Flashback a Pluggable Database in 12c R2

In Oracle Database 12.1 flashback database operations were limited to the root container, and therefore affected all pluggable databases (PDBs) associated with the root container. Oracle Database 12.2 now supports flashback of a pluggable database.

My environment details- 

Primary - SRORCL
Standby - TRORCL

At primary-

C:\Users\Mahesh>set ORACLE_SID=SRORCL
C:\Users\Mahesh>sqlplus / as sysdba
SQL*Plus: Release 12.2.0.1.0 Production on Sat Jun 6 12:02:16 2020
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production

SQL> select * from database_properties where property_name='LOCAL_UNDO_ENABLED';

PROPERTY_NAME
--------------------------------------------------------------------------------
PROPERTY_VALUE
--------------------------------------------------------------------------------
DESCRIPTION
--------------------------------------------------------------------------------
LOCAL_UNDO_ENABLED
TRUE
true if local undo is enabled

SQL> select name ,db_unique_name,open_mode,database_role from v$database;

NAME       DB_UNIQUE_NA OPEN_MODE            DATABASE_ROLE
---------- ------------ -------------------- ----------------
SRORCL     SRORCL       READ WRITE           PRIMARY

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          READ WRITE NO
         4 SRPDB_DUP                      READ WRITE NO
SQL> select flashback_on from v$database ;

FLASHBACK_ON
------------------
YES

SQL>

At standby-

SQL> select name ,db_unique_name,open_mode,database_role from v$database;

NAME       DB_UNIQUE_NA OPEN_MODE            DATABASE_ROLE
---------- ------------ -------------------- ----------------
SRORCL     TRORCL       READ ONLY WITH APPLY PHYSICAL STANDBY

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          READ ONLY  NO
         4 SRPDB_DUP                      READ ONLY  NO

SQL> SELECT PROCESS, STATUS, THREAD#, SEQUENCE#, BLOCK#, BLOCKS FROM V$MANAGED_STANDBY;

PROCESS   STATUS          THREAD#  SEQUENCE#     BLOCK#     BLOCKS
--------- ------------ ---------- ---------- ---------- ----------
DGRD      ALLOCATED             0          0          0          0
ARCH      CONNECTED             0          0          0          0
DGRD      ALLOCATED             0          0          0          0
ARCH      CLOSING               1        107          1        380
ARCH      CLOSING               1        105      51200         32
ARCH      CLOSING               1        106      20480       1341
RFS       IDLE                  0          0          0          0
RFS       IDLE                  1        108      23870          1
RFS       IDLE                  0          0          0          0
RFS       IDLE                  0          0          0          0
MRP0      APPLYING_LOG          1        108      23870     409600

11 rows selected.

SQL> select flashback_on from v$database ;

FLASHBACK_ON
------------------
YES

SQL>

At Primary database truncate one table-

SQL> alter session set container=SRPDB;

Session altered.

SQL> select systimestamp from dual;

SYSTIMESTAMP
---------------------------------------------------------------------------
06-JUN-20 11.55.39.355000 AM +05:30

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         3 SRPDB                          READ WRITE NO
SQL>
SQL> select count(1) from hr.job_history;

  COUNT(1)
----------
        10

SQL> truncate table hr.job_history;

Table truncated.

SQL>

SQL> select count(1) from hr.job_history;

  COUNT(1)
----------
         0

SQL>

Now flashback the primary database to get the table content back.

SQL> alter session set container=SRPDB;

Session altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         3 SRPDB                          READ WRITE NO
SQL> shut immediate ;
Pluggable Database closed.
SQL>
SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         3 SRPDB                          MOUNTED
SQL>
SQL> exit
Disconnected from Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production

C:\Users\Mahesh>set ORACLE_SID=SRORCL
C:\Users\Mahesh>sqlplus / as sysdba
SQL*Plus: Release 12.2.0.1.0 Production on Sat Jun 6 12:05:36 2020
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production

SQL> FLASHBACK PLUGGABLE DATABASE SRPDB TO TIMESTAMP TO_TIMESTAMP('2020-06-06 11:55:39', 'YYYY-MM-DD HH24:MI:SS');

Flashback complete.

