Migrate units

This topic describes how to migrate units between OBServer nodes within a single zone. After you migrate units within a zone, the locations of the units change, but the number of units and the types of units in the zone remain unchanged. This feature is applicable to OBServer node failure scenarios and load balancing scenarios.

Procedure

The following example describes how to migrate the unit with the ID of 1006 in the mq_t1 tenant to another OBServer node in the same zone.

1. Log on to the sys tenant of the cluster as the root user.

   obclient -h172.30.xxx.xxx -P2883 -uroot@sys#obdemo -pxxxx -A
   

2. Access the database named oceanbase.

   obclient>use oceanbase;
   

3. Query tenant_id of the mq_t1 tenant.

   In this example, tenant_id of the mq_t1 tenant is 1004.

   obclient> SELECT * FROM oceanbase.DBA_OB_TENANTS WHERE TENANT_NAME = 'mq_t1';
   +-----------+-------------+-------------+----------------------------+----------------------------+----------------------------------------+------------------------------------------------------------------+-------------------+--------------------+--------+---------------+--------+-------------+-------------------+------------------+---------------------+---------------------+---------------------+---------------------+--------------+----------------------------+
   | TENANT_ID | TENANT_NAME | TENANT_TYPE | CREATE_TIME                | MODIFY_TIME                | PRIMARY_ZONE                           | LOCALITY                                                         | PREVIOUS_LOCALITY | COMPATIBILITY_MODE | STATUS | IN_RECYCLEBIN | LOCKED | TENANT_ROLE | SWITCHOVER_STATUS | SWITCHOVER_EPOCH | SYNC_SCN            | REPLAYABLE_SCN      | READABLE_SCN        | RECOVERY_UNTIL_SCN  | LOG_MODE     | ARBITRATION_SERVICE_STATUS |
   +-----------+-------------+-------------+----------------------------+----------------------------+----------------------------------------+------------------------------------------------------------------+-------------------+--------------------+--------+---------------+--------+-------------+-------------------+------------------+---------------------+---------------------+---------------------+---------------------+--------------+----------------------------+
   |      1004 | mq_t1       | USER        | 2023-01-04 11:57:11.384141 | 2023-01-04 11:57:37.866707 | sa128_obv4_1;sa128_obv4_2              | FULL{1}@sa128_obv4_1, FULL{1}@sa128_obv4_2                       | NULL              | MYSQL              | NORMAL | NO            | NO     | PRIMARY     | NORMAL            |                0 | 1684396167132057328 | 1684396167132057328 | 1684396167051160964 | 4611686018427387903 | NOARCHIVELOG | DISABLED                   |
   +-----------+-------------+-------------+----------------------------+----------------------------+----------------------------------------+------------------------------------------------------------------+-------------------+--------------------+--------+---------------+--------+-------------+-------------------+------------------+---------------------+---------------------+---------------------+---------------------+--------------+----------------------------+
   1 row in set
   

4. View the unit information of the mq_t1 tenant.

   In this example, the resource unit with the ID of 1006 is located on the node with the IP address of xx.xx.xx.19 in the sa128_obv4_3 zone.

