Hi Christian, Please see http://docs.neo4j.org/chunked/1.4.M06/ha.html for info on Neo4j HA. You can run a coordinator and a Neo4j server on the same machines. That's a common setup. As for how to query it, answering that requires some more explanation about how Neo4j can be run.
Neo4j can be used in two deployment modes: embedded in a Java process, or stand-alone server. The server however internally runs an embedded instance. See http://docs.neo4j.org/chunked/1.4.M06/deployment-scenarios.html for more information on this. In an HA environment, a stand-alone server would be accessed over HTTP via the REST API[1]. You can also write custom extensions[2] in order to deploy Java code on the server so that you can build your own domain-specific query API. If you're not using the stand-alone server, but instead using embedded Neo4j in e.g. a web application deployed on Tomcat, then the API you expose from your webapp is completely up to you. Internally it then uses an embedded Neo4j instance, where you have full access to the Java API. In addition to these options, you can also use our new query language, Cypher[3]. You can try it out from the web administration interface of the stand-alone server. When setting up a Neo4j HA cluster, you typically also configure a load balancer in front of the cluster. The load balancer can use any method it desires to distribute the requests to the machines in the cluster. The load balancer is however not included in the Neo4j distribution -- it is something the user needs to provide. You could look into the Apache HTTP Server or HAProxy. Hope that answers some of your questions. David [1] http://docs.neo4j.org/chunked/1.4.M06/rest-api.html [2] http://docs.neo4j.org/chunked/1.4.M06/server-plugins.html, http://docs.neo4j.org/chunked/1.4.M06/server-unmanaged-extensions.html [3] http://docs.neo4j.org/chunked/1.4.M06/cypher-query-lang.html On Wed, Jul 6, 2011 at 11:22 AM, Christian Godde < christian.go...@googlemail.com> wrote: > Hi there, > > I am quite a newbie with neo4j and I hope somebody can help me. > > I want to set up a Cluster with 6 Servers and a few Coordinators > (can a Server at the same time be a Coordinator?). > Theoretically the setting up of this cluster is more or less clear to me. > But the big question for me is: > How do I query this cluster? > So that I don't communicate with a single server all the time, but the > server with the lowest load at this time. > > I hope you know what I mean. > > Regards, > Christian > _______________________________________________ > Neo4j mailing list > User@lists.neo4j.org > https://lists.neo4j.org/mailman/listinfo/user > -- David Montag <david.mon...@neotechnology.com> Neo Technology, www.neotechnology.com Cell: 650.556.4411 Skype: ddmontag _______________________________________________ Neo4j mailing list User@lists.neo4j.org https://lists.neo4j.org/mailman/listinfo/user