SQL>

Below is the alert log entry-

Flashback Restore Start
2020-06-06 12:13:57.668000 +05:30
Restore Flashback Pluggable Database SRPDB (3) until change 4401023
Flashback Restore Complete
Flashback Media Recovery Start
Serial Media Recovery started
2020-06-06 12:13:59.012000 +05:30
Recovery of Online Redo Log: Thread 1 Group 2 Seq 106 Reading mem 0
  Mem# 0: F:\ORADATA\SRORCL\ONLINELOG\O1_MF_2_H5544RWG_.LOG
  Mem# 1: F:\ORADATA\ORAFRA\SRORCL\ONLINELOG\O1_MF_2_H5545FBT_.LOG
2020-06-06 12:14:05.213000 +05:30
Recovery of Online Redo Log: Thread 1 Group 3 Seq 107 Reading mem 0
  Mem# 0: F:\ORADATA\SRORCL\ONLINELOG\O1_MF_3_H5544RXG_.LOG
  Mem# 1: F:\ORADATA\ORAFRA\SRORCL\ONLINELOG\O1_MF_3_H5545FQ0_.LOG
Recovery of Online Redo Log: Thread 1 Group 1 Seq 108 Reading mem 0
  Mem# 0: F:\ORADATA\SRORCL\ONLINELOG\O1_MF_1_H5544RTJ_.LOG
  Mem# 1: F:\ORADATA\ORAFRA\SRORCL\ONLINELOG\O1_MF_1_H5545F40_.LOG
2020-06-06 12:14:06.551000 +05:30
Incomplete Recovery applied until change 4404404 time 06/06/2020 11:55:40
Flashback Media Recovery Complete
Flashback Pluggable Database SRPDB (3) recovered until change 4404404, at 06/06/2020 11:55:40
Completed: FLASHBACK PLUGGABLE DATABASE SRPDB TO TIMESTAMP TO_TIMESTAMP('2020-06-06 11:55:39', 'YYYY-MM-DD HH24:MI:SS')

SQL> alter pluggable database SRPDB open resetlogs;

Pluggable database altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          READ WRITE NO
         4 SRPDB_DUP                      READ WRITE NO

SQL> alter session set container=SRPDB;

Session altered.

SQL> select count(1) from hr.job_history;

  COUNT(1)
----------
        10

SQL>

We recovered our table back, but if you check the standby alert logfile, could see MRP has been crashed. Below is the alertlog entry from standby database.

Recovery of pluggable database SRPDB aborted due to pluggable database open resetlog marker.
To continue recovery, restore all data files for this PDB to checkpoint SCN lower than 4404404, or timestamp before 06/06/2020 11:55:40, and restart recovery
MRP0: Background Media Recovery terminated with error 39874
Errors in file F:\APP\MAHESH\diag\rdbms\trorcl\trorcl\trace\trorcl_pr00_4336.trc:
ORA-39874: Pluggable Database SRPDB recovery halted
ORA-39873: Restore all data files to a checkpoint SCN lower than 4404404.
Managed Standby Recovery not using Real Time Apply
Recovery interrupted!
2020-06-06 12:15:43.266000 +05:30
Recovered data files to a consistent state at change 4407458
Errors in file F:\APP\MAHESH\diag\rdbms\trorcl\trorcl\trace\trorcl_pr00_4336.trc:
ORA-39874: Pluggable Database SRPDB recovery halted
ORA-39873: Restore all data files to a checkpoint SCN lower than 4404404.

C:\Users\Mahesh>set ORACLE_SID=TRORCL
C:\Users\Mahesh>sqlplus / as sysdba
SQL*Plus: Release 12.2.0.1.0 Production on Sat Jun 6 12:18:41 2020
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production

SQL> SELECT PROCESS, STATUS, THREAD#, SEQUENCE#, BLOCK#, BLOCKS FROM V$MANAGED_STANDBY;

PROCESS   STATUS          THREAD#  SEQUENCE#     BLOCK#     BLOCKS
--------- ------------ ---------- ---------- ---------- ----------
DGRD      ALLOCATED             0          0          0          0
ARCH      CONNECTED             0          0          0          0
DGRD      ALLOCATED             0          0          0          0
ARCH      CLOSING               1        107          1        380
ARCH      CLOSING               1        105      51200         32
ARCH      CLOSING               1        106      20480       1341
RFS       IDLE                  0          0          0          0
RFS       IDLE                  1        108      26760          1
RFS       IDLE                  0          0          0          0
RFS       IDLE                  0          0          0          0

10 rows selected.

SQL>

Check the current PDB incarnation from  v$pdb_incarnation and we can confirm that same SCN has been recorded in standby alert logfile as well.

SQL> alter session set container=SRPDB;

Session altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         3 SRPDB                          READ WRITE NO
SQL> select status,INCARNATION_SCN from v$pdb_incarnation;

STATUS  INCARNATION_SCN
------- ---------------
CURRENT         4404404
PARENT          1490582

SQL>

Let flashback the standby PDB to a SCN lower than 4404404, let say to SCN 4404402.

C:\Users\Mahesh>set ORACLE_SID=TRORCL
C:\Users\Mahesh>sqlplus / as sysdba
SQL*Plus: Release 12.2.0.1.0 Production on Sat Jun 6 12:26:53 2020
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          READ ONLY  NO
         4 SRPDB_DUP                      READ ONLY  NO
SQL> alter pluggable database SRPDB close immediate ;

Pluggable database altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          MOUNTED
         4 SRPDB_DUP                      READ ONLY  NO
SQL>

Let's try to do the flashback now.

