The MAC address is not stored from NetFlow data in NTA. The Data that is stored in NTA is as follows:
Field Type Field Type Number Description IN_BYTES 1 Ingress bytes counter IN_PKTS 2 Ingress Packets counter PROTOCOL 4 Layer 4 Protocol L4_SRC_ PORT 7 Source TCP/UDP Port IPV4_SRC_ADDR 8 Source IP address L4_DST_PORT 11 Destination TCP/UDP Port IPV4_DST_ADDR 12 Desintation IP address OUTPUT_SNMP 14 SNMP egress interface index
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