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November 12, 2015 / Shivananda Rao P

Cascading Standby Database in 11g

This article demonstrates on the steps involved in configuring a cascaded physical standby database. A cascading standby environment is one wherein a standby receives the redo data directly from the primary database and then transmits it to the other cascaded standby databases.

 

This method offloads the primary in transmitting the redo to multiple standbys, instead it just transmits to the single cascading standby which in turn cascades to multiple standbys. Also, the redo received by the cascading physical standby database can cascade it to upto 30 physical or logical or snapshot standbys.

 

After speaking about the advantages of “Cascaded Standby Databases”, it also has certain restrictions:

 

1. A cascading environment cannot be used if the primary database is a RAC configuration. (This restriction has been removed from 11.2.0.2)

 

2. If dataguard broker is configured, then cascading redo to other standbys is not allowed.

 

3. A logical standby database or a snapshot standby database cannot act as a Cascading standby database. In other words, a logical or a snapshot standby cannot retransmit the redo data to a cascaded standby database.

 

4. Since the redo data on a cascaded standby is received from a cascading standby database and not directly from the primary database, there is always a lag at the cascaded standby database. The redo will be received only when the current redo on the cascading standby will be archived.

 

To minimize the lag, Standby Redo Logs are needed while implementing Cascaded Standbys to make use of the Real Time Apply feature.

 

Let’s move on with the steps involved in achieving this. This primary database used here is a standalone database with OMF managed datafiles through ASM and the cascading as well as cascaded standbys too are standalone databases with OMF managed datafiles through ASM. Also, this post assumes that a physical standby is setup for the primary which would be acting as a cascading standby and the standby redo logs are configured on both primary and the cascading standby database and it’s creation is not outlined here.

 

Environment:

Primary Site:

DB Name        : srprim
DB Unique name : srprim
Hostname       : ora1-1

 

Cascading Site:

 

DB Name        : srprim
DB Unique Name : srpstb
Hostname       : ora1-2

 

Cascaded Site:

DB Name        : srprim
DB Unique Name : srcstb
Hostname       : ora1-3

 

The configuration uses “Flash Recovery Area” on all (primary, cascading and cascaded standby databases). To graphically help you understand, the cascaded environment looks as below:

SRPRIM    —– >    SRPSTB    —– >   SRCSTB

 

Cascade_standby

 

Create a pfile for the cascaded database “srcstb” with all the required parameters. Below is how the PFILE for the “srcstb” instance looks.

 

[oracle@ora1-3 ~]$ cat /u02/initsrcstb.ora
srcstb.__db_cache_size=381681664
srcstb.__java_pool_size=4194304
srcstb.__large_pool_size=4194304
srcstb.__pga_aggregate_target=381681664
srcstb.__sga_target=566231040
srcstb.__shared_io_pool_size=0
srcstb.__shared_pool_size=159383552
srcstb.__streams_pool_size=0
*.audit_file_dest='/u01/app/oracle/admin/srcstb/adump'
*.audit_trail='DB'
*.compatible='11.2.0.0.0'
*.control_files='+DATA1','+FRA1'
*.core_dump_dest='/u01/app/oracle/diag/rdbms/srcstb/srpstb/cdump'
*.db_block_size=8192
*.db_create_file_dest='+DATA1'
*.db_domain=''
*.db_file_name_convert='+DATA_NEW','+DATA1'
*.db_name='srprim'
*.db_recovery_file_dest='+FRA1'
*.db_recovery_file_dest_size=4032M
*.db_unique_name='srcstb'
*.diagnostic_dest='/u01/app/oracle'
*.dispatchers='(PROTOCOL=TCP) (SERVICE=srcstbXDB)'
*.fal_server='srprim'
*.log_archive_dest_1='location=use_db_recovery_file_dest valid_for=(all_logfiles,all_roles) db_unique_name=srcstb'
*.log_buffer=5820416# log buffer update
*.log_file_name_convert='+FRA_NEW','+FRA1'
*.memory_target=904M
*.open_cursors=300
*.optimizer_dynamic_sampling=2
*.optimizer_mode='ALL_ROWS'
*.plsql_warnings='DISABLE:ALL'# PL/SQL warnings at init.ora
*.processes=150
*.query_rewrite_enabled='TRUE'
*.remote_login_passwordfile='EXCLUSIVE'
*.result_cache_max_size=2336K
*.skip_unusable_indexes=TRUE

Make sure that the TNS entries for SRPRIM, SRPSTB and SRCSTB exist on each of the 3 (ora1-1, ora1-2 and ora1-3) servers.