SQL> flashback pluggable database SRPDB to scn 4404402;
flashback pluggable database SRPDB to scn 4404402
*
ERROR at line 1:
ORA-01126: database must be mounted in this instance and not open in any instance

SQL>

So it looks like it's not possible to flashback a PDB just by mounting only the affected PDB. We need to start the standby CDB in mount mode.

SQL> shut immediate ;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup mount;
ORACLE instance started.
Total System Global Area  734003200 bytes
Fixed Size                  8923240 bytes
Variable Size             348129176 bytes
Database Buffers          369098752 bytes
Redo Buffers                7852032 bytes
Database mounted.
SQL>
SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       MOUNTED
         3 SRPDB                          MOUNTED
         4 SRPDB_DUP                      MOUNTED
SQL> flashback pluggable database SRPDB to scn 4404402;

Flashback complete.

SQL>

Alertlog entry-

flashback pluggable database SRPDB to scn 4404402
2020-06-06 12:36:53.275000 +05:30
Flashback Restore Start
Restore Flashback Pluggable Database SRPDB (3) until change 4400347
2020-06-06 12:36:54.305000 +05:30
Flashback Restore Complete
Completed: flashback pluggable database SRPDB to scn 4404402

Lets enable MRP now 

SQL> SELECT PROCESS, STATUS, THREAD#, SEQUENCE#, BLOCK#, BLOCKS FROM V$MANAGED_STANDBY;

PROCESS   STATUS          THREAD#  SEQUENCE#     BLOCK#     BLOCKS
--------- ------------ ---------- ---------- ---------- ----------
DGRD      ALLOCATED             0          0          0          0
ARCH      CONNECTED             0          0          0          0
DGRD      ALLOCATED             0          0          0          0
ARCH      CONNECTED             0          0          0          0
ARCH      CLOSING               1        108      36864       1656
ARCH      CONNECTED             0          0          0          0
RFS       IDLE                  0          0          0          0
RFS       IDLE                  1        109        360          1

8 rows selected.

SQL> recover managed standby database disconnect from session;
Media recovery complete.

SQL> SELECT PROCESS, STATUS, THREAD#, SEQUENCE#, BLOCK#, BLOCKS FROM V$MANAGED_STANDBY;

PROCESS   STATUS          THREAD#  SEQUENCE#     BLOCK#     BLOCKS
--------- ------------ ---------- ---------- ---------- ----------
DGRD      ALLOCATED             0          0          0          0
ARCH      CONNECTED             0          0          0          0
DGRD      ALLOCATED             0          0          0          0
ARCH      CONNECTED             0          0          0          0
ARCH      CLOSING               1        108      36864       1656
ARCH      CONNECTED             0          0          0          0
RFS       IDLE                  0          0          0          0
RFS       RECEIVING             1        109        380          1
MRP0      APPLYING_LOG          1        108      38518      38519

9 rows selected.

SQL>

I did some log switch on the primary and verified standby got catch up.

SQL> SELECT ARCH.THREAD# “Thread”, ARCH.SEQUENCE# “Last Sequence Received”, APPL.SEQUENCE# “Last Sequence Applied”,
  2      (ARCH.SEQUENCE# – APPL.SEQUENCE#) “Difference” FROM (SELECT THREAD# ,SEQUENCE# FROM V$ARCHIVED_LOG
  3     WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME) FROM V$ARCHIVED_LOG GROUP BY THREAD#)) ARCH,
  4     (SELECT THREAD# ,SEQUENCE# FROM V$LOG_HISTORY WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME)
  5     FROM V$LOG_HISTORY GROUP BY THREAD#)) APPL WHERE ARCH.THREAD# = APPL.THREAD# ORDER BY 1;

    Thread Last Sequence Received Last Sequence Applied Difference
---------- ---------------------- --------------------- ----------
         1                    110                   110          0

SQL>

Let's Open the PDB in read only and verify the table content 

SQL> recover managed standby database cancel;
Media recovery complete.
SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       MOUNTED
         3 SRPDB                          MOUNTED
         4 SRPDB_DUP                      MOUNTED
SQL> alter database open ;

Database altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          MOUNTED
         4 SRPDB_DUP                      MOUNTED
SQL> alter pluggable database all open;

Pluggable database altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          READ ONLY  NO
         4 SRPDB_DUP                      READ ONLY  NO

SQL> recover managed standby database disconnect from session;
Media recovery complete.

