[oracle@trac1 trace]$ srvctl config database -db ora12c2
Database unique name: ORA12C2
Database name: ORA12C2
Oracle home: /u/app/oracle/product/12.2/db
Oracle user: oracle
Spfile: +DATA/ORA12C2/PARAMETERFILE/spfile.268.1033293017
Password file: +DATA/ORA12C2/PASSWORD/pwdora12c2.256.1033292739
Domain:
Start options: open
Stop options: immediate
Database role: PRIMARY
Management policy: AUTOMATIC
Server pools:
Disk Groups: FRA,DATA
Mount point paths:
Services:
Type: RAC
Start concurrency:
Stop concurrency:
OSDBA group: dba
OSOPER group: oper
Database instances: ORA12C21,ORA12C22
Configured nodes: trac2,trac1
CSS critical: no
CPU count: 0
Memory target: 0
Maximum memory: 0
Default network number for database services:
Database is administrator managed
[oracle@trac1 trace]$ srvctl config service -db ora12c2
[oracle@trac1 trace]$

SQL> show parameter listen

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
listener_networks                    string
local_listener                       string       (ADDRESS=(PROTOCOL=TCP)(HOST=     10.36.21.15)(PORT=1521))
remote_listener                      string       trac-scan:1521

SQL> show parameter service_name

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
service_names                        string      ORA12C2

[oracle@trac1 trace]$ lsnrctl services

LSNRCTL for Linux: Version 12.2.0.1.0 - Production on 02-MAR-2020 07:55:52

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

Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
Services Summary...
Service "+ASM" has 1 instance(s).
  Instance "+ASM2", status READY, has 1 handler(s) for this service...
    Handler(s):
      "DEDICATED" established:0 refused:0 state:ready
         LOCAL SERVER
Service "+ASM_DATA" has 1 instance(s).
  Instance "+ASM2", status READY, has 1 handler(s) for this service...
    Handler(s):
      "DEDICATED" established:0 refused:0 state:ready
         LOCAL SERVER
Service "+ASM_FRA" has 1 instance(s).
  Instance "+ASM2", status READY, has 1 handler(s) for this service...
    Handler(s):
      "DEDICATED" established:0 refused:0 state:ready
         LOCAL SERVER
Service "+ASM_OCR_VOTING" has 1 instance(s).
  Instance "+ASM2", status READY, has 1 handler(s) for this service...
    Handler(s):
      "DEDICATED" established:0 refused:0 state:ready
         LOCAL SERVER
Service "ORA12C2" has 1 instance(s).
  Instance "ORA12C22", status READY, has 1 handler(s) for this service...
    Handler(s):
      "DEDICATED" established:2 refused:0 state:ready
         LOCAL SERVER
Service "ORA12C2XDB" has 1 instance(s).
  Instance "ORA12C22", status READY, has 1 handler(s) for this service...
    Handler(s):
      "D000" established:0 refused:0 current:0 max:1022 state:ready
         DISPATCHER <machine: trac1, pid: 20321>
         (ADDRESS=(PROTOCOL=tcp)(HOST=trac1)(PORT=15695))
The command completed successfully

[oracle@trac1 ~]$ srvctl config scan_listener
SCAN Listener LISTENER_SCAN1 exists. Port: TCP:1521
Registration invited nodes:
Registration invited subnets:
SCAN Listener is enabled.
SCAN Listener is individually enabled on nodes:
SCAN Listener is individually disabled on nodes:
SCAN Listener LISTENER_SCAN2 exists. Port: TCP:1521
Registration invited nodes:
Registration invited subnets:
SCAN Listener is enabled.
SCAN Listener is individually enabled on nodes:
SCAN Listener is individually disabled on nodes:
SCAN Listener LISTENER_SCAN3 exists. Port: TCP:1521
Registration invited nodes:
Registration invited subnets:
SCAN Listener is enabled.
SCAN Listener is individually enabled on nodes:
SCAN Listener is individually disabled on nodes:

trac =
 (DESCRIPTION =
  (CONNECT_TIMEOUT=90) (RETRY_COUNT=20)(RETRY_DELAY=3) (TRANSPORT_CONNECT_TIMEOUT=3)
  (ADDRESS = (PROTOCOL = TCP)(HOST=trac-scan.orient.root.biz)(PORT=1521))
  (CONNECT_DATA=(SERVICE_NAME=ORA12C2)))

TEST  @ trac> select * from tab;

                  X Y
------------------- ----------------------------------------------------------
                  1 before shut

Elapsed: 00:00:00.43

--- гасим инстанс где залогонен.

TEST  @ trac> select * from tab;
select * from tab
*
ERROR at line 1:
ORA-03113: end-of-file on communication channel
Process ID: 19617
Session ID: 52 Serial number: 36108


ERROR:
ORA-03114: not connected to ORACLE


Elapsed: 00:00:00.02
TEST  @ trac> select * from tab;
ERROR:
ORA-03114: not connected to ORACLE

TEST  @ trac> exit
Disconnected from Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production

C:\Windows\system32>sqlplus test/test@trac

SQL*Plus: Release 12.1.0.2.0 Production on Fri Feb 28 16:23:02 2020

Copyright (c) 1982, 2014, Oracle.  All rights reserved.

Last Successful login time: Fri Feb 28 2020 16:02:58 +10:00

Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production


Session altered.

Elapsed: 00:00:00.28

Session altered.

Elapsed: 00:00:00.27
TEST  @ trac> select * from tab;

                  X Y
------------------- -------------------------------------------------------------------------------
                  1 before shut

MYRAC_TAF =
 (DESCRIPTION = 
   (ADDRESS = (PROTOCOL = TCP)(HOST = xxxxx)(PORT = 1521)) 
 (CONNECT_DATA =
   (SERVER = DEDICATED)
   (SERVICE_NAME = myrac)
     (FAILOVER_MODE=
       (TYPE=select)
       (METHOD=basic))))