RAC Attack - Oracle Cluster Database at Home/RAC Attack 12c/Configure Oracle Client


In order to test failover it would be best to connect from a client outside the cluster, so we'll start by downloading and installing Oracle's Basic Instant Client (English-only) and the Instant Client SQLPlus package. Then we'll configure the DNS resolution and the local TNS naming to use the SCAN addresses.



  1. Download Oracle's Basic (English-only) Instant Client and Oracle's Instant Client SQLPlus package from Oracle's website here:
  2. http://www.oracle.com/technetwork/topics/winx64soft-089540.html


    The two files you need are:

  • instantclient-basiclite-windows.x64-12.1.0.1.0.zip
  • instantclient-sqlplus-windows.x64-12.1.0.1.0.zip
  • Each archive contains a folder named "instantclient_12_1". Extract this folder (from both archives) into C:\. (In Explorer you can drag-and-drop or you can choose "Extract All" from the File menu.)
  • Open the Windows Network Settings (Control Panel -> Network and Internet -> Network and Sharing Center.
  • Click on VirtualBox Host-Only Network RA-Windows_7-Network Settings
  • Click on Properties
  • RA-Windows_7-Network Status
  • Select Internet Protocol Version 4 (TCP/IPv4) and click Properties.
  • RA-Windows_7-Network Properties
  • Select Use the following DNS server addresses: and enter the addresses of the two virtual machines:
    • Preferred DNS server: 192.178.78.51
    • Alternate DNS server: 192.178.78.52
    Click on Advanced... RA-Windows_7-Network IPV4 Properties
  • Select the DNS tab. Select Append these DNS suffixes (in order):, click Add... and enter racattack in the Domain suffix field that appears. Click Add.
  • Check both Register the connection's addresses in DNS and Use this connection's DNS suffix in DNS registration. Click OK and/or Close until you exit from the Network configuration. RA-Windows_7-Network IPV4 Advanced Properties
  • Open a Command prompt and check that the DNS resolution is working properly on your laptop:
  • C:\Users\luc> nslookup - 192.168.78.51 Default Server: collabn1.racattack Address: 192.168.78.51 > collabn-cluster-scan Server: collabn1.racattack Address: 192.168.78.51 Name: collabn-cluster-scan.racattack Addresses: 192.168.78.252 192.168.78.253 192.168.78.251 > ^C C:\Users\luc> RA-Windows_7-Nslookup Scan
  • Test your Instant Client installation by connecting to the database.
  • C:\instantclient_12_1> sqlplus system/racattack@//collabn-cluster-scan/RAC.racattack SQL*Plus: Release 12.1.0.1.0 Production on Wed Aug 14 13:34:24 2013 Copyright (c) 1982, 2013, Oracle. All rights reserved. Connected to: Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP, Advanced Analytics and Real Application Testing options SQL> select instance_name from v$instance; INSTANCE_NAME ---------------- RAC1 SQL>
  • Let's open and test our Pluggable Database PDB (it isn't opened by default).
  • SQL> connect sys/racattack@//collabn-cluster-scan/RAC.racattack as sysdba Connected. SQL> alter pluggable database PDB open; Pluggable database altered. SQL> connect system/racattack@//collabn-cluster-scan/PDB.racattack Connected. SQL> show con_name CON_NAME ------------------------------ PDB SQL>
  • Create a TNSNAMES files and copy the RAC entry from either cluster database node. Also create a similar entry for the PDB service.
  • C:\instantclient_12_1> notepad C:\instantclient_12_1\tnsnames.ora RAC = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = collabn-cluster-scan.racattack)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = RAC.racattack) ) ) PDB = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = collabn-cluster-scan.racattack)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = PDB.racattack) ) )
  • Test your TNSNAMES by setting the TNS_ADMIN environment variable and running SQLPLUS.
  • C:\instantclient_12_1> set TNS_ADMIN=c:\instantclient_12_1 C:\instantclient_12_1> sqlplus system/racattack@RAC SQL*Plus: Release 12.1.0.1.0 Production on Wed Aug 14 14:21:24 2013 Copyright (c) 1982, 2013, Oracle. All rights reserved. Last Successful login time: Wed Aug 14 2013 14:20:59 +02:00 Connected to: Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP, Advanced Analytics and Real Application Testing options SQL> connect system/racattack@PDB Connected. SQL>