Oracle Error ORA-02708: osnrntab: connect to host failed, unknown ORACLE_SID

Oracle Error Message

ORA-02708: osnrntab: connect to host failed, unknown ORACLE_SID

Reason for the Error

The invoked Unix two-task driver failed to find an entry in oratab for the sid you supplied.

Solution

First, check whether you have read access to oratab, and see if the desired sid is there. Add an entry to oratab for the desired sid, if necessary.