   obclient> SELECT * FROM oceanbase.DBA_OB_UNITS WHERE TENANT_ID = 1004;
   +---------+-----------+--------+------------------+---------------+----------------------------+----------------------------+--------------+------------+----------+---------------------+-----------------------+----------------+----------------+---------+---------+-------------+---------------+----------+----------+-------------+
   | UNIT_ID | TENANT_ID | STATUS | RESOURCE_POOL_ID | UNIT_GROUP_ID | CREATE_TIME                | MODIFY_TIME                | ZONE         | SVR_IP     | SVR_PORT | MIGRATE_FROM_SVR_IP | MIGRATE_FROM_SVR_PORT | MANUAL_MIGRATE | UNIT_CONFIG_ID | MAX_CPU | MIN_CPU | MEMORY_SIZE | LOG_DISK_SIZE | MAX_IOPS | MIN_IOPS | IOPS_WEIGHT |
   +---------+-----------+--------+------------------+---------------+----------------------------+----------------------------+--------------+------------+----------+---------------------+-----------------------+----------------+----------------+---------+---------+-------------+---------------+----------+----------+-------------+
   |    1004 |      1004 | ACTIVE |             1005 |          1002 | 2023-01-04 11:48:36.582413 | 2023-01-04 11:57:11.387383 | sa128_obv4_1 | xx.xx.xx.47  |     2882 | NULL                |                  NULL | NULL           |           1006 |       3 |       3 | 12884901888 |   38654705664 |    30000 |    30000 |           3 |
   |    1005 |      1004 | ACTIVE |             1005 |          1002 | 2023-01-04 11:48:36.591414 | 2023-01-04 11:57:11.388449 | sa128_obv4_2 | xx.xx.xx.81 |     2882 | NULL                |                  NULL | NULL           |           1006 |       3 |       3 | 12884901888 |   38654705664 |    30000 |    30000 |           3 |
   |    1006 |      1004 | ACTIVE |             1005 |          1002 | 2023-01-04 14:13:36.980799 | 2023-01-04 14:13:36.980799 | sa128_obv4_3 | xx.xx.xx.19 |     2882 | NULL                |                  NULL | NULL           |           1006 |       3 |       3 | 12884901888 |   38654705664 |    30000 |    30000 |           3 |
   +---------+-----------+--------+------------------+---------------+----------------------------+----------------------------+--------------+------------+----------+---------------------+-----------------------+----------------+----------------+---------+---------+-------------+---------------+----------+----------+-------------+
   3 rows in set
   

5. View the IP addresses of OBServer nodes in the zone where the resource unit to be migrated resides.

   In this example, the sa128_obv4_3 zone contains two OBServer nodes with the IP addresses of xx.xx.xx.19 and xx.xx.xx.158.

   obclient> SELECT * FROM oceanbase.DBA_OB_SERVERS;
   +-------------+----------+----+--------------+----------+-----------------+--------+----------------------------+-----------+-----------------------+----------------------------+----------------------------+-------------------------------------------------------------------------------------------+
   | SVR_IP      | SVR_PORT | ID | ZONE         | SQL_PORT | WITH_ROOTSERVER | STATUS | START_SERVICE_TIME         | STOP_TIME | BLOCK_MIGRATE_IN_TIME | CREATE_TIME                | MODIFY_TIME                | BUILD_VERSION                                                                             |
   +-------------+----------+----+--------------+----------+-----------------+--------+----------------------------+-----------+-----------------------+----------------------------+----------------------------+-------------------------------------------------------------------------------------------+
   | xx.xx.xx.81  |     2882 |  6 | sa128_obv4_2 |     2881 | NO              | ACTIVE | 2022-12-30 16:17:03.173519 | NULL      | NULL                  | 2022-12-30 16:08:04.749100 | 2023-01-04 11:48:36.589270 | 4.0.0.0_101000022022120716-0d7927892ad6d830e28437af099f018b0ad9a322(Dec  7 2022 16:22:15) |
   | xx.xx.xx.19  |     2882 |  4 | sa128_obv4_3 |     2881 | NO              | ACTIVE | 2022-12-30 16:36:35.567437 | NULL      | NULL                  | 2022-12-30 16:08:02.755200 | 2023-01-04 14:13:36.976548 | 4.0.0.0_101000022022120716-0d7927892ad6d830e28437af099f018b0ad9a322(Dec  7 2022 16:22:15) |
   | xx.xx.xx.158 |     2882 |  3 | sa128_obv4_3 |     2881 | NO              | ACTIVE | 2022-12-12 12:42:00.054759 | NULL      | NULL                  | 2022-11-03 15:37:09.530894 | 2022-12-22 14:43:26.717736 | 4.0.0.0_101000022022120716-0d7927892ad6d830e28437af099f018b0ad9a322(Dec  7 2022 16:22:15) |
   | xx.xx.xx.43   |     2882 |  1 | sa128_obv4_1 |     2881 | NO              | ACTIVE | 2022-12-12 12:25:17.555651 | NULL      | NULL                  | 2022-11-03 15:37:08.990683 | 2022-12-12 12:25:18.553763 | 4.0.0.0_101000022022120716-0d7927892ad6d830e28437af099f018b0ad9a322(Dec  7 2022 16:22:15) |
   | xx.xx.xx.106  |     2882 |  2 | sa128_obv4_2 |     2881 | YES             | ACTIVE | 2022-12-12 11:46:37.222980 | NULL      | NULL                  | 2022-11-03 15:37:09.490511 | 2022-12-12 11:47:31.075335 | 4.0.0.0_101000022022120716-0d7927892ad6d830e28437af099f018b0ad9a322(Dec  7 2022 16:22:15) |
   | xx.xx.xx.47   |     2882 |  5 | sa128_obv4_1 |     2881 | NO              | ACTIVE | 2022-12-30 16:25:45.420996 | NULL      | NULL                  | 2022-12-30 16:08:03.928478 | 2023-01-04 11:48:36.578231 | 4.0.0.0_101000022022120716-0d7927892ad6d830e28437af099f018b0ad9a322(Dec  7 2022 16:22:15) |
   +-------------+----------+----+--------------+----------+-----------------+--------+----------------------------+-----------+-----------------------+----------------------------+----------------------------+-------------------------------------------------------------------------------------------+
   6 rows in set
   

