ORA-12514: TNS:listener does not currently know of service requested in connect

If your environment is windows, the file corresponding to the service of OracleOraDb10g_home1TNSListener is located the file of %Oracle_Hoem\bin\TNSLSNR.EXE

If the services is not started，the error comes: Ora-12514：TNS：无监听程序。

on the other hand,if the service of OracleServiceORACLE is not started,the error comes: Ora-12514：TNS：监听程序当前无法识别链接描述符 中请求的服务。

But ,if the two services are started, Maybe the error also comes ORA-12514 , you need modify the listener.ora file.

On linux environment and  windows environment, you need modify the listener.ora file.

I modify the listener.ora file on linux environment below. the listener.ora file content on linux environment is the same as on the windows environment.

Last login: Sun Jan  8 19:53:40 2012 from 192.168.11.1
[root@TrainingServer ~]# su - oracle
[oracle@TrainingServer ~]$ sqlplus /nolog

SQL*Plus: Release 10.2.0.5.0 - Production on Sun Jan 8 20:09:11 2012

Copyright (c) 1982, 2010, Oracle.  All Rights Reserved.

SQL>

SQL> conn /as sysdba
Connected.
SQL> disc

SQL> conn system/oracle@king as sysdba
ERROR:
ORA-12514: TNS:listener does not currently know of service requested in connect
descriptor
SQL> exit

[oracle@TrainingServer ~]$ cd $ORACLE_HOME/network/admin
[oracle@TrainingServer admin]$ ls
listener1201087PM5729.bak  listener.ora  shrept.lst                 tnsnames1201087PM5931.bak
listener1201087PM5931.bak  samples       tnsnames1201087PM5729.bak  tnsnames.ora
[oracle@TrainingServer admin]$ ls -l
total 32
-rw-r--r-- 1 oracle oinstall  510 Jan  8 19:59 listener.ora
drwxr-x--- 2 oracle oinstall 4096 Jan  8 18:39 samples
-rw-r--r-- 1 oracle oinstall  172 Dec 26  2003 shrept.lst
-rw-r--r-- 1 oracle oinstall  531 Jan  8 19:58 tnsnames.ora
[oracle@TrainingServer admin]$ vi listener.ora

# listener.ora Network Configuration File: /u01/app/oracle/product/10.2.0/db_1/network/admin/listener.ora
# Generated by Oracle configuration tools.

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = PL***tProc)
      (ORACLE_HOME = /u01/app/oracle/product/10.2.0/db_1)
      (PROGRAM = extproc)
    )
  )

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = TrainingServer)(PORT = 1521))
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC0))
    )
  )


[oracle@TrainingServer admin]$ vi listener.ora

# listener.ora Network Configuration File: /u01/app/oracle/product/10.2.0/db_1/network/admin/listener.ora
# Generated by Oracle configuration tools.

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = PL***tProc)
      (ORACLE_HOME = /u01/app/oracle/product/10.2.0/db_1)
      (PROGRAM = extproc)
    )
    (SID_DESC =
      (GLOAB_NAME = king)
      (ORACLE_HOME = /u01/app/oracle/product/10.2.0/db_1)
      (SID_NAME = king)
    )
  )

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = TrainingServer)(PORT = 1521))
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC0))
    )
  )


[oracle@TrainingServer admin]$ lsnrctl stop

LSNRCTL for Linux: Version 10.2.0.5.0 - Production on 08-JAN-2012 20:05:10

Copyright (c) 1991, 2010, Oracle.  All rights reserved.

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=TrainingServer)(PORT=1521)))
The command completed successfully
[oracle@TrainingServer admin]$ lsnrctl start

LSNRCTL for Linux: Version 10.2.0.5.0 - Production on 08-JAN-2012 20:05:16

Copyright (c) 1991, 2010, Oracle.  All rights reserved.

Starting /u01/app/oracle/product/10.2.0/db_1/bin/tnslsnr: please wait...

TNSLSNR for Linux: Version 10.2.0.5.0 - Production
System parameter file is /u01/app/oracle/product/10.2.0/db_1/network/admin/listener.ora
Log messages written to /u01/app/oracle/product/10.2.0/db_1/network/log/listener.log
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=TrainingServer)(PORT=1521)))
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC0)))

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=TrainingServer)(PORT=1521)))
STATUS of the LISTENER
------------------------
Alias                     LISTENER
Version                   TNSLSNR for Linux: Version 10.2.0.5.0 - Production
Start Date                08-JAN-2012 20:05:16
Uptime                    0 days 0 hr. 0 min. 0 sec
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF
Listener Parameter File   /u01/app/oracle/product/10.2.0/db_1/network/admin/listener.ora
Listener Log File         /u01/app/oracle/product/10.2.0/db_1/network/log/listener.log
Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=TrainingServer)(PORT=1521)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC0)))
Services Summary...
Service "PL***tProc" has 1 instance(s).
  Instance "PL***tProc", status UNKNOWN, has 1 handler(s) for this service...
Service "king" has 1 instance(s).
  Instance "king", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
[oracle@TrainingServer admin]$ sqlplus /nolog

SQL*Plus: Release 10.2.0.5.0 - Production on Sun Jan 8 20:05:20 2012

Copyright (c) 1982, 2010, Oracle.  All Rights Reserved.

SQL> conn system/oracle@king
Connected.
SQL>

--The End!