We have a PROD and standby already added in broker config. Now we have created another standby and adding it in broker.

If you receive below error message then you need to re create your broker configuration

[oracle@oel71002 ~]$ dgmgrl sys/'oracle'@ICP01DMA
DGMGRL for Linux: Release 12.2.0.1.0 - Production on Thu Oct 21 08:04:18 2021

Copyright (c) 1982, 2017, Oracle and/or its affiliates.  All rights reserved.

Welcome to DGMGRL, type "help" for information.

Connected to "ICP01DMA"
Connected as SYSDBA.
DGMGRL> DGMGRL> show configuration;

Configuration - ICP01DMA_DR

  Protection Mode: MaxPerformance
  Members:
  ICP01DMA - Primary database
    ICC01DMA - Physical standby database

Fast-Start Failover: DISABLED

Configuration Status:
SUCCESS   (status updated 3 seconds ago)

DGMGRL> ADD DATABASE 'ICC11DMA' AS CONNECT IDENTIFIER IS 'ICC11DMA' MAINTAINED AS PHYSICAL;
Error: ORA-16575: LOG_ARCHIVE_DEST_n parameter conflicts with the new member to be added

Failed.

delete the configuration files on all PROD and both standby databases

perform this step on ICP01DMAC,ICC01DMA,ICC11DMA


ALTER SYSTEM SET DG_BROKER_START=FALSE scope=both sid='*';
show parameter dg_broker_config_file
rm -rf broker11.dat
rm -rf broker12.dat
ALTER SYSTEM SET LOG_ARCHIVE_DEST_2='' scope=both sid='*';
ALTER SYSTEM SET LOG_ARCHIVE_DEST_3='' scope=both sid='*';

now enable on ICP01DMAC,ICC01DMA,ICC11DMA

ALTER SYSTEM SET DG_BROKER_START=TRUE scope=both sid='*';

now add the the configuartion again

[oracle@oel71002 ~]$ dgmgrl sys/'oracle'@ICP01DMA
DGMGRL for Linux: Release 12.2.0.1.0 - Production on Thu Oct 21 08:56:30 2021

Copyright (c) 1982, 2017, Oracle and/or its affiliates.  All rights reserved.

Welcome to DGMGRL, type "help" for information.
Connected to "ICP01DMA"
Connected as SYSDBA.
DGMGRL> show configuration
ORA-16532: Oracle Data Guard broker configuration does not exist

Configuration details cannot be determined by DGMGRL
DGMGRL> CREATE CONFIGURATION 'ICP01DMA_DR' AS PRIMARY DATABASE IS 'ICP01DMA' CONNECT IDENTIFIER IS 'ICP01DMA';
Configuration "ICP01DMA_DR" created with primary database "ICP01DMA"
DGMGRL> ADD DATABASE 'ICC01DMA' AS CONNECT IDENTIFIER IS 'ICC01DMA' MAINTAINED AS PHYSICAL;
Database "ICC01DMA" added
DGMGRL> ADD DATABASE 'ICC11DMA' AS CONNECT IDENTIFIER IS 'ICC11DMA' MAINTAINED AS PHYSICAL;
Database "ICC11DMA" added
DGMGRL> show configuration

Configuration - ICP01DMA_DR

  Protection Mode: MaxPerformance
  Members:
  ICP01DMA - Primary database
    ICC01DMA - Physical standby database
    ICC11DMA - Physical standby database

Fast-Start Failover: DISABLED

Configuration Status:
DISABLED

Enable the configuration

DGMGRL> ENABLE CONFIGURATION;
Enabled.
DGMGRL> show configuration

Configuration - ICP01DMA_DR

  Protection Mode: MaxPerformance
  Members:
  ICP01DMA - Primary database
    ICC01DMA - Physical standby database
    ICC11DMA - Physical standby database

Fast-Start Failover: DISABLED

Configuration Status:
SUCCESS   (status updated 19 seconds ago)

check status of dataguard

DGMGRL> show database "ICP01DMA"

Database - ICP01DMA

  Role:               PRIMARY
  Intended State:     TRANSPORT-ON
  Instance(s):
    ICP01DMA_1
    ICP01DMA_2

Database Status:
SUCCESS

DGMGRL> show database "ICC01DMA"

Database - ICC01DMA

  Role:               PHYSICAL STANDBY
  Intended State:     APPLY-ON
  Transport Lag:      0 seconds (computed 0 seconds ago)
  Apply Lag:          0 seconds (computed 0 seconds ago)
  Average Apply Rate: 416.00 KByte/s
  Real Time Query:    OFF
  Instance(s):
    ICC01DMA_1
    ICC01DMA_2

Database Status:
SUCCESS

DGMGRL> show database "ICC11DMA"

Database - ICC11DMA

  Role:               PHYSICAL STANDBY
  Intended State:     APPLY-ON
  Transport Lag:      0 seconds (computed 0 seconds ago)
  Apply Lag:          0 seconds (computed 0 seconds ago)
  Average Apply Rate: 5.94 MByte/s
  Real Time Query:    OFF
  Instance(s):
    ICC11DMA_1

Database Status:
SUCCESS