SQL> SELECT PROCESS, STATUS, THREAD#, SEQUENCE#, BLOCK#, BLOCKS FROM V$MANAGED_STANDBY;

PROCESS   STATUS          THREAD#  SEQUENCE#     BLOCK#     BLOCKS
--------- ------------ ---------- ---------- ---------- ----------
DGRD      ALLOCATED             0          0          0          0
ARCH      CONNECTED             0          0          0          0
DGRD      ALLOCATED             0          0          0          0
ARCH      CLOSING               1        110          1         18
ARCH      CLOSING               1        108      36864       1656
ARCH      CLOSING               1        109          1        430
RFS       IDLE                  0          0          0          0
RFS       IDLE                  1        111        403          1
MRP0      APPLYING_LOG          1        111        403     409600

9 rows selected.

SQL> alter session set container=SRPDB;

Session altered.

SQL> select count(1) from hr.job_history;

  COUNT(1)
----------
        10

SQL>

Flashback and restore point in Container architecture - A study note

Flashback at container database-

In Oracle Database 12.1 flashback database operations were limited to the root container, and therefore affected all pluggable databases(PDBs) associated with the root container. Oracle Database 12.2 now supports flashback of a pluggable database.

In Oracle Database 12c Release 1 all containers in an instance shared the same undo tablespace. This mode is called SHARED UNDO MODE. In Oracle 12c Release 2 each container in an instance can use its own undo tablespace this is called LOCAL UNDO MODE. This mode is the default mode in this release.

select * from database_properties where property_name='LOCAL_UNDO_ENABLED';

Irrespective of local undo enabled or not, you can flashback a PDB in 12cR2.

In oracle 12.2 if local_undo is not enabled, then we can use AUXILIARY DESTINATION parameter , which will create an auxiliary instance with container database’s system,sysaux and undo tablespace, and then restore the PDB using rollback transactions. However this flahback will take a long time and will consume additional space on the auxiliary destination.

SQL> alter pluggable database SRPDB close;

SQL> flashback pluggable database SRPDB to SCN 345678 auxiliary destination '/oradata/aux_inst';

SQL> alter pluggable database SRPDBopen resetlogs;

Some facts about restore point in container database-

CDB restore points are accessible to every pluggable database (PDB) within the CDB. However, a CDB restore point does not reflect the PDB sub-incarnation of any of its PDBs.

CDB restore points are useful in the following scenarios:

The whole CDB needs to be recovered to a particular point in time.

Multiple PDBs in a CDB need to be recovered to a particular point in time.

PDB restore points are accessible only to the PDB in which they are defined. Creating a guaranteed PDB restore point requires careful consideration because such a restore point can prevent required flashback logs in the multitenant container database (CDB) from being reused. This can potentially impact CDB functioning because the fast recovery area could run out of space.

Clean PDB Restore Points

A clean PDB restore point is a PDB restore point that is created when the PDB is closed and when there are no outstanding transactions for that PDB. Clean PDB restore points are only applicable to CDBs that use shared undo.

Clean PDB restore points can be normal or guaranteed restore points. Use the CREATE CLEAN RESTORE POINT command to explicitly create a clean PDB restore point. For a CDB that uses shared undo, if a PDB is closed and it has no outstanding transactions, any PDB restore point created is marked as a clean PDB restore point.

If you anticipate that you may need to rewind a PDB to a particular point in time, for example, to a state just before an application upgrade, then it is recommended that you create a clean PDB guaranteed restore point.

For CDBs that use shared undo, a Flashback Database operation to a clean PDB restore point is faster than a Flashback Database operation to an SCN or other restore points that are not clean PDB restore points. This is because RMAN does not need to restore any backups while performing a flashback operation to a clean PDB restore point.

PDB restore points are accessible only to the PDB in which they are defined.

Cloning PDB using standbys=none in Dataguard Environment

Prior to release 12.1.0.2, when adding a pluggable database in the primary of a Data Guard configuration, all files associated with the new PDB needed to be in place, accessible, in the correct state (the same state as the unplug left them) and in the expected location on the physical standby for redo apply to continue operations normally.  If any of the requirements were missed, redo apply would stop and would not be allowed to continue until the issues were resolved and the files successfully added to the database controlfile. But when you do remote clone of a PDB, It is not possible to pre-copy the files to the physical standby database and ensure they will be in the correct state when the CREATE PLUGGABLE DATABASE statement redo is applied to the standby.

In 12.1.0.2, the CREATE PLUGGABLE DATABASE statement has a new clause, STANDBYS=NONE, that allows for deferral of file instantiation on the standby allowing the physical standby database to continue to protect existing pluggable databases. The clause allows the general structure of the PDB to be created on all physical standbys but all files belonging to the PDB are marked as OFFLINE/RECOVER at the standby.  The affected PDB cannot be opened with the files in this state, although any other PDBs not in this state can be opened Read/Only with Active Data Guard as usual.  You can check the recovery status of PDBs by querying V$PDBS and looking at the value of RECOVERY_STATUS which will show either DISABLED or ENABLED.  You can check the status of the datafiles in V$RECOVER_FILE.ONLINE where CON_ID is equal to the container id of your PDB.

