Protection Modes in Oracle Dataguard

We have 3 Protection modes available in Oracle DataGuard

1. Maximum Performance :

This is the default protection mode. It provides the highest level of data protection that is possible

without affecting the performance of a primary database. This is accomplished by allowing transactions to commit as soon as all redo data generated by those transactions has been written to the online log. 

2. Maximum Availability :

This protection mode provides the highest level of data protection that is possible without compromising the availability of a primary database. Transactions do not commit until all redo data needed to recover those transactions has been written to the online redo log and to at least one standby database.

3. Maximum Protection :

This 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 at least one standby database before the transaction commits. To ensure that data loss cannot occur, the primary database will shut down, rather than continue processing transactions.

How to create Oracle directory?

Database Directories are required to read/write to a filesystem location from plsql code.

Below is the syntax to create database directory

SQL> create directory PLSQL_DIR AS '/oratmp/code';

Directory created.

Grant Read/write privileges to Required Schema

SQL> GRANT READ,WRITE ON DIRECTORY PLSQL_DIR TO APPS;

Grant succeeded.

Oracle Recovery Manager Troubleshooting ::ORA-27211: Failed to load Media Management Library

This is an error during Database Clone using RMAN.

I was trying to restore database using RMAN Backup

RMAN-00571: ===========================================================

RMAN-00569: ===============
ERROR MESSAGE STACK FOLLOWS ===============

RMAN-00571: ===========================================================

RMAN-03002: failure of Duplicate Db command
RMAN-05501: aborting duplication of target database

RMAN-03009: failure of allocate command on ORA_AUX_SBT_TAPE_1 channel 
ORA-19554: error allocating device, device type: SBT_TAPE, device name:

ORA-27211: Failed to load Media Management Library

Additional information: 

Cause: Backup Configuration was modified.

Solution:
Use the below command to Resolve the error and continue with Database Restore

rman auxiliary / 
run
{
allocate auxiliary channel c1 type disk;
allocate auxiliary channel c2 type disk;
duplicate database to 'DEV' backup location '/Daily_Backup/Backup_16042018';
}
exit;
EOF