In what state is the Oracle database on the standby system?

Database should be  mounted/open.

Extract from NBU for Oracle manual:

Troubleshooting the browser interface and wizards
If you do not see the Oracle instance in your Backup, Archive, and Restore interface,
verify the following:
■ A NetBackup for Oracle license is installed on the master server.
■ For browsing in the restore window, the policy type must be set to Oracle.
Perform the following actions to change the client policy type:
■ On the Actions menu, select Specify NetBackup Machines and Policy
type.
■ In the Policy type drop-down list, select Oracle.
■ Click OK.
■ The oratab file is in the correct location (/etc/oratab or
/var/opt/oracle/oratab) and contains all of the available Oracle SIDs.
Although Oracle allows the use of wild cards in the oratab file, the NetBackup
BAR GUI requires that each SID be specified.
If you have trouble connecting to the Oracle database, verify the following:
■ Make sure that the database is in a mount state or an open state.
■ Make sure that your login ID and password have Oracle SYSDBA privileges.
Initially, NetBackup for Oracle attempts OS Authentication to log on. If that
fails, you are prompted for a user name, password, and an optional Transparent
Network Substrate (TNS) alias. The user name and password you enter must
have SYSDBA privileges.

Hi Marianne,

Thanks for your reply, My database is in a mount state. I think all my configuration is ok, because I try to create new database at DR site and I can see new instance database in my Backup, Archive and Restore Interface but old instance be cofigured with DataGaurd still can't see in my Backup, Archive and Restore Interface

Thanks,