When Nmap is installed on a MID Server, the installer configures the Nmap capability for that MID Server. Horizontal, Discovery requires this capability for any MID Server used for credential-less Discovery and will not initiate an Nmap scan using a non-compliant MID Server. Service Mapping, however, does not check for the presence of the Nmap capability and selects the MID Server based on the IP address only. It is therefore possible for Service Mapping to select a MID Server that does not have Nmap installed. This condition logs the following error:

Nmap is not installed on MID Server. Verify all MIDs configured to handle selected IP Address have Nmap Capability.

To ensure that Service Mapping does not select a MID Server without the Nmap capability, install Nmap on all MID Servers assigned to the IP address ranges on which you want credential-less Discovery to be available.