Setting up application tiers with Stand by dataguard on oracle e-biz r12.

Cheers everyone,

I am having the following issue.

The database is already setup with standby successfully, but the application tiers, i am still struggling with it. 

 I am having the following issue on the standby tier.

I am getting the following error on the standby server when trying to connect via sqlplus on teh appstier>

ERROR:
ORA-12505: TNS:listener does not currently know of SID given in connect
descriptor
Here is some info:

settings on the primary:

-bash-3.00$ echo $ORACLE_SID

-bash-3.00$ echo $TWO_TASK
orcl

dbport here is 1527

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setting on the standby:

-bash-3.00$ echo $ORACLE_SID

-bash-3.00$ echo $TWO_TASK