 


SRPRIM =
(DESCRIPTION =
  (ADDRESS = (PROTOCOL = TCP)(HOST = ora1-1.mydomain)(PORT = 1521))
  (CONNECT_DATA =
     (SERVER = DEDICATED)
     (SERVICE_NAME = srprim)
  )
)

SRPSTB =
(DESCRIPTION =
  (ADDRESS = (PROTOCOL = TCP)(HOST = ora1-2.mydomain)(PORT = 1521))
  (CONNECT_DATA =
     (SERVER = DEDICATED)
     (SERVICE_NAME = srpstb)
  )
)

SRCSTB =
(DESCRIPTION =
  (ADDRESS = (PROTOCOL = TCP)(HOST = ora1-3.mydomain)(PORT = 1521))
  (CONNECT_DATA =
   (SERVER = DEDICATED)
   (SERVICE_NAME = srcstb)
  )
)

Add a static entry about the details of SRCSTB instance to the listener.ora file on the cascaded standby host “ora1-3”.

 

SID_LIST_LISTENER =
(SID_LIST =
  (SID_DESC =
     (ORACLE_HOME = /u01/app/oracle/product/11.2.0.2/db1)
     (SID_NAME = srcstb)
  )
)

 

Copy the password file from “srpstb” to the cascading standby site “ora1-3” and rename it according to the cascading standby database name “srcstb”.

 

[oracle@ora1-2 ~]$ scp /u01/app/oracle/product/11.2.0.2/db_1/dbs/orapwsrpstb oracle@ora1-3:/u01/app/oracle/product/11.2.0.2/db1/dbs/orapwsrcstb
The authenticity of host 'ora1-3 (192.168.56.107)' can't be established.
RSA key fingerprint is 26:01:48:55:e9:ae:ae:9a:f9:fd:38:db:29:b7:fa:4e.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'ora1-3' (RSA) to the list of known hosts.
oracle@ora1-3's password:
orapwsrpstb 100% 1536 1.5KB/s 00:00
[oracle@ora1-2 ~]$

 

Start the instance “srcstb” in nomount stage using the PFILE created earlier.

 

[oracle@ora1-3 ~]$ sqlplus sys/oracle@srcstb as sysdba

SQL*Plus: Release 11.2.0.2.0 Production on Sat Aug 8 10:04:49 2015

Copyright (c) 1982, 2010, Oracle. All rights reserved.

Connected to an idle instance.

SYS@srcstb> startup nomount
ORA-32004: obsolete or deprecated parameter(s) specified for RDBMS instance
ORACLE instance started.

Total System Global Area 943669248 bytes
Fixed Size 2232128 bytes
Variable Size 553648320 bytes
Database Buffers 381681664 bytes
Redo Buffers 6107136 bytes

Current settings of log shipping parameters on my primary database “srprim” is as :

SYS@srprim> select name,value from v$parameter where name in ('log_archive_dest_1','log_archive_dest_2');

NAME                  VALUE
--------------------- -----------------------------------------------------------------------
log_archive_dest_1    location=use_db_recovery_file_dest valid_for=(all_logfiles,all_roles) d                      b_unique_name=srprim
log_archive_dest_2    service="srpstb", LGWR SYNC AFFIRM delay=0 optional compression=disable                      max_failure=0 max_connections=1 reopen=300 db_unique_name="srpstb" net_                      t imeout=30, valid_for=(all_logfiles,primary_role)

It ships redo data only to the cascading standby database “srpstb”. Also, on “srpstb”, there is no redo shipment parameter configured to ship it to “srcstb”.

