The format of the seed file for Cisco ACI fabric discovery must be:
<Cisco ACI ControllerNode IP/Hostname> SNMPSTATE=TM_NONSNMP SOURCETYPE=TM_REST ACCESSMODE=ICMPONLY
Example
10.106.124.155 SNMPSTATE=TM_NONSNMP SOURCETYPE=TM_REST ACCESSMODE=ICMPONLY
Refer VMware Smart Assurance IP Manager User Guide for further details about discovery using seed file.