As per what I understood if one of the servers are down then the client will call the next one in the list which would send it a new id after which all calls will be to that one. But in order to decide which server to pick based on the load balancing strategy used I think we may need more information to be passed to the client. Once this discussion is finished i think we should put this in a wiki page as it provides good insights on clustering and the logic used. I can probably do that if no one else wants it :)
Regards Manu On 6/14/07, Paulo Lopes <[EMAIL PROTECTED]> wrote:
The idea of id download on the first connection doesn't seem nice to me. Assume the following scenario: you have a cluster of 3 servers, and the 3 are aware of the other by their internal configuration. (no discovery inside the cluster). The client receives the list of 3 servers and now has to decide which one to connect. It is clear here that the client needs to know some more about the server to decide which one to pick in order to share the load balancing in the cluster, more there is no way for the client to know if one of the servers is down and if it is that server is removed from the list and never connected again during that request. My idea is that perhaps we would better have a small extra server that i will call a service dispatcher, that is the central point for the cluster. no need to change the openejb code each server still works in a isolated way. The SD would have the configurations of where the openejb nodes are in the cluster and their status (up/down). The clients would then connect to the SD and the SD would query the list of servers, and forward to the next available one. Metrics could be gathered from the SD such as time between query and response from OEJB making a simple (not so accurate) load balancer system. Paulo