The details are as below for “srpstb” instance.

 

[oracle@ora1-2 ~]$ sqlplus sys/oracle@srpstb as sysdba

SQL*Plus: Release 11.2.0.2.0 Production on Sat Aug 8 10:06:32 2015

Copyright (c) 1982, 2010, Oracle. All rights reserved.

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, Automatic Storage Management, OLAP, Data Mining
and Real Application Testing options

SYS@srpstb> select status,instance_name,database_role from v$database,v$instance;

STATUS       INSTANCE_NAME    DATABASE_ROLE
------------ ---------------- ----------------
MOUNTED      srpstb           PHYSICAL STANDBY

SYS@srpstb> select name,value from v$parameter where name in ('log_archive_dest_1','log_archive_dest_2');

NAME                VALUE
------------------- -------------------------------------------------------------------------
log_archive_dest_1  location=use_db_recovery_file_dest valid_for=(all_logfiles,all_roles) db_                    unique_name=srpstb
log_archive_dest_2  service=srprim SYNC valid_for=(all_logfiles,primary_role) db_unique_name=                    srprim
SYS@srpstb> select process,status,sequence# from v$managed_standby;

PROCESS   STATUS         SEQUENCE#
--------- ------------   ----------
ARCH      CONNECTED      0
ARCH      CONNECTED      0
ARCH      CONNECTED      0
ARCH      CLOSING        90
RFS       IDLE           0
RFS       IDLE           0
RFS       IDLE           0
RFS       IDLE           91
MRP0      WAIT_FOR_LOG   91

9 rows selected.

It can be noticed above that, MRP is currently running on “srpstb” waiting for log sequence 91.
Now, create the standby database “srcstb” using RMAN “active” duplication method. Note that, the duplication is being carried out with “srpstb” as a target database. In other words, I’m using a standby database as a source to perform RMAN active duplicate to create a new standby. This option is available from 11.2.0.2 version, provided there are pre-requisties patches that need to be applied on both source and target environment.

 

If RMAN active duplicate with source as standby is not feasible or un-supported for your version, then you can go with “RMAN active duplicate” from primary database or use the traditional way of RMAN backup restore and recovery to create the cascaded standby “srcstb”.

 

[oracle@ora1-3 dbs]$ rman target sys/oracle@srpstb auxiliary sys/oracle@srcstb

Recovery Manager: Release 11.2.0.2.0 - Production on Sun Aug 16 11:46:55 2015

Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved.

connected to target database: SRPRIM (DBID=298418015, not open)
connected to auxiliary database: SRPRIM (not mounted)

RMAN> duplicate target database for standby from active database nofilenamecheck;

Starting Duplicate Db at 16-AUG-15
using target database control file instead of recovery catalog
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=24 device type=DISK

contents of Memory Script:
{
backup as copy reuse
targetfile '/u01/app/oracle/product/11.2.0.2/db_1/dbs/orapwsrpstb' auxiliary format
'/u01/app/oracle/product/11.2.0.2/db1/dbs/orapwsrcstb' ;
}
executing Memory Script

Starting backup at 16-AUG-15
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=40 device type=DISK
Finished backup at 16-AUG-15

contents of Memory Script:
{
backup as copy current controlfile for standby auxiliary format '+DATA1/srcstb/controlfile/current.267.887888833';
restore clone controlfile to '+FRA1/srcstb/controlfile/current.267.887888835' from
'+DATA1/srcstb/controlfile/current.267.887888833';
sql clone "create spfile from memory";
shutdown clone immediate;
startup clone nomount;
sql clone "alter system set control_files =
''+DATA1/srcstb/controlfile/current.267.887888833'', ''+FRA1/srcstb/controlfile/current.267.887888835'' comment=
''Set by RMAN'' scope=spfile";
shutdown clone immediate;
startup clone nomount;
}
executing Memory Script

