL         |
|      1004 |  1012 | 172.xx.xxx.xx |    2882  | zone1 | LEADER | FULL         |
|      1004 |  1013 | 172.xx.xxx.xx |    2882  | zone2 | LEADER | FULL         |
|      1004 |  1014 | 172.xx.xxx.xx |    2882  | zone2 | LEADER | FULL         |
+-----------+-------+---------------+----------+-------+--------+--------------+
4 rows in set

减少Primary Zone

登录到SYS租户，查询要缩容租户的tenant_id和primazy_zone信息。

select tenant_id, tenant_name, primary_zone from oceanbase.dba_ob_tenants where tenant_name = 'tpcc';+-----------+-------------+--------------+
| TENANT_ID | TENANT_NAME | PRIMARY_ZONE |
+-----------+-------------+--------------+
|      1004 | tpcc        | zone1,zone2  |
+-----------+-------------+--------------+
1 row in set

查询目标租户当前日志流Leader副本位置的分布信息。

select tenant_id, ls_id, svr_ip, svr_port, zone, role, replica_type 
from oceanbase.cdb_ob_ls_locations where tenant_id = 1004 and ls_id != 1 and role = 'LEADER';+-----------+-------+---------------+----------+-------+--------+--------------+
| TENANT_ID | LS_ID | SVR_IP        | SVR_PORT | ZONE  | ROLE   | REPLICA_TYPE |
+-----------+-------+---------------+----------+-------+--------+--------------+
|      1004 |  1001 | 172.xx.xxx.xx |    2882  | zone1 | LEADER | FULL         |
|      1004 |  1012 | 172.xx.xxx.xx |    2882  | zone1 | LEADER | FULL         |
|      1004 |  1013 | 172.xx.xxx.xx |    2882  | zone2 | LEADER | FULL         |
|      1004 |  1014 | 172.xx.xxx.xx |    2882  | zone2 | LEADER | FULL         |
+-----------+-------+---------------+----------+-------+--------+--------------+
4 rows in set

修改目标租户的primary_zone属性，第一优先级Zone的个数从2调整为1。

ALTER TENANT tpcc PRIMARY_ZONE='zone1;zone2';

查看减少Primary Zone任务的执行状态。

select * from oceanbase.dba_ob_tenant_jobs where job_type='ALTER_TENANT_PRIMARY_ZONE' and tenant_id = 1004;

查询目标租户信息，确认PRIMARY_ZONE属性修改成功，第一优先级由zone1,zone2变更为zone1;zone2。

select primary_zone from oceanbase.dba_ob_tenants where tenant_id = 1004;+--------------+
| PRIMARY_ZONE |
+--------------+
|  zone1;zone2 |
+--------------+
1 row in set

再次查询目标租户日志流Leader副本位置的分布信息。

select tenant_id, ls_id, svr_ip, svr_port, zone, role, replica_type 
from oceanbase.cdb_ob_ls_locations where tenant_id = 1004 and ls_id != 1 and role = 'LEADER';+-----------+-------+---------------+----------+--------+--------+--------------+
| TENANT_ID | LS_ID | SVR_IP        | SVR_PORT | ZONE   | ROLE   | REPLICA_TYPE |
+-----------+-------+---------------+----------+--------+--------+--------------+
|      1004 |  1001 | 172.xx.xxx.xx |    2882  |  zone1 | LEADER | FULL         |
|      1004 |  1012 | 172.xx.xxx.xx |    2882  |  zone1 | LEADER | FULL         |
+-----------+-------+---------------+----------+--------+--------+--------------+
2 rows in set