The problem is, that Oracle has to manage two different redo streams: the redo, that is generated during the hot clone of the PDB, and the normal redo transport to the standby database.

18c new feature - 

New pluggable databases (PDBs) created from the seed, or as a clone of an existing read-only PDB in the local root container are handled automatically by Data Guard. New PDBs created by a remote clone or a plugin operation are not managed automatically. The STANDBY_PDB_SOURCE_FILE_DBLINK and STANDBY_PDB_SOURCE_FILE_DIRECTORY initialisation parameters make remote clones and plugin operations much simpler in Oracle 18c.This feature is available from 12.1.0.2 when patched appropriately, as described in MOS Doc ID 2274735.1, but 18c is the first time it has been documented in the official documentation.

In this Post we will take a look at the usage of standbys=none in a multi-tenant environment.

My environment details-

SRORCL is Primary CDB database.

TRORCL is Standby CDB database.

At Primary- 

SQL> select name ,db_unique_name,open_mode,database_role from v$database;

NAME       DB_UNIQUE_NA OPEN_MODE            DATABASE_ROLE
---------- ------------ -------------------- ----------------
SRORCL     SRORCL       READ WRITE           PRIMARY

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          READ WRITE NO
SQL>

At standby-

SQL> select name ,db_unique_name,open_mode,database_role from v$database;

NAME       DB_UNIQUE_NA OPEN_MODE            DATABASE_ROLE
---------- ------------ -------------------- ----------------
SRORCL     TRORCL       READ ONLY WITH APPLY PHYSICAL STANDBY

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          READ ONLY  NO

SQL> SELECT PROCESS, STATUS, THREAD#, SEQUENCE#, BLOCK#, BLOCKS FROM V$MANAGED_STANDBY;

PROCESS   STATUS          THREAD#  SEQUENCE#     BLOCK#     BLOCKS
--------- ------------ ---------- ---------- ---------- ----------
DGRD      ALLOCATED             0          0          0          0
ARCH      CLOSING               1         95       2048        150
DGRD      ALLOCATED             0          0          0          0
ARCH      CONNECTED             0          0          0          0
ARCH      CONNECTED             0          0          0          0
ARCH      CLOSING               1         96       2048       1770
RFS       IDLE                  0          0          0          0
RFS       IDLE                  1         97       1278          1
RFS       IDLE                  0          0          0          0
MRP0      APPLYING_LOG          1         97       1278     409600

10 rows selected.

Let's clone a new PDB using standbys=none option.

Please note, we are keeping our source PDB in read write mode.

SQL> create pluggable database SRPDB_DUP from SRPDB standbys=none;

Pluggable database created.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          READ ONLY  NO
         4 SRPDB_DUP                      MOUNTED
SQL> alter pluggable database SRPDB_DUP open;

Pluggable database altered.

SQL> alter pluggable database SRPDB close immediate ;

Pluggable database altered.

SQL>  alter pluggable database SRPDB open;

Pluggable database altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          READ WRITE NO
         4 SRPDB_DUP                      READ WRITE NO
SQL>

Below is the entry made on standby alertlog file-

Recovery created pluggable database SRPDB_DUP
File #28 added to control file as 'UNNAMED00028'. Originally created as:
'F:\ORADATA\SRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_SYSTEM_HF6NRRPQ_.DBF'
because the pluggable database was created with nostandby
or the tablespace belonging to the pluggable database is
offline.
2020-05-31 12:18:47.530000 +05:30
File #29 added to control file as 'UNNAMED00029'. Originally created as:
'F:\ORADATA\SRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_SYSAUX_HF6NRRY4_.DBF'
because the pluggable database was created with nostandby
or the tablespace belonging to the pluggable database is
offline.
2020-05-31 12:18:49.388000 +05:30
File #30 added to control file as 'UNNAMED00030'. Originally created as:
'F:\ORADATA\SRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_UNDOTBS1_HF6NRS01_.DBF'
because the pluggable database was created with nostandby
or the tablespace belonging to the pluggable database is
offline.
2020-05-31 12:18:51.597000 +05:30
File #31 added to control file as 'UNNAMED00031'. Originally created as:
'F:\ORADATA\SRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_USERS_HF6NRS2R_.DBF'
because the pluggable database was created with nostandby
or the tablespace belonging to the pluggable database is
offline.

