Does anyone know the "acquisition" in the quote below is referring to Major Acquisition, Minor Acquisition, or both?
"When Ping Sweep is enabled, the UTPing program in $NMSROOT/campus/bin will be invoked during acquisition to send out a sweep of pings for each subnet."
It appears hosts that have short-lived or no IP ARP entries on the routers/layer-3 switches do not get picked up by UT.
Dynamic UT relies on the MAC address notification traps from the CISCO-MAC-ADDRESS-NOTIFICATION-MIB. That is really the key. You can still get MAC updates (provided you're sending traps to the CiscoWorks server) even without UTLite or DHCP snooping.