Re: Load balancing between an RAC database cluster and Top Link

"Greg Collett" <gcollett_at_reserveamerica.com> wrote in message news:1f7e9d73.0401260604.19ad4d64_at_posting.google.com...
> All,
>
> We are designing an environment which is comprised of 3 database
> servers clustered together using RAC 10g. Connecting to the database
> is an Oracle Application Cluster of 4 App Servers running toplink.
> Currently the connection is facilitated through XML using oracle jdbc
> drivers.
>
> My question: In order to properly load balance the calls to the
> databse servers, do I require a hardware level load balancer between
> the Application tier and the Database tier?
>
> My understanding is that Oracle chares the db cache between the 3
> servers, and I believe it does load balancing between the servers as
> well. However, the jdbc connection on the app servers currently points
> at 1 database machine directly, and if that machine went down, the app
> could not connect to the RAC cluster (without a manual change). Is
> there a non-hardware solution to get around this?

Greg,

yes in Oracle 9.2 (no 10g documentation available yet) you can configure Oracle Net Services on your App Servers to provide connection load balancing across the nodes of your cluster (see
http://download-west.oracle.com/docs/cd/B10501_01/network.920/a96580/advcfg. htm#475650 ). If you are worried about a cluster node going down you could also look at the Transparent Application Failover options, which provide varying degrees of application resilience.

regards

Paul Dixon Received on Mon Jan 26 2004 - 10:05:26 CST