In which two cases is it possible to change the protection mode to maximum protection using Enterprise Manager Cloud Control?
A.
A snapshot standby database is the only standby database in the Data Guard configuration.
B.
A logical standby database is the only standby database in the data guard configuration.
C.
A far sync instance is the only Data Guard configuration member receiving redo in synchronous mode.
D.
Flashback is not enabled for either the primary database, the standby database, or both in the Data Guard configuration.
E.
The primary and standby databases are hosted on different operating systems.
Explanation:
Maximum protection mode requires the SYNC redo transport mode to be set on at least one standby database.
Note:
The Maximum protection mode ensures that no data loss will occur if the primary database fails. To provide this level of protection, the redo data needed to
recover a transaction must be written to both the online redo log and to the standby redo log on at least one synchronized standby database before the transaction
commits. To ensure that data loss cannot occur, the primary database will shut down, rather than continue processing transactions, if it cannot write its redo stream
to at least one synchronized standby database.http://www.oracle.com/technetwork/oem/framework-infra/wp-em12c-building-ha-level3-1631423.pdf
E is not checked, but Flashback database must be enabled on primary and standby
so B,D
5.5.1 Prerequisites for Enabling Fast-Start Failover
The following prerequisites must be met before the broker allows you to enable fast-start failover:
Ensure the broker configuration is operating in either maximum availability mode or maximum performance mode.
The selected standby database that will be the fast-start failover target must receive redo directly from the primary database or from a far sync instance.
Ensure that the standby database you choose to be the target of fast-start failover has its LogXptMode property set to either SYNC or FASTSYNC if you wish to enable fast-start failover in maximum availability mode, or to ASYNC if you wish to enable fast-start failover in maximum performance mode. The current primary database must have its LogXptMode property set accordingly and must have standby redo logs configured. Alternatively, use the RedoRoutes property to configure the redo transport mode for the target standby and the database currently in the primary role.
To use a far sync instance with fast-start failover, the far sync instance transport mode must be set to either SYNC or FASTSYNC and the target standby database transport mode must be set to ASYNC.
Enable Flashback Database and set up a fast recovery area on both the primary database and the target standby database.
See Oracle Database Backup and Recovery User’s Guide.
Install the DGMGRL command-line interface on the observer computer as described in Section 2.1.
Configure the TNSNAMES.ORA file on the observer system so that the observer is able to connect to the primary database and to the pre-selected target standby database.
If you are not using Oracle Clusterware or Oracle Restart, then you must create static service names so that the observer can automatically restart a database as part of reinstatement. See Section 2.2, “Prerequisites” for more information.
previous log comment belongs to another question… sorry about that 🙂
A is incorrect, as tested
DGMGRL> show configuration;
Configuration – config2
Protection Mode: MaxPerformance
Databases:
prim – Primary database
stdby1 – Snapshot standby database
Fast-Start Failover: DISABLED
Configuration Status:
SUCCESS
DGMGRL> edit configuration set protection mode as maxprotection;
Error: ORA-16627: operation disallowed since no standby databases would remain to support protection mode
(stdby1 logxptmode = sync)
C is incorrect, as farsync is not available in maxprotection
https://docs.oracle.com/database/121/SBYDB/create_fs.htm#SBYDB5443
5.3 Supported Protection Modes for Far Sync Instances
A far sync instance is supported in either maximum performance or maximum availability mode.
D is incorrect: flashback is not a requirement for maxprotection
on both databases:
SQL> select name, flashback_on from v$database;
NAME FLASHBACK_ON
——— ——————
PRIM NO
DGMGRL> edit configuration set protection mode as maxprotection;
Operation requires shutdown of instance “PRIM” on database “prim”
Shutting down instance “PRIM”…
Unable to connect to database
ORA-12560: TNS:protocol adapter error
Failed.
Warning: You are no longer connected to ORACLE.
Please complete the following steps to finish the operation:
shut down instance “PRIM” of database “prim”
start up instance “PRIM” of database “prim”
DGMGRL> exit
oracle@primserver:~$ dgmgrl /
DGMGRL for Linux: Version 11.2.0.4.0 – 64bit Production
Copyright (c) 2000, 2009, Oracle. All rights reserved.
