an OPS question - tnsnames

Dear list !
I've got an OPS database named OPS with 2 instances OPS1 and OPS2 . I want the clients to connect to the instance OPS1 and , if OPS1 becomes unavailable , to connect to OPS2 .
The Oracle version is 8.0.5
I put the following lines in clients' tnsnames.ora file :

OPS.world = (DESCRIPTION_LIST =

        (DESCRIPTION = 


          (ADDRESS = (PROTOCOL = tcp) (HOST = DB1) (PORT = 1526))

          (CONNECT_DATA = (SID = OPS1))

        )
        (DESCRIPTION = 


          (ADDRESS = (PROTOCOL = tcp) (HOST = DB2) (PORT = 1526))

          (CONNECT_DATA = (SID = OPS2))

        )

The problem is that when both the instances are up and running , it looks like clients connect to one of the instances randomly . How can i ensure that they will try to connect to OPS1 first , and only if it is unavailable , they'll connect to OPS2.

Thanks a lot in advance .

DBAndrey
 mailto:andreyb_at_elrontelesoft.com

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Author: Andrey Bronfin
  INET: andreyb_at_elrontelesoft.com

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