there is no more network discovery with smb2 or smb3
Windows Systems are using WS-Discovery (WSD) instead which is not part of samba this time, so windows systems are still able to discover other windows systems in the network Neighbourhood but no samba servers
freenas/truenas has an implementation that works also for samba, but i did not test if this is usable on UCS too as i don’t need the network browsing for shares (they are all mapped through GPO)
here is a good description for that:
rg
Christian