Starting backup at 16-AUG-15
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
copying standby control file
output file name=/u01/app/oracle/product/11.2.0.2/db_1/dbs/snapcf_srpstb.f tag=TAG20150816T114714 RECID=18 STAMP=887888836
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:03
Finished backup at 16-AUG-15

Starting restore at 16-AUG-15
using channel ORA_AUX_DISK_1

channel ORA_AUX_DISK_1: copied control file copy
Finished restore at 16-AUG-15

sql statement: create spfile from memory

Oracle instance shut down

connected to auxiliary database (not started)
Oracle instance started

Total System Global Area 943669248 bytes

Fixed Size 2232128 bytes
Variable Size 553648320 bytes
Database Buffers 381681664 bytes
Redo Buffers 6107136 bytes

sql statement: alter system set control_files = ''+DATA1/srcstb/controlfile/current.267.887888833'', ''+FRA1/srcstb/controlfile/current.267.887888835'' comment= ''Set by RMAN'' scope=spfile

Oracle instance shut down

connected to auxiliary database (not started)
Oracle instance started

Total System Global Area 943669248 bytes

Fixed Size 2232128 bytes
Variable Size 553648320 bytes
Database Buffers 381681664 bytes
Redo Buffers 6107136 bytes

contents of Memory Script:
{
sql clone 'alter database mount standby database';
}
executing Memory Script

sql statement: alter database mount standby database
RMAN-05529: WARNING: DB_FILE_NAME_CONVERT resulted in invalid ASM names; names changed to disk group only.

contents of Memory Script:
{
set newname for tempfile 1 to
"+data1";
set newname for tempfile 2 to
"+data1";
switch clone tempfile all;
set newname for datafile 1 to
"+data1";
set newname for datafile 2 to
"+data1";
set newname for datafile 3 to
"+data1";
set newname for datafile 4 to
"+data1";
backup as copy reuse
datafile 1 auxiliary format
"+data1" datafile
2 auxiliary format
"+data1" datafile
3 auxiliary format
"+data1" datafile
4 auxiliary format
"+data1" ;
}
executing Memory Script

executing command: SET NEWNAME

executing command: SET NEWNAME

renamed tempfile 1 to +data1 in control file
renamed tempfile 2 to +data1 in control file

executing command: SET NEWNAME

executing command: SET NEWNAME

executing command: SET NEWNAME

executing command: SET NEWNAME

Starting backup at 16-AUG-15
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00001 name=+DATA_NEW/srpstb/datafile/system.258.882637005
output file name=+DATA1/srcstb/datafile/system.276.887888881 tag=TAG20150816T114801
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:35
channel ORA_DISK_1: starting datafile copy
input datafile file number=00002 name=+DATA_NEW/srpstb/datafile/sysaux.259.882637031
output file name=+DATA1/srcstb/datafile/sysaux.275.887888917 tag=TAG20150816T114801
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:25
channel ORA_DISK_1: starting datafile copy
input datafile file number=00003 name=+DATA_NEW/srpstb/datafile/undotbs1.260.882637057
output file name=+DATA1/srcstb/datafile/undotbs1.274.887888941 tag=TAG20150816T114801
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:03
channel ORA_DISK_1: starting datafile copy
input datafile file number=00004 name=+DATA_NEW/srpstb/datafile/users.261.882637061
output file name=+DATA1/srcstb/datafile/users.273.887888945 tag=TAG20150816T114801
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:01
Finished backup at 16-AUG-15

contents of Memory Script:
{
switch clone datafile all;
}
executing Memory Script

datafile 1 switched to datafile copy
input datafile copy RECID=18 STAMP=887888946 file name=+DATA1/srcstb/datafile/system.276.887888881
datafile 2 switched to datafile copy
input datafile copy RECID=19 STAMP=887888946 file name=+DATA1/srcstb/datafile/sysaux.275.887888917
datafile 3 switched to datafile copy
input datafile copy RECID=20 STAMP=887888946 file name=+DATA1/srcstb/datafile/undotbs1.274.887888941
datafile 4 switched to datafile copy
input datafile copy RECID=21 STAMP=887888946 file name=+DATA1/srcstb/datafile/users.273.887888945
Finished Duplicate Db at 16-AUG-15

RMAN> exit

Recovery Manager complete.
[oracle@ora1-3 dbs]$

Now that the standby is created, set the log shipping parameters on the primary and the cascading standby databases accordingly.

