You need to read the technology section on our web site that explains Aware IM architecture. Once you understand the architecture the following will make sense to you:
1) The default configuration does not support clustering and fail-over and, therefore, failure of any component (web server, Aware IM server or the database) will be fatal for the entire system
2) You can cluster all 3 above mentioned components, so that you have several web servers, several Aware IM servers and database with mirroring/replication. Depending on how you do this, failure of one component will not be fatal. For example, if you cluster several web servers, but only have one Aware IM server, then some web servers may become redundant, but the Aware IM server will become "a single-point-of-failure".
If, however, you cluster both web servers, Aware IM servers and use mirroring/replication for the database, then there will be no single points of failure in the system and every component may become redundant.