Welcome to DGMGRL, type “help” for information.
Connected.
DGMGRL> show configuration
Configuration – config2
Protection Mode: MaxProtection
Databases:
prim – Primary database
stdby1 – Physical standby database
Fast-Start Failover: DISABLED
Configuration Status:
SUCCESS
B is correct for sure
DGMGRL> show configuration;
Configuration – config2
Protection Mode: MaxAvailability
Databases:
prim – Primary database
stdby1 – (*) Logical standby database
Fast-Start Failover: ENABLED
Configuration Status:
SUCCESS
B is correct and as flashback is not a requirement for max protection, D is also correct.
“B and D” or “B and E”?
B works for sure, my previous test was not correct:
Configuration – config
Protection Mode: MaxProtection
Databases:
prim – Primary database
stdby1 – Logical standby database
D (flashback) is not a requirement, see above, so also possible to go for max protection.
E? I can not test (my lab contains only linux machines) and no documentation found about that one.
about E… maybe the tricky part in the question is the ‘cloud control’:
Enterprise Manager can not be used for standby database creation or other administrative functions in any configuration where PLATFORM_IDs are not identical. Oracle recommends using the Data Guard Broker command line interface (DGMGRL) to administer mixed platform combinations from Oracle Database 11g onward and SQL*Plus command line for configurations that pre-date Oracle Database 11g.
https://support.oracle.com/epmos/faces/DocumentDisplay?%22&_afrLoop=351049760774417&id=413484.1&_afrWindowMode=0&_adf.ctrl-state=14n8u3qnxp_4
Brilliant note on heterogeneous DG configurations
Correct: D, E
B is completly wrong – maximum performance can be enabled only in physical standby
Correct: C, D
(if ‘different operating system’ == different platform (solaris/aix), not other, remote host – E is also wrong)
C is correct. EM cannot create far sync, but after creating far sync manually it is visible in EM configuration. EM can automaticaly change SYNC option if nessesary
C – This is wrong, I can have another database receiving data locally for example!
D – This is wrong, this is a best practice in data guard environment, for recovery for example; for a snapshot standby database; to help with failovers or switchovers;
Upgrading or Downgrading the Current Protection Mode
When you upgrade the current Data Guard protection mode (for example, you might want to upgrade from the maximum performance mode to the maximum availability mode), the broker shuts down and restarts the primary database. When you downgrade the current Data Guard protection mode, the database does not need to be restarted. Follow these recommendations when upgrading or downgrading the Data Guard protection mode:
When upgrading the protection mode, upgrade the log transport mode before you upgrade the overall protection mode. (The Data Guard GUI does this for you. See Section 5.4.3 for information.) At the time when you change the protection mode or reset the log transport mode of a standby database, the broker verifies that there is at least one standby database in the configuration that can support the requested grade of protection. If not, then the broker does not change the protection mode and returns an error.
When downgrading the protection mode, downgrade the protection mode first and then change the log transport mode (if necessary). The broker will not allow changing the log transport mode if doing so invalidates the current overall protection mode.
If you upgrade the protection mode from the maximum performance mode to the maximum protection mode, the broker ensures that there is at least one standby database using standby redo log files, and whose log transport mode is set to SYNC. If there are no standby databases in the configuration that meet these requirements, the request to upgrade the protection mode is rejected with an error.
It became possible to include different operating systems in a Data Guard configuration such as Windows and Linux.
Platform Migration, Hardware and O.S. Maintenance, Data Center Moves
Data Guard Redo Apply offers some flexibility for primary and standby databases to run on systems with different operating systems or hardware architectures. See My Oracle Support Note 413484.1 for details on mixed platform combinations supported in a Data Guard configuration3. Redo Apply can be used to facilitate technology refresh and some platform migrations with minimal downtime. Redo Apply can also be used to migrate to Automatic Storage Management and/or to move from single instance Oracle Databases to Oracle RAC, and for data center moves.
B, E
A,C, D are not correct. I have tested this in my lab env and also confirmed B is correct which left E alone so I took E. hahaha