Data Guard

Oracle Data Guard Chapter 3 - Implementing Standby Databases

Oracle Net Configuration for Data Guard

For this text, assume that the Oracle Net is using the tnsnames.ora file for node identification. On the primary site, the tnsnames.ora file should be configured to include the service name for each of the standby databases.

The listener.ora file on the primary site does not require any modification as long as it has a listener for itself. Similarly, on the standby site the listener file will not require any change.

Configure the tnsnames.ora file on the standby site to include the service name for the primary database. This is required for gap resolution using the "fetch archive log" method. A sample tnsnames.ora file from the primary and the standby site is given in the following example.

tnsnames.ora file on the primary site:

# Standby DB identification on Primary Site

Oracle Net Configuration

stdby1 =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST =  jrsp01  )(PORT = 1521))
    )
    (CONNECT_DATA =
      (SID = appsdb )
    )
  ) 

tnsnames.ora file on standby site

#Primary DB identification on Standby Site

primary1 =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST =  jrpr01  )(PORT = 1521))
    )
    (CONNECT_DATA =
      (SID = appsdb )
    )
  )

Oracle Net Configuration

The host, port, and sid parameters of the tnsnames file for the primary database on the standby site should match the host, port, and sid parameters of the listener file for the primary database on the primary site.  Similarly, the tnsnames setting for the standby site on the primary database should match the listener setting for the Oracle instance on the standby site.