We are planning to perform an upgrade of our existing Pega Platform 6.3 SP1 to 8.3. Our system is using IBM Websphere and IBM DB2. We noted that there is an upgrade guide for Pega 8.3 published in the knowledgebase.
We would suggest you to take care of -Dnodetype and -DapplicableNodeType. Plus do check search related stuff properly.
There has been some changes done to node classification from Pega 8.2. Basically if you choose to define DapplicableNodeTypes , and don’t define -DapplicableNodeTypes as WebUser,Stream,Search,BackgroundProcessing (these four are must now) nodes won’t come up.