6. Migrate the unit with the ID of 1006 in the mq_t1 tenant to another OBServer node in the same zone.

   obclient> ALTER SYSTEM migrate unit = 1006 destination = 'xx.xx.xx.158:2882';
   Query OK, 0 rows affected
   

7. View the status of the unit migration job.

   obclient> SELECT * FROM oceanbase.DBA_OB_UNIT_JOBS WHERE JOB_TYPE = 'MIGRATE_UNIT';
   +--------+--------------+------------+-------------+----------+----------------------------+----------------------------+-----------+---------+----------+------------+------------+-------------+
   | JOB_ID | JOB_TYPE     | JOB_STATUS | RESULT_CODE | PROGRESS | START_TIME                 | MODIFY_TIME                | TENANT_ID | UNIT_ID | SQL_TEXT | EXTRA_INFO | RS_SVR_IP  | RS_SVR_PORT |
   +--------+--------------+------------+-------------+----------+----------------------------+----------------------------+-----------+---------+----------+------------+------------+-------------+
   |      4 | MIGRATE_UNIT | INPROGRESS |        NULL |        0 | 2023-01-04 17:22:02.208219 | 2023-01-04 17:22:02.208219 |      1004 |    1006 | NULL     | NULL       | xx.xx.xx.106 |        2882 |
   +--------+--------------+------------+-------------+----------+----------------------------+----------------------------+-----------+---------+----------+------------+------------+-------------+
   1 row in set
   

   The value of JOB_STATUS in the query result indicates the job status. INPROGRESS indicates that the migration job is in progress, and SUCCESS indicates that the migration job is successful.

8. View the information of the migrated unit.

   obclient> SELECT * FROM oceanbase.DBA_OB_UNITS WHERE UNIT_ID = 1006;
   +---------+-----------+--------+------------------+---------------+----------------------------+----------------------------+--------------+-------------+----------+---------------------+-----------------------+----------------+----------------+---------+---------+-------------+---------------+----------+----------+-------------+
   | UNIT_ID | TENANT_ID | STATUS | RESOURCE_POOL_ID | UNIT_GROUP_ID | CREATE_TIME                | MODIFY_TIME                | ZONE         | SVR_IP      | SVR_PORT | MIGRATE_FROM_SVR_IP | MIGRATE_FROM_SVR_PORT | MANUAL_MIGRATE | UNIT_CONFIG_ID | MAX_CPU | MIN_CPU | MEMORY_SIZE | LOG_DISK_SIZE | MAX_IOPS | MIN_IOPS | IOPS_WEIGHT |
   +---------+-----------+--------+------------------+---------------+----------------------------+----------------------------+--------------+-------------+----------+---------------------+-----------------------+----------------+----------------+---------+---------+-------------+---------------+----------+----------+-------------+
   |    1006 |      1004 | ACTIVE |             1005 |          1002 | 2023-01-04 14:13:36.980799 | 2023-01-04 17:22:02.210245 | sa128_obv4_3 | xx.xx.xx.158 |     2882 | xx.xx.xx.19          |                  2882 | YES            |           1006 |       3 |       3 | 12884901888 |   38654705664 |    30000 |    30000 |           3 |
   +---------+-----------+--------+------------------+---------------+----------------------------+----------------------------+--------------+-------------+----------+---------------------+-----------------------+----------------+----------------+---------+---------+-------------+---------------+----------+----------+-------------+
   3 rows in set
   

The query result shows that the unit with the ID of 1006 is migrated from xx.xx.xx.19 to xx.xx.xx.158.