Check the standby-

SQL> select name ,db_unique_name,open_mode,database_role from v$database;

NAME       DB_UNIQUE_NA OPEN_MODE            DATABASE_ROLE
---------- ------------ -------------------- ----------------
SRORCL     TRORCL       READ ONLY WITH APPLY PHYSICAL STANDBY

SQL> SELECT ARCH.THREAD# “Thread”, ARCH.SEQUENCE# “Last Sequence Received”, APPL.SEQUENCE# “Last Sequence Applied”,
  2   (ARCH.SEQUENCE# – APPL.SEQUENCE#) “Difference” FROM (SELECT THREAD# ,SEQUENCE# FROM V$ARCHIVED_LOG
  3  WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME) FROM V$ARCHIVED_LOG GROUP BY THREAD#)) ARCH,
  4  (SELECT THREAD# ,SEQUENCE# FROM V$LOG_HISTORY WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME)
  5  FROM V$LOG_HISTORY GROUP BY THREAD#)) APPL WHERE ARCH.THREAD# = APPL.THREAD# ORDER BY 1;

    Thread Last Sequence Received Last Sequence Applied Difference
---------- ---------------------- --------------------- ----------
         1                     96                    96          0

SQL>

Do some log switch and verify standby is catching up with the primary.

SQL> select name ,db_unique_name,open_mode,database_role from v$database;

NAME       DB_UNIQUE_NA OPEN_MODE            DATABASE_ROLE
---------- ------------ -------------------- ----------------
SRORCL     SRORCL       READ WRITE           PRIMARY

SQL> alter system switch logfile;

System altered.

SQL> alter system switch logfile;

System altered.

SQL>

Now at standby check the sync status-

SQL> select name ,db_unique_name,open_mode,database_role from v$database;

NAME       DB_UNIQUE_NA OPEN_MODE            DATABASE_ROLE
---------- ------------ -------------------- ----------------
SRORCL     TRORCL       READ ONLY WITH APPLY PHYSICAL STANDBY

SQL> SELECT ARCH.THREAD# “Thread”, ARCH.SEQUENCE# “Last Sequence Received”, APPL.SEQUENCE# “Last Sequence Applied”,
  2   (ARCH.SEQUENCE# – APPL.SEQUENCE#) “Difference” FROM (SELECT THREAD# ,SEQUENCE# FROM V$ARCHIVED_LOG
  3  WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME) FROM V$ARCHIVED_LOG GROUP BY THREAD#)) ARCH,
  4  (SELECT THREAD# ,SEQUENCE# FROM V$LOG_HISTORY WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME)
  5  FROM V$LOG_HISTORY GROUP BY THREAD#)) APPL WHERE ARCH.THREAD# = APPL.THREAD# ORDER BY 1;

    Thread Last Sequence Received Last Sequence Applied Difference
---------- ---------------------- --------------------- ----------
         1                     98                    98          0

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          READ ONLY  NO
         4 SRPDB_DUP                      MOUNTED
SQL>

Standby is in sync, it's not affected by the PDB creation on the primary.

SQL> select name, recovery_status from v$pdbs;

NAME                   RECOVERY
---------------------- --------
PDB$SEED               ENABLED
SRPDB                  ENABLED
SRPDB_DUP              DISABLED

SQL> alter session set container=SRPDB_DUP;

Session altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         4 SRPDB_DUP                      MOUNTED
SQL> select name, status from v$datafile;

NAME                                                                                     STATUS
---------------------------------------------------------------------------------------- -------
F:\APP\MAHESH\PRODUCT\12.2.0\DBHOME_1\DATABASE\UNNAMED00028                              SYSOFF
F:\APP\MAHESH\PRODUCT\12.2.0\DBHOME_1\DATABASE\UNNAMED00029                              RECOVER
F:\APP\MAHESH\PRODUCT\12.2.0\DBHOME_1\DATABASE\UNNAMED00030                              RECOVER
F:\APP\MAHESH\PRODUCT\12.2.0\DBHOME_1\DATABASE\UNNAMED00031                              RECOVER
SQL> select * from v$recover_file;

     FILE# ONLINE  ONLINE_ ERROR                   CHANGE# TIME          CON_ID
---------- ------- ------- -------------------- ---------- --------- ----------
        28 OFFLINE OFFLINE FILE MISSING                  0                    4
        29 OFFLINE OFFLINE FILE MISSING                  0                    4
        30 OFFLINE OFFLINE FILE MISSING                  0                    4
        31 OFFLINE OFFLINE FILE MISSING                  0                    4
SQL>

As per MOS note 1916648.1 , at this stage we can even perform a switch over operation.

To get the datafiles of the newly created PDB at standby side we can make use of RMAN.

To prepare for the RMAN copy of the files, create a small run block like the following while connected to the standby database using RMAN.  This method is preferred as RMAN will rename all of the 
datafiles in the standby controlfile to match those created during the restore process.  If RMAN was not used, you would have to manually rename each datafile prior to being able to ENABLE RECOVERY on the PDB.In the  following code, specify the PDB name that does not have recovery enabled.  The FROM SERVICE clause should identify a TNS alias that will connect to the primary database. 

run
{
set newname for pluggable database SRPDB_DUP to new;
 restore pluggable database SRPDB_DUP from service SRORCL;
switch datafile all;
 }

Execute the command block create above to restore the files from the primary to the standby.  Connect only to your standby database as target and run the block.

