Connection Load Balancing and TAF

• client-side connect-time load balancing

Add entry on tnsnames.ora file, here service name is RAC

SOESRV2=
 (DESCRIPTION =
  (ADDRESS_LIST =
    (LOAD_BALANCE=ON)
    (ADDRESS=(PROTOCOL=TCP)(HOST=192.168.56.81)(PORT=1531))
    (ADDRESS=(PROTOCOL=TCP)(HOST=192.168.56.82)(PORT=1531))
   )
  (CONNECT_DATA=(SERVICE_NAME=rac))
 )

C:\app\client\varunyadav\product\12.1.0\client_1\network\admin\sqlnet.ora

Used TNSNAMES adapter to resolve the alias

Attempting to contact (DESCRIPTION = (ADDRESS_LIST = (LOAD_BALANCE=ON) (ADDRESS=(PROTOCOL=TCP)(HOST=192.168.56.81)(PORT=1531)) (ADDRESS=(PROTOCOL=TCP)(HOST=192.168.56.82)(PORT=1531))) (CONNECT_DATA=(SERVICE_NAME=rac)))

OK (20 msec)

C:\Users\varunyadav> sqlplus sys/system123@soesrv2 as sysdba

SQL*Plus: Release 12.1.0.2.0 Production on Wed Jun 5 17:17:34 2019

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

Connected to:

Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production

With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,

Advanced Analytics and Real Application Testing options

SQL> SELECT SYS_CONTEXT('USERENV','SERVICE_NAME') FROM DUAL;

SYS_CONTEXT('USERENV','SERVICE_NAME')

--------------------------------------------------------------------------------

rac

SQL> SELECT INSTANCE_NAME FROM V$INSTANCE;

INSTANCE_NAME

----------------

rac2

By Default Load balancing is done on both server internally, If one database sid is stop due any cause of failure it will automatically move to another server

SQL>

SQL> SELECT INST_ID, COUNT(*)  FROM   GV$SESSION GROUP BY INST_ID ORDER BY INST_ID;

   INST_ID   COUNT(*)

---------- ----------

         1         57

         2         58

SQL>