Maybe checking which IPs are using port 5480? It is used by vCenter Appliance Management Console (VAMI, only for VCSA, not windows). vRealize Network Insight may help you with that, but you have plenty of options to scan the network and check that.
- nc -zvw10 *IP* 5480
z: zero-I/O mode which is used for scanning
v: for verbose output
w10: timeout wait seconds
- nmap *IP* -p 5480
- telnet *IP* 5480