C:\Users\Mahesh>set ORACLE_SID=TRORCL

C:\Users\Mahesh>rman target /
Recovery Manager: Release 12.2.0.1.0 - Production on Sun May 31 12:51:35 2020
Copyright (c) 1982, 2017, Oracle and/or its affiliates.  All rights reserved.
connected to target database: SRORCL (DBID=3570490003)
RMAN> run
2> {
3> set newname for pluggable database SRPDB_DUP to new;
4>  restore pluggable database SRPDB_DUP from service SRORCL;
5> switch datafile all;
6>  }
executing command: SET NEWNAME
Starting restore at 31-MAY-20
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=394 device type=DISK
allocated channel: ORA_DISK_2
channel ORA_DISK_2: SID=133 device type=DISK
allocated channel: ORA_DISK_3
channel ORA_DISK_3: SID=269 device type=DISK
allocated channel: ORA_DISK_4
channel ORA_DISK_4: SID=396 device type=DISK
channel ORA_DISK_1: starting datafile backup set restore
channel ORA_DISK_1: using network backup set from service SRORCL
channel ORA_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_DISK_1: restoring datafile 00028 to F:\ORADATA\TRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_SYSTEM_%U_.DBF
channel ORA_DISK_2: starting datafile backup set restore
channel ORA_DISK_2: using network backup set from service SRORCL
channel ORA_DISK_2: specifying datafile(s) to restore from backup set
channel ORA_DISK_2: restoring datafile 00029 to F:\ORADATA\TRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_SYSAUX_%U_.DBF
channel ORA_DISK_3: starting datafile backup set restore
channel ORA_DISK_3: using network backup set from service SRORCL
channel ORA_DISK_3: specifying datafile(s) to restore from backup set
channel ORA_DISK_3: restoring datafile 00030 to F:\ORADATA\TRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_UNDOTBS1_%U_.DBF
channel ORA_DISK_4: starting datafile backup set restore
channel ORA_DISK_4: using network backup set from service SRORCL
channel ORA_DISK_4: specifying datafile(s) to restore from backup set
channel ORA_DISK_4: restoring datafile 00031 to F:\ORADATA\TRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_USERS_%U_.DBF
channel ORA_DISK_3: restore complete, elapsed time: 00:00:41
channel ORA_DISK_4: restore complete, elapsed time: 00:00:39
channel ORA_DISK_1: restore complete, elapsed time: 00:00:56
channel ORA_DISK_2: restore complete, elapsed time: 00:00:54
Finished restore at 31-MAY-20
datafile 28 switched to datafile copy
input datafile copy RECID=25 STAMP=1041857552 file name=F:\ORADATA\TRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_SYSTEM_HF6PRF7X_.DBF
datafile 29 switched to datafile copy
input datafile copy RECID=26 STAMP=1041857559 file name=F:\ORADATA\TRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_SYSAUX_HF6PRJ40_.DBF
datafile 30 switched to datafile copy
input datafile copy RECID=24 STAMP=1041857547 file name=F:\ORADATA\TRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_UNDOTBS1_HF6PRWCH_.DBF
datafile 31 switched to datafile copy
input datafile copy RECID=23 STAMP=1041857546 file name=F:\ORADATA\TRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_USERS_HF6PS8VQ_.DBF
RMAN>

C:\Users\Mahesh>set ORACLE_SID=TRORCL
C:\Users\Mahesh>sqlplus / as sysdba
SQL*Plus: Release 12.2.0.1.0 Production on Sun May 31 12:59:33 2020
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production

SQL>  select * from v$recover_file;

no rows selected

SQL>  select name, recovery_status from v$pdbs;

NAME              RECOVERY
----------------- --------
PDB$SEED          ENABLED
SRPDB             ENABLED
SRPDB_DUP         DISABLED

SQL> alter session set container=SRPDB_DUP;

Session altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         4 SRPDB_DUP                      MOUNTED
SQL> select name, status from v$datafile;

NAME                                                                                       STATUS
------------------------------------------------------------------------------------------ -------
F:\ORADATA\TRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_SYSTEM_HF6PRF7X_.DBF     SYSTEM
F:\ORADATA\TRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_SYSAUX_HF6PRJ40_.DBF     RECOVER
F:\ORADATA\TRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_UNDOTBS1_HF6PRWCH_.DBF   RECOVER
F:\ORADATA\TRORCL\E664B939B2D54120B226E71BF79BF257\DATAFILE\O1_MF_USERS_HF6PS8VQ_.DBF      RECOVER

SQL> alter pluggable database enable recovery;
alter pluggable database enable recovery
*
ERROR at line 1:
ORA-01156: recovery or flashback in progress may need access to files