On the primary, I set “log_archive_dest_3” parameter to ship the redo to “srcstb”. Of-course, the “log_archive_dest_state_3” would be deffered as I do not want the primary to ship the redo to the cascaded standby.

By doing so, the concept of “cascaded standby” does not come into picture.

I set “log_archive_dest_3” on primary to ship the redo to “srcstb”, so that, if in case, “srpstb” goes down or is unreachable, then there wouldn’t be any DR database. So, as an alternate option, I have set this parameter.

 

[oracle@ora1-1 admin]$ sqlplus sys/oracle@srprim as sysdba

SQL*Plus: Release 11.2.0.2.0 Production on Sun Aug 16 12:16:14 2015

Copyright (c) 1982, 2010, Oracle. All rights reserved.

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, Automatic Storage Management, OLAP, Data Mining
and Real Application Testing options

SYS@srprim> sho parameter dest_3

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_create_online_log_dest_3          string
log_archive_dest_3                   string
log_archive_dest_30                  string
log_archive_dest_31                  string
SYS@srprim>
SYS@srprim> alter system set log_archive_dest_3='service=srcstb valid_for=(standby_logfiles,standby_role) db_unique_name=srcstb';

System altered.

SYS@srprim> alter system set log_archive_dest_state_3=defer;

System altered.
SYS@srprim> sho parameter log_archive_dest_3

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
log_archive_dest_3                   string      service=srcstb valid_for=(onli
                                                 ne_logfiles,primary_role) db_u
                                                 nique_name=srcstb
log_archive_dest_30                  string
log_archive_dest_31                  string
SYS@srprim>
SYS@srprim>
SYS@srprim> sho parameter dest_state_3

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
log_archive_dest_state_3             string      DEFER
log_archive_dest_state_30            string      enable
log_archive_dest_state_31            string      enable
SYS@srprim>

Set the log_archive_config parameter on all the 3 databases to host the value of all 3 database unique names.

 

SYS@srprim> alter system set log_archive_config='DG_CONFIG=(srprim,srpstb,srcstb)';

System altered.

SYS@srprim> sho parameter log_archive_config

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
log_archive_config                   string      DG_CONFIG=(srprim,srpstb,srcst
                                                 b)

On the cascading standby database “srpstb”, set the parameter “log_archive_dest_3” to ship the redo data to the cascaded standby database “srcstb”.

[oracle@ora1-2 admin]$ sqlplus sys/oracle@srpstb as sysdba

SQL*Plus: Release 11.2.0.2.0 Production on Sun Aug 16 12:20:20 2015

Copyright (c) 1982, 2010, Oracle. All rights reserved.

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, Automatic Storage Management, OLAP, Data Mining
and Real Application Testing options

SYS@srpstb> sho parameter dest_2

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_create_online_log_dest_2          string      
log_archive_dest_2                   string      service=srprim val                                                                           id_for=(online_logfiles,primary_role) db_u
                                                 nique_name=srprim

SYS@srpstb> show parameter dest_3

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_create_online_log_dest_3          string      
log_archive_dest_3                   string
SYS@srpstb>
SYS@srpstb> alter system set log_archive_dest_3='service=srcstb valid_for=(standby_logfiles,standby_role) db_unique_name=srcstb';

System altered.
SYS@srpstb> alter system set log_archive_config='DG_CONFIG=(srprim,srpstb,srcstb)';

System altered.

On “srcstb”, set the log_archive_config parameter and “fal_server” parameter.
FAL_SERVER on “srcstb” should use the NET alias name of “srpstb” as it would be receiving the redo data from “srpstb” database.

 

[oracle@ora1-3 dbs]$ sqlplus sys/oracle@srcstb as sysdba

SQL*Plus: Release 11.2.0.2.0 Production on Sun Aug 16 12:14:58 2015

Copyright (c) 1982, 2010, Oracle. All rights reserved.

