What are three purposes of the RMAN “FROM” clause?
A.
to support PUSH-based active database duplication
B.
to support synchronization of a standby database with the primary database in a Data
environment
C.
To support PULL-based active database duplication
D.
To support file restores over the network in a Data Guard environment
E.
To support file recovery over the network in a Data Guard environment
Explanation:
E:
*With a control file autobackup,RMANcan recover the database even if the current controlfile,
recoverycatalog, and server parameter file are inaccessible.
* RMAN uses a recovery catalog to track filenames for all database files in a Data Guard
environment. A recovery catalog is a database schema used by RMAN to store metadata about
one or more Oracle databases. The catalog also records where the online redo logs, standby redo
logs, tempfiles, archived redo logs, backup sets, and image copies are created.
This questions doesn’t make sense as it’s unclear if they refer to the RMAN “FROM SERVICE”, “FROM ACTIVE DATABASE”, “FROM SCN”, “FROM SPFILE” or any of the may other FROM clauses.
Let’s assume they refer to “FROM SERVICE” (new in 12c), then the answer is B, D and E.
The “FROM ACTIVE DATABASE”, also enhanced in 12c, now allows PULL-based active database duplication based on backup sets. However, if you pick [C], you won’t find a permutation of 3 correct answers.
i aggree with you!
I think CDE!!
RMAN enables you to restore or recover files by connecting, over the network, to a physical standby database that contains the required files. You can restore an entire database, data files, control files, spfile, or tablespaces. Restoring files over the network is very useful in scenarios where you need to synchronize the primary and standby databases
Answer is B,D,E. all these 3 answers are correct RMAN ‘FROM SERVICE’clause
BCE
BCE
B D and E
BDE
http://www.toadworld.com/platforms/oracle/w/wiki/10565.recovery-manager-rman-enhancements-in-oracle-database-12c.aspx
Not C because is not needed FROM clause
“For active database duplication using backup sets (pull-based method), you must connect to the source database as TARGET using a net service name.”
http://docs.oracle.com/database/121/BRADV/rcmdupdb.htm#BRADV89938
The percise question was: “What are three purposes of the RMAN “FROM SERVICE” clause?”
BDE
CDE – OK
C – OK – new in 12c
Example 25-1 illustrates how to perform active duplication. RMAN uses the pull method
DUPLICATE TARGET DATABASE TO dupdb
FROM ACTIVE DATABASE
PASSWORD FILE
SPFILE
NOFILENAMECHECK;
http://docs.oracle.com/database/121/BRADV/rcmdupdb.htm#BRADV168
D,E – OK – new in 12c
As of Oracle Database 12c, RMAN lets you restore or recover files by connecting, over the network, to a physical standby database that contains the required files. You can restore an entire database, data files, control files, spfile, or tablespaces. Restoring files over the network is very useful in scenarios where you need to synchronize the primary and standby databases.
https://docs.oracle.com/database/121/SBYDB/rman.htm#SBYDB5457
RMAN restores database files, over the network, from a physical standby database by using the FROM SERVICE clause of the RESTORE command. The FROM SERVICE clause provides the service name of the physical standby database from which the files must be restored. During the restore operation, RMAN creates backup sets, on the physical standby database, of the files that need to be restored and then transfers these backup sets to the target database over the network.
Its C,D,E
Refresh a single datafile on the primary from the standby (or standby from primary)
The second option, which I think is an excellent new feature, makes restoring specific datafiles from a standby database easy. By using the new “FROM SERVICE” clause in the “RESTORE DATAFILE” command, in effect your standby database is your backup and the restore is done via the network.
oracle@gc12c ~]$ rman target sys/password@TESTDB auxiliary sys/password@DUPDB
Recovery Manager: Release 12.1.0.1.0 – Production on Wed Oct 15 10:26:58 2014
Copyright (c) 1982, 2013, Oracle and/or its affiliates. All rights reserved.
connected to target database: TESTDB (DBID=488428308732)
connected to auxiliary database: DUPDB (not mounted)
RMAN> run {
2> duplicate target database to DUPDB from active database
3> db_file_name_convert(‘TESTDB’,’DUPDB’);
4> }
Starting Duplicate Db at 15-OCT-2014 10:27:11
using target database control file instead of recovery catalog
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=20 device type=DISK
current log archived ……………….
CDE
BDE
BDE make sense if the question is as Djuro says:
The percise question was: “What are three purposes of the RMAN “FROM SERVICE” clause?”
from https://docs.oracle.com/database/121/BRADV/rcmdupdb.htm#BRADV89927
the difference between push and pull
When active database duplication is performed using image copies, after RMAN establishes a connection with the source database, the source database transfers the required database files to the auxiliary database. Using image copies may require additional resources on the source database. This method is referred to as the push-based method of active database duplication.
When RMAN performs active database duplication using backup sets, a connection is established with the source database and the auxiliary database. The auxiliary database then connects to the source database through Oracle Net Services and retrieves the required database files from the source database. This method of active database duplication is also to as the pull-based method.
PULL Method use Oracle Net Services.
PUSH Method use image copies
Answ CDE
CDE
DE are right follow the documentation link from nax: With “From Service” – restore / recover file in a DG environment over network
BCD are the answers in my opinion.
http://blog.dbvisit.com/oracle-database-12c-and-three-new-rman-features/
http://allthingsoracle.com/oracle-database-12c-rman-new-features-part1/
https://docs.oracle.com/database/121/SBYDB/rman.htm#SBYDB5457
RMAN restores database files, over the network, from a physical standby database by using the FROM SERVICE clause of the RESTORE command.
I think B is wrong. It’s a trick.
to support synchronization of a standby database with the primary database in a Data
environment
It’s DATA GUARD ENVIRONMENT, not DATA ENVIRONMENT.
So…
C,D,E are true.
BDE
From the docs
B
Recovering files by connecting, over the network, to physical standby database is useful in the following scenarios:
You need to roll-forward a physical standby database to make it in-sync with the primary database.
D
About Restoring Files Over the Network
RMAN restores database files, over the network, from a physical standby database by using the FROM SERVICE clause of the RESTORE command.
E
About Recovering Files Over the Network
RMAN can perform recovery by fetching an incremental backup, over the network, from a primary database and then applying this incremental backup to the physical standby database. RMAN is connected as TARGET to the physical standby database. The recovery process is optimized by restoring only the used data blocks in a data file. Use the FROM SERVICE clause to specify the service name of the primary database from which the incremental backup must be fetched.
A – wrong ( push = duplicate from active database)
C – wrong ( pull = duplicate from backupset)
B D E – correct, all possible with “FROM SERVICE” feature.
I think B,C,E are correct.
for sure B is correct;
recover database from service prim noredo using compressed backupset;
Restore the data file on the primary database by using the data file on the physical standby database as below :
RMAN> RESTORE DATAFILE ‘/u01/oradata/primary/chicago/users01.dbf’ FROM SERVICE boston ;
The question should be “FROM SERVICE” and so the final answer is:
BDE
From Oracle Documentation:
B -> “You can use the RECOVER … FROM SERVICE command to synchronize the data files on the physical standby database with those on the primary database.”
D -> “RMAN restores database files, over the network, from a physical standby database by using the FROM SERVICE clause of the RESTORE command.”
E -> “RMAN can perform recovery by fetching an incremental backup, over the network, from a primary database and then applying this incremental backup to the physical standby database. RMAN is connected as TARGET to the physical standby database. The recovery process is optimized by restoring only the used data blocks in a data file. Use the FROM SERVICE clause to specify the service name of the primary database from which the incremental backup must be fetched.”
B,D,E