Expdp/impdp directory, SCN, timestamp and consistent
As you know expdp is a logical backup not the physical one. It works in same version also you can expdp/impdp from lower to higher version. Oracle is very restricted expdp/impdp from higher to lower version.
There are few important things you should keep in mind.
1. Create directory, if already not, and ensure relevant user got grant to read, write the directory. This directory will be used to store the dump and log file.
CREATE OR REPLACE DIRECTORY DIR_NAME AS ‘/ora01/db/oracle/’;
GRANT READ, WRITE,EXECUTE ON DIRECTORY DIR_NAME TO scott;
2. Whenever you need to export online database/schema ensure you will use CONSISTENT=Y (in 11.2). If need you can use SCN or time using option FLASHBACK_TIME.
OR use below syntax. It will ensure your expdp will be consistent.
Note: It has been used many time successfully.
expdp \"/ as sysdba\" FLASHBACK_TIME=\"TO_TIMESTAMP\(TO_CHAR\(SYSDATE,\'YYYY-MM-DD HH24:MI:SS\'\),\'YYYY-MM-DD HH24:MI:SS\'\)\"