Clustering and user lists

When you create multiple instances of WebSphere® application servers running ZIETrans applications and sharing the same application files, you can use user lists on multiple-logon hosts without any special considerations. However, there are special considerations for the use of user lists with single-logon hosts:

• In vertical clustering, where application-related files are not physically copied to each application server but are merely represented in memory, you cannot use user lists. This restriction exists because every application server running ZIETrans would need a user list for its exclusive use; but in fact there is only one user list.
• In horizontal clustering, where multiple copies of an application are running in separate application servers, you must modify the user list in each copy of the application to ensure that no two copies have a user ID in common.