We are going to set up a reliable J2EE application server environment by using clustering webgoic servers on TWO nodes, and a front OHS https server in DMZ for load balancing.
I am new to weblogic cluster and load balance by OHS. I have visited this forum for Fusion MiddleWare clustering etc. Can some experts share some light on this?
Will our deployment architecture be able to handle the J2EE applications failover? In other word, we can restart one of Weblogic Managed Servers when a new release of J2EE codes are re-deployed without impacting business end users’s usage?
Problems we want to solve:
1. All J2EE applications are available for 24x7 even when new J2EE codes are released and deployed on weblogic Managed Servers ANY TIME, side-by-side deployment and restart a managed server if we need to clean the HTTP cache.
2. The J2EE applications should be accessed by external and internal users with a Single Access Point, like
All J2EE applications (j2ee1, j2ee2, j2ee3 etc) should be deployed on both of weblogic Servers in a cluster, and pointing to a SAME backend database.
Can some experts share with us the best practices on components and configurations? Thanks.
Seems your architecture is like Browser => OHS ( DMZ ) => Weblogic => DB OR Browser => HLB( like bigip ) => OHS ( DMZ ) => Weblogic => DB
Cluster is the solution for load balancing however if you are using OHS for redirection to weblogic then OHS does the load balancing in round robin way. using cluster in this way has a benefit of in case of any one of your managed server is down the OHS will divert connection request to any one of the active managed server ( you have to turn on dynamic list on at OHS ).
Failover is something different, if in case any of the any managed server goes down then your user you get the application session from another server but new one, means the the tasks not saved by the users on earlier session will lost. for that yo need to use cluster and then need to enable the session replication. another best option is you can use the coherence web if you are using latest versions of weblogic supporting coherence web. with that you not need to worry on user sessions and you can start any of the managed server anytime without worrying about the user sessions.
another way is, you can use side by side deployment feature in case you don't want shutdown your application completely, with this, old connections and new requests will goes to old application and once new application activated all new requests will come to new application and once all requests on old application will complete that application will retire automatically.