1.How to check whether dataguard broker is enabled or not?Any command to check?
if this parameter is TRUE, it means DG Broker is started DMON is runinig.
show parameter dg_broker_start
2.What is the use of dataguard broker?and how it works?
if showed any dg configuration, it means broker - managed DG configuration s created.
DGGMRL / DGMGRL> show configuration
3.I have to do Auditing at user level trace in production database.what are the pre-requisits for it?You can use Fine-Grained Auditing for user.
What are the Steps to do user level auditing?
Any idea how much disk utilization after enabling auditing?