In addition to server side-load balancing you have two options: - CPU runqueue-based load balancing - or round-robin balancing in order to configure this you should set in your listener.ora the parameter prefer_least_loaded_node_<listerer name>=off For applications that connect at startup time only and not frequently reconnecting, switch this parameter off will give you an 'almost' :-) even connection distribution across all nodes. regards, goran On Nov 17, 2007 2:20 PM, Andreas Piesk <a.piesk@xxxxxxx> wrote: > William Wagman schrieb: > > > > And the mirror image on node 2. This is puzzling to me as the > > tnsnames.ora listed in example 9.1 of the Real Application Clusters > > Installation guide looks like the one I currently have. I think my lack > > of understanding has to do with how the local and remote listener > > parameters function so if someone could help me in my understanding I > > would be most grateful. > > you're right, LOCAL_LISTENER on each node should point to the listener > on that node. REMOTE_LISTENER should point to all listeners on all nodes > if you want server side load balancing, otherwise don't set > REMOTE_LISTENER. > > so to make your configuration right, you should setup it like this: > > node1: > > LOCAL_LISTENER_NODE1 = > (ADDRESS_LIST = > (ADDRESS = > (PROTOCOL = TCP) > (HOST = node1-vip) > (PORT = 1521) > ) > ) > REMOTE_LISTENERS = > (ADDRESS_LIST = > (ADDRESS = > (PROTOCOL = TCP) > (HOST = node1-vip) > (PORT = 1521) > ) > (ADDRESS = > (PROTOCOL = TCP) > (HOST = node2-vip) > (PORT = 1521) > ) > ) > > LOCAL_LISTENER=LOCAL_LISTENER_NODE1 > REMOTE_LISTENER=REMOTE_LISTENERS > > > node2: > > LOCAL_LISTENER_NODE2 = > (ADDRESS_LIST = > (ADDRESS = > (PROTOCOL = TCP) > (HOST = node2-vip) > (PORT = 1521) > ) > ) > REMOTE_LISTENERS = > (ADDRESS_LIST = > (ADDRESS = > (PROTOCOL = TCP) > (HOST = node1-vip) > (PORT = 1521) > ) > (ADDRESS = > (PROTOCOL = TCP) > (HOST = node2-vip) > (PORT = 1521) > ) > ) > > LOCAL_LISTENER=LOCAL_LISTENER_NODE2 > REMOTE_LISTENER=REMOTE_LISTENERS > > > on a 2-node cluster your REMOTE_LISTENER can point to a single listener > but i find it easier to keep REMOTE_LISTENER identical on all nodes. > > the purpose of REMOTE_LISTENER is to connect all instances with all > listeners so the instances can propagate their load balance advisories > to all listeners. if you connect to a listener, this listener uses the > advisories to decide who should service your connect. if the listener > decides its local instance(s) are least loaded and should service your > connect it passes your connect to the local instance. if the node you > connected to is overloaded, the listener can use TNS redirect to > redirect your connect a less loaded instance. > > > regards, > -ap > -- > //www.freelists.org/webpage/oracle-l > > >