RAC and db connections

From: <wagen123_at_yahoo.com>
Date: Thu, 23 Aug 2007 07:29:24 -0700
Message-ID: <1187879364.092128.136030@z24g2000prh.googlegroups.com>

Oracle10g 10.2.0.3 (64 bit)
RHEL 4.3 (64 bit)
4 node RAC cluster

Often we see all db connections from the application/client go to one node ONLY, even though the ALL nodes are relatively idle. Even if we make an explicit connection to an instance on a specific node it gets redirected to another node (local listener is setup).

How do I determine why the connections are being routed to the other nodes? What is causing this and how to fix it?

ex. of the connection string from the client TEST =
  (DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = node1v)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = node2v)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = node3v)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = node4v)(PORT = 1521))
(LOAD_BALANCE = yes)
(FAILOVER = ON)
(CONNECT_DATA =

      (SERVER = DEDICATED)
      (SERVICE_NAME = SRVR)
      (FAILOVER_MODE =
        (TYPE = SELECT)
        (METHOD = BASIC)
        (RETRIES = 180)
        (DELAY = 5)
      )

    )
  )

Thanks for any pointers.
wagen Received on Thu Aug 23 2007 - 09:29:24 CDT