connect internal and dataguard via ora_session_mode => ORA_SYSDBA

So I am trying to use the ora_session_mode => ORA_SYSDBA attr with
the DBD::Oracle and cannot not get it to work.

I want to connect to the standby and the primary: xxx_a and xxx_b. But
I cannot connect to the standby unless I connect as sysdba -
naturally.

I can connect via sqlplus to both using as sysdba.

I have read you need to set the ENV ORACLE_SID, but that does not work
either. So perhaps it is not possible?

thanks
dn

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