SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = PLSExtProc)
      (ORACLE_HOME = /u01/oracle)
      (PROGRAM = extproc)
    )
   (SID_DESC =

    (GLOBAL_DBNAME =lsnode2)

    (ORACLE_HOME = /u01/oracle)

    (SID_NAME = dgdemo)


   )

  )

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = node2)(PORT = 1521))
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC0))
    )

  )

LSNODE2 =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.189)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = dgdemo)
    )
  )

LSNODE1 =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.188)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = dgdemo)
    )
  )

EXTPROC_CONNECTION_DATA =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC0))
    )
    (CONNECT_DATA =
      (SID = PLSExtProc)
      (PRESENTATION = RO)
    )
  )

[oracle@node2 admin]$ sqlplus system/oracle@lsnode1

SQL*Plus: Release 10.2.0.1.0 - Production on Wed Mar 3 11:30:32 2010

Copyright (c) 1982, 2005, Oracle.  All rights reserved.

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


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