Oracle Datagaurd protection mode

Question

Hi,
I am working on Oracle 10.2.0.4 version on Solaris 9. I am using ASM for storage.
I have a DG setup, which i wanted to have one primary and 2 physical standby databases in MAX AVAILABILITY & MAX PERFORMANCE mode respecitively. I successfully setup the DG environment but would like to know if there is any type of verification or views that show that what standby is performing in what mode(v$dataguard_status,v$managed_standby, etc).
I have used the following log_archive_dest_n on the primary database entries for enabling the protection modes.
log_archive_dest_1                   LOCATION=USE_DB_RECOVERY_FILE_DEST VALID_FOR=(ALL_LOGFILES,A
                                              LL_ROLES) DB_UNIQUE_NAME=testdb_1
log_archive_dest_2                   SERVICE=testdb_2 OPTIONAL LGWR SYNC AFFIRM VALID_FOR=
                                              (ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=testdb_2
log_archive_dest_3                   SERVICE=testdb_3 OPTIONAL ARCH ASYNC AFFIRM VALID_FOR=
                                              (ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=testdb_3 I want to put
1) testdb_2 standby in MAXIMUM AVAILABILITY
2) testdb_3 standby in MAXIMUM PERFORMANCE
I built the testdb_2 physical standby first and upgraded the protection mode to MAXIMUM AVAILABILITY and is working fine (this is using real time log apply).
I built the testdb_3 phyisical standby second and just started the redo apply using "alter database recover managed standby database disconnect from session).
The whole DG setup is working fine with applying logs. But my main question is that when i give "select protection_mode, protection_level from v$database" on primary database, it shows only the "MAXIMUM AVAILABILITY" mode. Where do i see that MAXIMUM PERFORMANCE mode is existing too for this DG environment? Is there any view or do we just confirm this by seeing the managed recovery processes in the v$managed_standby view?
Any information or documentation links would be greatly appreciated.
Thanks,
Harris

Answer 1

Well, the information Uwe Hesse was provided is contradicting.
The protection mode is infact is a property of primary database but it the standby database, which defines it, which is directly related to the REDO TRANSPORT mode that we use. Because, when you upgrade the protection mode, you issue it on the primary database and use the standby clause in it.. as follows
alter database set standby database to maximize [protection|availability|performance]As mentioned before, i used the ARCH ASYNC mode for putting the second standby database in the MAXIMUM PERFORMANCE mode and my question was as where to see that this database is working in the PERFORMANCE protection mode. When i used the ARCH transport mode, the PROTECTION_MODE & PROTECTION_LEVEL on both Primary and 2 standby databases were showing as MAXIMUM AVAILABILITY mode. But the redo transport was working as expected in respective protection modes.
Since, we can use either LGWR ASYNC or ARCH ASYNC for MAXIMUM PERFORMANCE mode, i changed the redo transport mode for the 2nd standby database (testdb_3) and using real time apply using following command,
alter database recover managed standby database using current logfile through all switchover disconnect from session;the 2nd standby database(testdb_3) started showing that primary database is working in MAXIMUM PERfORMANCE mode in the control file where as the the 1st standby database (testdb_2) is showing that the primary database is working in the MAXIMUM AVAILABILITY mode. Following are the different protection status being shown by the primary & standby databases. I think this is the way you find what standby database is working in what protection mode respectively.
ON TESTDB_1 (PRIMARY DATABASE)
SQL> select protection_mode, protection_level from v$database;
PROTECTION_MODE      PROTECTION_LEVEL
MAXIMUM AVAILABILITY MAXIMUM AVAILABILITY
ON TESTDB_2 (STANDBY DATABASE using LGWR SYNC)
SQL> select protection_mode, protection_level from v$database;
PROTECTION_MODE      PROTECTION_LEVEL
MAXIMUM AVAILABILITY MAXIMUM AVAILABILITY
ON TESTDB_3 (STANDBY DATABASE using LWGR ASYNC)
SQL> select protection_mode, protection_level from v$database;
PROTECTION_MODE      PROTECTION_LEVEL
MAXIMUM PERFORMANCE  MAXIMUM PERFORMANCESo, the protection mode is not primarily a property of the primary database but it is defined by the standby database and the redo transport is part of it as well, which was my initial understanding too. Though the 2nd standby database is geographically distant from the primary database, as i am using the LGWR ASYNC, there is no impact on the primary database performance.
Correct me if i am wrong, well atleast i have shown you what Oracle Software is reporting regarding the status.
Thanks,
Harris.
Edited by: Harris2107 on Aug 25, 2010 2:07 PM