CMDB Reconciliation
In a post titled "Reconciliation: The Key to an Accurate CMDB" the author suggest that discovery and mapping tools are key to ensure the accuracy of a CMDB. However, this solves only one of the problems: how to ensure that the infrastructure state matches what is in the CMDB. The issue is that there is no way to know if what is discovered ought to be or is simply the result of out of band management.
The key to solve this issue is to drive the configuration and changes through the CMDB, by integrating the CMDB with change management, release management or configuration tools.