Oracle Data Guard Broker is a self sustaining configuration, which allows you to manage the Dataguard in more simple way. With the Broker you can start observer, perform switchover and failover. Also, you can change the Protection mode and define a redo log routes. As such, the Data Guard Broker provide a set of utilities to the DBA to manage the Data Guard in easier way.

You can see a brief architecture of the broker. The broker can be started from a 3rd server, but the configuration has to be sure with all instances. Because of that, it is recommended to be stored on the shared data location (ASM in our case)

Before we configure the Broker, we need again to prepare the standby and the primary, as there are some settings that needs to be fixed :)

To prepare the primary and standby, we have to move the password file to shared location and reset the destination parameters:

Note: As of Oracle Database 12c Release 1 (12.1), for all databases to be added to a broker configuration, any LOG_ARCHIVE_DEST_n parameters that have the SERVICE attribute set, but not the NOREGISTER attribute, must be cleared.

--Primary
----Unlock the Broker User
[oracle@enode01 ~]$
SQL> alter user sysdg identified by oracle_4U;
User altered.
SQL> alter user sysdg account unlock;
User altered.
SQL> exit;

----Password file Export:
[oracle@enode01 ~]$ scp /tmp/orapweastdb wnode03:/tmp/orapwwestdb
orapweastdb 100% 7680 7.5KB/s 00:00
[oracle@enode01 ~]$

----Log destination Reset
[oracle@enode01 ~]$ sqlplus / as sysdba
SQL> alter system set log_archive_dest_2='' scope=both sid='*';
System altered.
SQL> alter system set dg_broker_config_file1='+data/eastdb/dr1config.dat' scope=both sid='*';
System altered.
SQL> alter system set dg_broker_config_file2='+fra/eastdb/dr2config.dat' scope=both sid='*';
System altered.
SQL> alter system set dg_broker_start=true scope=both sid='*';
System altered.
SQL> exit


--Standby
----Password file import:
[grid@wnode03 ~]$ asmcmd pwcopy /tmp/orapwwestdb +data/westdb/orapwwestdb
copying /tmp/orapwwestdb -> +data/westdb/orapwwestdb 
[grid@wnode03 ~]$ su - oracle
[oracle@wnode03 ~]$ export ORACLE_SID=westdb1
[oracle@wnode03 ~]$ srvctl modify database -db westdb -pwfile +data/westdb/orapwwestdb

----Cancel Apply & Log destination Reset
[oracle@wnode03 ~]$ sqlplus / as sysdba
SQL> alter database recover managed standby database cancel;
Database altered.
SQL> alter system set log_archive_dest_2='' scope=both sid='*';
System altered.
SQL> alter system set dg_broker_config_file1='+data/westdb/dr1config.dat' scope=both sid='*';
System altered.
SQL> alter system set dg_broker_config_file2='+fra/westdb/dr2config.dat' scope=both sid='*';
System altered
SQL> alter system set dg_broker_start=true scope=both sid='*';
System altered.
SQL> exit
[oracle@wnode03 ~]$

----Verificaiton
[oracle@wnode03 ~]$ dgmgrl
DGMGRL for Linux: Version 12.1.0.2.0 - 64bit Production
Copyright (c) 2000, 2012, Oracle. All rights reserved.
Welcome to DGMGRL, type "help" for information.
DGMGRL> connect sysdg/oracle_4U@westdb
Connected as SYSDG.
DGMGRL> connect sysdg/oracle_4U@eastdb
Connected as SYSDG.
DGMGRL> exit
[oracle@wnode03 ~]$

The configuration is done on the primary and then the configuration is edited to include the standby as well:

[oracle@enode01 ~]$ dgmgrl
DGMGRL for Linux: Version 12.1.0.2.0 - 64bit Production
Copyright (c) 2000, 2012, Oracle. All rights reserved.
Welcome to DGMGRL, type "help" for information.
DGMGRL> connect sysdg/oracle_4U@eastdb
Connected as SYSDG.
DGMGRL> show configuration
ORA-16532: Data Guard broker configuration does not exist
Configuration details cannot be determined by DGMGRL
DGMGRL>
'eastdb' connect identifier is eastdb;
Configuration "dg_config" created with primary database "eastdb"
DGMGRL> show configuration
Configuration - dg_config
Protection Mode: MaxPerformance
Members:
eastdb - Primary database
Fast-Start Failover: DISABLED
Configuration Status:
DISABLED
DGMGRL>
DGMGRL> add database 'westdb' as connect identifier is westdb;
Database "westdb" added
DGMGRL> show configuration
Configuration - dg_config
Protection Mode: MaxPerformance
Members:
 eastdb - Primary database
   westdb - Physical standby database
Fast-Start Failover: DISABLED
Configuration Status:
DISABLED
DGMGRL>

Now that we have the configuration, we can change the configuration for the data guard:

DGMGRL> EDIT DATABASE 'eastdb' SET PROPERTY 'RedoRoutes' =
'(eastdb:westdb SYNC)';
Property "RedoRoutes" updated
DGMGRL> EDIT DATABASE 'westdb' SET PROPERTY 'RedoRoutes' =
'(westdb:eastdb SYNC)';
Property "RedoRoutes" updated
DGMGRL>
DGMGRL> edit database westdb set property MaxConnections=4;
DGMGRL> edit database eastdb set property MaxConnections=4;
DGMGRL>
DGMGRL> edit configuration set property CommunicationTimeout = 300; <- How many seconds before Broker decides Network timeout.
Property "communicationtimeout" updated
DGMGR
DGMGRL> edit configuration set property OperationTimeout = 600;  <- specifies the maximum amount of time the broker should wait for health check, get monitorable property, and set property
operations to complete
Property "operationtimeout" updated
DGMGRL>

DGMGRL> edit configuration set protection mode as MaxAvailability;
Succeeded.
DGMGRL
DGMGRL> enable configuration
Enabled.
DGMGRL> show configuration
Configuration - dg_config
   Protection Mode: MaxAvailability
   Members:
   eastdb - Primary database
     westdb - Physical standby database
Fast-Start Failover: DISABLED

Configuration Status:
SUCCESS (status updated 75 seconds ago)
DGMGRL>

From the Broker it is very easy to verify both Transportation & Apply

DGMGRL> show database eastdb
Database - eastdb
Role: PRIMARY
Intended State: TRANSPORT-ON
Instance(s):
eastdb1
eastdb2
Database Status:
SUCCESS
DGMGRL
DGMGRL>
DGMGRL> show database westdb
Database - westdb
Role: PHYSICAL STANDBY
Intended State: APPLY-ON
Transport Lag: 0 seconds (computed 1 second ago)
Apply Lag: 0 seconds (computed 1 second ago)
Average Apply Rate: 8.00 KByte/s
Real Time Query: OFF
Instance(s):
westdb1
westdb2 (apply instance)                 <- We ALWAYS HAVE only ONE apply instance.
Database Status:
SUCCESS