Configure second physical standby database - Oracle

I know there are various cases where in we have to setup a second physical standby database in our environments to have a redundant fail over strategy. I don't think there are enough documents out there that outline the process of adding the second standby database. I though I will share these steps today.

Parameters that should be considered while setting up the 2 node (single instance) standby Database.
In my case I will explain the parameters and their usage in setup. I am not going to explain the entire setup here. I you don't know how to setup physical standby database, please refer to this Physical_standby_setup.

At this point I am considering you know how to setup physical standby database and you are looking to add additional node to your setup.

Environments:

ORCL is PRIMARY INSTANCE and is on host        LINUX01   >> Primary Instance
ORCLSTB1 is STANDBY INSTANCE and is on host LINUX02  >> Standby already exists
ORCLSTB2 is STANDBY INSTANCE and is on host LINUX03  >>>  new instance to be added

PARAMETERS to be considered :

ARCHIVE_LOG_DEST_N   >>> these needs to be set to ship your logs to the new node,

This is a simple setup that can be used to makes sure all the three nodes will ship logs in case of switch over. In the below image I have configured such a way that each instance will send log files to other when they act as PRIMARY INSTANCE.

Note : I am using round robin process to ship logs between DB servers.

Example of Archive_Log_Dest setup

Adding Archive_log Dests:

ON DB SERVER Linux01 (ORCLPRIM):

alter system set log_archive_config='dg_config=(ORCL,ORCLSTB1,ORCLSTB2)';

ALTER SYSTEM SET LOG_ARCHIVE_DEST_2='SERVICE=ORCLSTB1 NOAFFIRM ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=ORCLSTB1';

ALTER SYSTEM SET LOG_ARCHIVE_DEST_STATE_2=ENABLE;

ALTER SYSTEM SET LOG_ARCHIVE_DEST_3='SERVICE=ORCLSTB2 NOAFFIRM ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=ORCLSTB2';

ALTER SYSTEM SET LOG_ARCHIVE_DEST_STATE_3=ENABLE;

ON DB SERVER Linux02 (ORCLSTB1):

alter system set log_archive_config='dg_config=(ORCL,ORCLSTB1,ORCLSTB2)';

ALTER SYSTEM SET LOG_ARCHIVE_DEST_2='SERVICE=ORCLPRIM NOAFFIRM ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=ORCL';

ALTER SYSTEM SET LOG_ARCHIVE_DEST_STATE_2=ENABLE;

ALTER SYSTEM SET LOG_ARCHIVE_DEST_3='SERVICE=ORCLSTB2 NOAFFIRM ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=ORCLSTB2';

ALTER SYSTEM SET LOG_ARCHIVE_DEST_STATE_3=ENABLE;

ON DB SERVER Linux03 (ORCLSTB2):

alter system set log_archive_config='dg_config=(ORCL,ORCLSTB1,ORCLSTB2)';

ALTER SYSTEM SET LOG_ARCHIVE_DEST_2='SERVICE=ORCLPRIM NOAFFIRM ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=ORCL';

ALTER SYSTEM SET LOG_ARCHIVE_DEST_STATE_2=ENABLE;

ALTER SYSTEM SET LOG_ARCHIVE_DEST_3='SERVICE=ORCLSTB1 NOAFFIRM ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=ORCLSTB1';

ALTER SYSTEM SET LOG_ARCHIVE_DEST_STATE_3=ENABLE;

OTHER PARAMETER FILE SETTINGS: 

PFILE DB_* PARAMETERS on DB SERVER1 (Linux01)(ORCL): 

log_archive_config='dg_config=(ORCL,ORCLSTB1,ORCLSTB2)';  >> This is to tell oracle that what all instances are part of this config

*.db_file_name_convert='/ORCLSTB1/','/ORCL/','/ORCLSTB2/','/ORCL/'        -- > add both servers so oracle knows where to create file. 

*.db_name='ORCL'  ### same across all Databases 

*.db_unique_name='ORCL'  ### Unique across each Database 

FAL_SERVER=ORCLSTB1, ORCLSTB2-- > add both servers so oracle knows where to get the archive files from incase of switchover. 

FAL_CLIENT=ORCLThis is always the Current DB server typically standby DB. This is ignored when the DB is in Primary mode 

PFILE DB_* PARAMETERS on DB SERVER2 (Linux02)(ORCLSTB1): 

log_archive_config='dg_config=(ORCL,ORCLSTB1,ORCLSTB2)';
*.db_file_name_convert='/ORCL/','/ORCLSTB1/','/ORCLSTB2/','/ORCLSTB1/' 

*.db_name='ORCL'### same across all Databases 

*.db_unique_name='ORCLSTB1'                    ### Unique across each Database 

*.FAL_CLIENT=STANDBY_SERVER 

*.FAL_SERVER=PRIMARY_SERVERS 

PFILE DB_* PARAMETERS on DB SERVER3 (Linux03)(ORCLSTB2): 

log_archive_config='dg_config=(ORCL,ORCLSTB1,ORCLSTB2)';
*.db_file_name_convert='/ORCLSTB1/','/ORCLSTB2/','/ORCL/','/ORCLSTB2/' 

*.db_name='ORCL'### same across all Databases 

*.db_unique_name='ORCLSTB2'                 ### Unique across each Database 

*.FAL_CLIENT=STANDBY_SERVER 

*.FAL_SERVER=PRIMARY_SERVERS