SQL> SELECT PROCESS, STATUS, THREAD#, SEQUENCE#, BLOCK#, BLOCKS FROM V$MANAGED_STANDBY;

PROCESS   STATUS          THREAD#  SEQUENCE#     BLOCK#     BLOCKS
--------- ------------ ---------- ---------- ---------- ----------
DGRD      ALLOCATED             0          0          0          0
ARCH      CLOSING               1         95       2048        150
DGRD      ALLOCATED             0          0          0          0
ARCH      CLOSING               1         98          1          6
ARCH      CONNECTED             0          0          0          0
ARCH      CLOSING               1         97       8192       1122
RFS       IDLE                  0          0          0          0
RFS       IDLE                  1         99      14147          1
RFS       IDLE                  0          0          0          0
MRP0      APPLYING_LOG          1         99      14147     409600

10 rows selected.

SQL> recover managed standby database cancel;
ORA-65040: operation not allowed from within a pluggable database
SQL> exit
Disconnected from Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production

C:\Users\Mahesh>set ORACLE_SID=TRORCL
C:\Users\Mahesh>sqlplus / as sysdba
SQL*Plus: Release 12.2.0.1.0 Production on Sun May 31 13:03:02 2020
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
SQL> recover managed standby database cancel;
Media recovery complete.
SQL>
SQL>  alter session set container=SRPDB_DUP;

Session altered.

SQL>  alter pluggable database enable recovery;

Pluggable database altered.

SQL>  select name, recovery_status from v$pdbs;

NAME            RECOVERY
--------------- --------
SRPDB_DUP       ENABLED

SQL>

Now enable recovery at CDB level-

SQL>  alter session set container=CDB$ROOT;

Session altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 SRPDB                          READ ONLY  NO
         4 SRPDB_DUP                      MOUNTED
SQL> alter database recover managed standby database disconnect from session;

Database altered.

SQL> SELECT PROCESS, STATUS, THREAD#, SEQUENCE#, BLOCK#, BLOCKS FROM V$MANAGED_STANDBY;

PROCESS   STATUS          THREAD#  SEQUENCE#     BLOCK#     BLOCKS
--------- ------------ ---------- ---------- ---------- ----------
DGRD      ALLOCATED             0          0          0          0
ARCH      CLOSING               1         95       2048        150
DGRD      ALLOCATED             0          0          0          0
ARCH      CLOSING               1         98          1          6
ARCH      CONNECTED             0          0          0          0
ARCH      CLOSING               1         97       8192       1122
RFS       IDLE                  0          0          0          0
RFS       IDLE                  1         99      17048          1
RFS       IDLE                  0          0          0          0
MRP0      APPLYING_LOG          1         99      14334     409600

10 rows selected.
SQL> recover managed standby database cancel;
Media recovery complete.
SQL> alter pluggable database SRPDB_DUP open;

Pluggable database altered.

SQL>

SQL>  SELECT ARCH.THREAD# “Thread”, ARCH.SEQUENCE# “Last Sequence Received”, APPL.SEQUENCE# “Last Sequence Applied”,
  2       (ARCH.SEQUENCE# – APPL.SEQUENCE#) “Difference” FROM (SELECT THREAD# ,SEQUENCE# FROM V$ARCHIVED_LOG
  3      WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME) FROM V$ARCHIVED_LOG GROUP BY THREAD#)) ARCH,
  4      (SELECT THREAD# ,SEQUENCE# FROM V$LOG_HISTORY WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME)
  5      FROM V$LOG_HISTORY GROUP BY THREAD#)) APPL WHERE ARCH.THREAD# = APPL.THREAD# ORDER BY 1;

    Thread Last Sequence Received Last Sequence Applied Difference
---------- ---------------------- --------------------- ----------
         1                    104                    98          6

SQL> recover managed standby database disconnect from session;
Media recovery complete.
SQL>  SELECT ARCH.THREAD# “Thread”, ARCH.SEQUENCE# “Last Sequence Received”, APPL.SEQUENCE# “Last Sequence Applied”,
  2       (ARCH.SEQUENCE# – APPL.SEQUENCE#) “Difference” FROM (SELECT THREAD# ,SEQUENCE# FROM V$ARCHIVED_LOG
  3      WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME) FROM V$ARCHIVED_LOG GROUP BY THREAD#)) ARCH,
  4      (SELECT THREAD# ,SEQUENCE# FROM V$LOG_HISTORY WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME)
  5      FROM V$LOG_HISTORY GROUP BY THREAD#)) APPL WHERE ARCH.THREAD# = APPL.THREAD# ORDER BY 1;

    Thread Last Sequence Received Last Sequence Applied Difference
---------- ---------------------- --------------------- ----------
         1                    104                   104          0

SQL>

Ref: https://oracle-base.com/articles/18c/multitenant-copying-a-pdb-in-a-data-guard-environment-18c