Hi,

When I try to connect to the db directly..

$sqlplus username/password

it gives me......
ERROR:
ORA-01034: ORACLE not available
ORA-27121: unable to determine size of shared memory segment
SVR4 Error: 13: Permission denied

But when I give
$sqlplus username@oracle_sid/password

Its getting connected.

My oracle_sid has been set in by the env varibale.

$echo $ORACLE_SID
sid
$

Can anyone please tell me where the problem might be?