Hi @guolulu: I hope you are setting up multiple app layer application servers for high availability and to maintain the load for the same application. The installation should be done one time (via IUA or command line script). The installation will help to load the data base with the required data. Post that the app server configuration should be done in the required number of servers pointing to the same database.
Hi @guolulu: In a high level, this is correct. When you say install pega in one server, I hope you are referring to the DB server. It is better to do the installation (install.sh) from a server which is close with the DB server because the installation will load the objects to DB (preferably DB server).
Please see installation guide to get more details on the configurations.
Please also look into the latest architecture change from PEGA where your application work load should be deployed as containers in kubernetes.