Answer by Jacek J. ·
Each NAM server requires separate database. No exceptions from that rule, this statement is correct for standalone NAM servers, elements of load balancing clusters and elements of failover clusters as well.
However, it is possible to run more than one database on single SQL server, which means multiple (all?) your reporting servers my work with single SQL server. All you need to remember in such configuration is to assure sufficient resources for SQL server, to avoid performance issues.