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, Automatic Storage Management, OLAP, Data Mining
and Real Application Testing options

SYS@srcstb>
SYS@srcstb> select status,instance_name,database_role,open_mode from v$database,v$instance;

STATUS       INSTANCE_NAME    DATABASE_ROLE    OPEN_MODE
------------ ---------------- ---------------- --------------------
MOUNTED      srcstb           PHYSICAL STANDBY MOUNTED

SYS@srcstb> alter system set log_archive_config='DG_CONFIG=(srprim,srpstb,srcstb)';

System altered.

SYS@srcstb> alter system set fal_server='srpstb';

System altered.

SYS@srcstb> alter system set fal_client='srcstb';

System altered.

In this environment, RMAN automatically creates the Standby Redo logs after the duplication as they were configured previously and existed on the primary and cascading standby databases. Verify there existance on the cascaded standby and if in case, do not exist, then create them manually.

Start the Managed Recovery Process on the cascaded standby database “srcstb”.

 

SYS@srcstb> alter database recover managed standby database disconnect from session using current logfile;

Database altered.

SYS@srcstb> select process,status,sequence# from v$managed_standby;

PROCESS   STATUS       SEQUENCE#
--------- ------------ ----------
ARCH      CONNECTED    0
ARCH      CONNECTED    0
ARCH      CONNECTED    0
ARCH      CLOSING      215
MRP0      WAIT_FOR_LOG 217
RFS       IDLE         0
RFS       IDLE         0
RFS       IDLE         0

8 rows selected.

Verify the sync status of cascading standby “srpstb” and cascaded standby “srcstb” databases.
On the primary, the latest archive sequence is generated is 226:

 

SYS@srprim> select status,instance_name,database_role from v$database,v$instance;

STATUS       INSTANCE_NAME    DATABASE_ROLE
------------ ---------------- ----------------
OPEN         srprim           PRIMARY

SYS@srprim> select max(sequence#) from v$archived_log;

MAX(SEQUENCE#)
--------------
226

On the cascading standby SRPSTB, the last sequence applied is 226.

 

SYS@srpstb> select status,instance_name,database_role from v$database,v$instance;

STATUS       INSTANCE_NAME    DATABASE_ROLE
------------ ---------------- ----------------
MOUNTED      srpstb           PHYSICAL STANDBY

SYS@srpstb> select max(sequence#) from v$archived_log where applied='YES';

MAX(SEQUENCE#)
--------------
226

Similarly, on the cascaded standby SRCSTB, the last sequence generated is 225.

 

SYS@srcstb> select status,instance_name,database_role from v$database,v$instance;

STATUS       INSTANCE_NAME    DATABASE_ROLE
------------ ---------------- ----------------
MOUNTED      srcstb           PHYSICAL STANDBY

SYS@srcstb> select max(sequence#) from v$archived_log where applied='YES';

MAX(SEQUENCE#)
--------------
225

COPYRIGHT

© Shivananda Rao P, 2012, 2013, 2014, 2015. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Shivananda Rao and http://www.shivanandarao-oracle.com with appropriate and specific direction to the original content.

 

 

DISCLAIMER

The views expressed here are my own and do not necessarily reflect the views of any other individual, business entity, or organization. The views expressed by visitors on this blog are theirs solely and may not reflect mine.

 

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2 Comments

Leave a Comment
  1. sachinsharma609 / Nov 16 2015 4:32 pm

    Hello Shiv ,
    I have cascade standby in our environment for two node rac. scenario is like that –

    two node rac primary –> two node rac standby –> standalone standby (cascade)

    IS cascade standby for two node rac is a standalone is possible?

  2. Shivananda Rao P / Nov 17 2015 5:32 am

    Hi Sachin, if you are using 11.2.0.2 or a higher version, then the restriction has been removed. You can have a cascading standby built for a RAC primary and is supported irrespective of whether your cascaded standby is a standalone or RAC.

    Regards,
    Shivananda

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