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When I try to connect to Oracle 11g using:

sqlplus noah/noah@orcl

I get these errors:

ORA-01034: ORACLE not available
ORA-27101: shared memory realm does not exist
Linux Error: 2: No such file or directory
Process ID: 0
Session ID: 0 Serial number: 0

The service does start up when I connect as sysdba using:

sqlplus /nolog
conn / as sysdba

Here's my listener.ora:

  (GLOBAL_DBNAME = orcl)
  (ORACLE_HOME = /opt/oracle/112)
  (SID_NAME = orcl)

  (ADDRESS = (PROTOCOL = TCP)(HOST = mylinux)(PORT = 1521))

And the tnsnames.ora:

(ADDRESS = (PROTOCOL = TCP)(HOST = mylinux)(PORT = 1521))
  (SERVICE_NAME = orcl)

Here is the sqlnet.ora:


Could anyone give me a hand making this work?

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migrated from Dec 22 '11 at 14:06

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Did you start the listener? When you conn / as sysdba, you don't use it, but as soon as you specify a TNS entry like @orcl, you will – fge Dec 21 '11 at 15:51
I've started it! – Shuo Dec 22 '11 at 3:04
And what does lsnrctl status say? Do you see your orcl service? – fge Dec 22 '11 at 8:10
Yes,the orcl service has started! – Shuo Dec 26 '11 at 13:49
Are you sure the startup completes successfully? What is the status of your instance (eg: do a SELECT status, instance_name FROM v$instance; as a user with DBA privileges) – NullUserException Dec 28 '11 at 0:31

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