if my fas2020 is using all "production" ethernet ports (NFS) in different network subnet than my ups is, can I use BMC port for snmp communication with ups (since it's in a same subnet)?
BMC/RLM/SP can't be used for this as far as I know... if the same network you could IP alias or VLAN one of the ports on the 2020 to the same network as the UPS.