RAC and SCAN and TNS

Question

Hi
suppose that I have got a RAC (Oracle 11gR2) environment and my SCAN IPs are
172.21.28.115
172.21.28.116
172.21.28.117
I can define TNS name like this
RAC=(DESCRIPTION =
            (ADDRESS=(PROTOCOL=TCP)(HOST=scan)(PORT=1521))
             (CONNECT_DATA=
                (SERVICE=DEDICATED)
                (SERVICE_NAME=rac.com)
)Consider that I don't want use DNS in client side ,_But my RAC servers have a DNS for SCAN_
for example my application server can't use DNS
Now can I substitute the IPs with scan like follow example ?
RAC=(DESCRIPTION =
            (LOAD_BALANCE=YES)
            (ADDRESS=(PROTOCOL=TCP)(HOST=172.21.28.115)(PORT=1521))
             (ADDRESS=(PROTOCOL=TCP)(HOST=172.21.28.116)(PORT=1521))
             (ADDRESS=(PROTOCOL=TCP)(HOST=172.21.28.117)(PORT=1521))
             (CONNECT_DATA=
                (SERVICE=DEDICATED)
                (SERVICE_NAME=rac.com)
)Do I miss any thing if I don't use DNS in Clients?
thanks

Answer 1

Consider that I don't want use DNS in client side ,But my RAC servers have a DNS for SCANyou can still use VIP to make connectivity even you've configured SCAN.
entry would be same as we were using in 10g.
DB =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = tcp)(HOST = ****)(PORT = 1521))
      (ADDRESS = (PROTOCOL = tcp)(HOST = ****)(PORT = 1521))
      (LOAD_BALANCE = yes)
    (CONNECT_DATA =
      (SERVICE_NAME = DB)
      (FAILOVER_MODE =
        (TYPE = select)
        (METHOD = basic)
        (RETRIES = 20)
        (DELAY = 3)
  )