A solid understanding of the Search History utility in the VCS interface is vital to the effective troubleshooting of failed calls. To access the Search History, go to Status > Search History. This presents a list of up to the last 255 searches performed by the VCS, both successful and failed. Clicking on the “view” link will show the search details of the attempt, which contain a wealth of information. Among the details, you’ll find the zones and subzones searched, Transforms, Search Rules and results, Admin Policies and User Policies, and call policies. Additional information can be found on the Event Log and Call Summary links.
I’ve found it extremely helpful to give a detailed read of the Search History Details on both successful and unsuccessful calls in order to fully understand the incremental steps taken by the VCS in the process of connecting a call. When attempting to connect a call, a VCS will execute its search process in exactly the same way every time: It will first apply any Transforms, in order of priority, and see if any of its registered endpoints match the search. If not, it then applies Admin policies, then User (Find Me) Policies, and finally each of the Search Rules. If you are already familiar with the policies and search rules configured on the VCS, you can see them being applied step by step through the search process. In the process of watching each step of the successful searches, one can learn to quickly analyze the failed searches and possible corrective actions.
For more information, you can refer to the VCS Admin Guide, in the Dial Plan and Call Processing section.