NFA requires some netflow fields in order to monitor routers
ALL NFA versions with all router models
1 - IN_BYTES or 85 – IN_PERMANENT_BYTES (NFA Only) : bytes in IP Flow.
4 - PROTOCOL : IP protocol
7 - L4_SRC_PORT : TCP/UDP source port
8 - IPV4_SRC_ADDR : IPV4 source address
10 - INPUT_SNMP : gives the IFindex of the IN interface
11 - L4_DST_PORT : TCP/UDP destination port
12 - IPV4_DST_ADDR : IPV4 destination address
14 - OUTPUT_SNMP : gives the IFindex of the OUT interface
For flexible netflow :
61 - direction :Flow direction: 0 - ingress flow, 1 - egress flow