Вопрос: Почему ошибка ORA-12514: TNS:listener does not currently know of service requested in connect descriptor?

Лучший ответ:
Вот тут пишут, что надо исправить SERVICE_NAME в tnsnames.ora

Худший ответ:
В общем в одной подсети инстансы oracle с одинаковыми service name и портами жить могут.
в listener.ora добавляем информацию о новом подключении по IP и меняем портLISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 2001))
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC2001))
    )
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.22)(PORT = 2001))
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC2001))
    )	
  )
В tnsnames.ora заносим информацию о новых экземплярахSERVER01_DBORACLE_LOCAL =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.22)(PORT = 2001))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = dboracle)
    )
  )  
  
SERVER01_DBORACLE =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 2001))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = dboracle)
    )
  )    
ORACLR_CONNECTION_DATA =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC2001))
    )
    (CONNECT_DATA =
      (SID = CLRExtProc)
      (PRESENTATION = RO)
    )
  )

LISTENER_DBORACLE =
  (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 2001))
После перезапускаем службы листенера и самой БД.
Проверяем командой 
lsnrctl statusLSNRCTL for 64-bit Windows: Version 12.2.0.1.0 - Production on 13-APR-2017 16:27:57

Copyright (c) 1991, 2016, Oracle.  All rights reserved.

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=2001)))
STATUS of the LISTENER
------------------------
Alias                     LISTENER
Version                   TNSLSNR for 64-bit Windows: Version 12.2.0.1.0 - Production
Start Date                13-APR-2017 15:28:54
Uptime                    0 days 0 hr. 59 min. 2 sec
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF
Listener Parameter File   D:\DataBases\Oracle\product\12.2.0\dbhome_1\network\admin\listener.ora
Listener Log File         D:\DataBases\Oracle\diag\tnslsnr\SERVER01\listener\alert\log.xml
Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=127.0.0.1)(PORT=2001)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(PIPENAME=\\.\pipe\EXTPROC2001ipc)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.0.22)(PORT=2001)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(PIPENAME=\\.\pipe\EXTPROC2001ipc)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcps)(HOST=SERVER01)(PORT=5500))(Security=(my_wallet_directory=D:\DATABASES\ORACLE\admin\dboracle\xdb_wallet))(Presentation=HTTP)(Session=RAW))
Services Summary...
Service "CLRExtProc" has 1 instance(s).
  Instance "CLRExtProc", status UNKNOWN, has 1 handler(s) for this service...
Service "dboracle" has 1 instance(s).
  Instance "dboracle", status READY, has 1 handler(s) for this service...
Service "dboracleXDB" has 1 instance(s).
  Instance "dboracle", status READY, has 1 handler(s) for this service...
The command completed successfully
обязательно должна быть информация о Service "dboracle" has 1 instance(s).
  Instance "dboracle", status READY, has 1 handler(s) for this service...
Service "dboracleXDB" has 1 instance(s).
  Instance "dboracle", status READY, has 1 handler(s) for this service...
lsnrctl reload – переинициализировать листенер иногда помагает, когда инстанс не инициализовался листенером