nProbe not reporting correctly to ntopng

nProbe yields different counters (traffic, ooo) to ntopng, depending on how it is executed.

pcap to reproduce available upon request.

Following is what happens:

sudo ./nprobe -i ../ntopng/../OOO_small.pcap --zmq tcp://127.0.0.1:5556 -T "@NTOPNG@" --json-labels

27/Mar/2019 16:33:05 [ParserInterface.cpp:658] [{"IN_SRC_MAC":"00:90:FB:33:B0:D5","OUT_DST_MAC":"00:23:7D:15:D3:C3","INPUT_SNMP":0,"OUTPUT_SNMP":0,"SRC_VLAN":0,"IPV4_SRC_ADDR":"172.16.11.56","IPV4_DST_ADDR":"100.7.81.1","L4_SRC_PORT":53720,"L4_DST_PORT":9080,"IPV6_SRC_ADDR":"::","IPV6_DST_ADDR":"::","IP_PROTOCOL_VERSION":4,"PROTOCOL":6,"L7_PROTO":"7","IN_BYTES":1586,"IN_PKTS":8,"OUT_BYTES":66602,"OUT_PKTS":37,"FIRST_SWITCHED":1553700768,"LAST_SWITCHED":1553700768,"CLIENT_NW_LATENCY_MS":0.000,"SERVER_NW_LATENCY_MS":0.000,"APPL_LATENCY_MS":0.000,"CLIENT_TCP_FLAGS":24,"SERVER_TCP_FLAGS":24,"OOORDER_IN_PKTS":0,"OOORDER_OUT_PKTS":8,"RETRANSMITTED_IN_PKTS":0,"RETRANSMITTED_OUT_PKTS":3,"HTTP_URL":"100.7.81.1:9080/ws-cae","HTTP_SITE":"100.7.81.1:9080","SSL_SERVER_NAME":"","BITTORRENT_HASH":"", "35632.57943":"192.168.2.222"},{"IN_SRC_MAC":"00:90:FB:33:B0:D5","OUT_DST_MAC":"00:23:7D:15:D3:C3","INPUT_SNMP":0,"OUTPUT_SNMP":0,"SRC_VLAN":0,"IPV4_SRC_ADDR":"172.16.11.56","IPV4_DST_ADDR":"100.7.81.1","L4_SRC_PORT":53720,"L4_DST_PORT":9080,"IPV6_SRC_ADDR":"::","IPV6_DST_ADDR":"::","IP_PROTOCOL_VERSION":4,"PROTOCOL":6,"L7_PROTO":"7","IN_BYTES":1546,"IN_PKTS":7,"OUT_BYTES":25700,"OUT_PKTS":20,"FIRST_SWITCHED":1553700768,"LAST_SWITCHED":1553700768,"CLIENT_NW_LATENCY_MS":0.000,"SERVER_NW_LATENCY_MS":0.000,"APPL_LATENCY_MS":0.000,"CLIENT_TCP_FLAGS":29,"SERVER_TCP_FLAGS":24,"OOORDER_IN_PKTS":0,"OOORDER_OUT_PKTS":3,"RETRANSMITTED_IN_PKTS":1,"RETRANSMITTED_OUT_PKTS":2,"HTTP_URL":"100.7.81.1:9080/ws-cae","HTTP_SITE":"100.7.81.1:9080","SSL_SERVER_NAME":"","BITTORRENT_HASH":"", "35632.57943":"192.168.2.222"}]

sudo ./nprobe -i ../ntopng/../OOO_small.pcap --zmq tcp://127.0.0.1:5556 -T "@NTOPNG@"

[{"56":"00:90:FB:33:B0:D5","57":"00:23:7D:15:D3:C3","10":0,"14":0,"58":0,"8":"172.16.11.56","12":"100.7.81.1","7":53720,"11":9080,"27":"::","28":"::","60":4,"4":6,"35632.57590":"7","1":1758,"2":12,"23":66618,"24":37,"22":1553700828,"21":1553700828,"35632.57595":0.007,"35632.57596":0.020,"35632.57597":0.640,"35632.57550":26,"35632.57551":26,"35632.57583":0,"35632.57584":5,"35632.57581":0,"35632.57582":8,"35632.57652":"100.7.81.1:9080/ws-cae","35632.57833":"100.7.81.1:9080","35632.57660":"","35632.57661":"", "35632.57943":"192.168.2.222"},{"56":"00:90:FB:33:B0:D5","57":"00:23:7D:15:D3:C3","10":0,"14":0,"58":0,"8":"172.16.11.56","12":"100.7.81.1","7":53720,"11":9080,"27":"::","28":"::","60":4,"4":6,"35632.57590":"7","1":1626,"2":9,"23":66522,"24":35,"22":1553700828,"21":1553700828,"35632.57595":0.000,"35632.57596":0.000,"35632.57597":0.000,"35632.57550":24,"35632.57551":24,"35632.57583":0,"35632.57584":8,"35632.57581":0,"35632.57582":2,"35632.57652":"100.7.81.1:9080/ws-cae","35632.57833":"100.7.81.1:9080","35632.57660":"","35632.57661":"", "35632.57943":"192.168.2.222"},{"56":"00:90:FB:33:B0:D5","57":"00:23:7D:15:D3:C3","10":0,"14":0,"58":0,"8":"172.16.11.56","12":"100.7.81.1","7":53720,"11":9080,"27":"::","28":"::","60":4,"4":6,"35632.57590":"7","1":1626,"2":9,"23":66762,"24":41,"22":1553700828,"21":1553700828,"35632.57595":0.000,"35632.57596":0.000,"35632.57597":0.000,"35632.57550":24,"35632.57551":24,"35632.57583":0,"35632.57584":10,"35632.57581":0,"35632.57582":3,"35632.57652":"100.7.81.1:9080/ws-cae","35632.57833":"100.7.81.1:9080","35632.57660":"","35632.57661":"", "35632.57943":"192.168.2.222"},{"56":"00:90:FB:33:B0:D5","57":"00:23:7D:15:D3:C3","10":0,"14":0,"58":0,"8":"172.16.11.56","12":"100.7.81.1","7":53720,"11":9080,"27":"::","28":"::","60":4,"4":6,"35632.57590":"7","1":1626,"2":9,"23":66682,"24":39,"22":1553700828,"21":1553700828,"35632.57595":0.000,"35632.57596":0.000,"35632.57597":0.000,"35632.57550":24,"35632.57551":24,"35632.57583":0,"35632.57584":8,"35632.57581":0,"35632.57582":2,"35632.57652":"100.7.81.1:9080/ws-cae","35632.57833":"100.7.81.1:9080","35632.57660":"","35632.57661":"", "35632.57943":"192.168.2.222"},{"56":"00:90:FB:33:B0:D5","57":"00:23:7D:15:D3:C3","10":0,"14":0,"58":0,"8":"172.16.11.56","12":"100.7.81.1","7":53720,"11":9080,"27":"::","28":"::","60":4,"4":6,"35632.57590":"7","1":1626,"2":9,"23":66602,"24":37,"22":1553700828,"21":1553700828,"35632.57595":0.000,"35632.57596":0.000,"35632.57597":0.000,"35632.57550":24,"35632.57551":24,"35632.57583":0,"35632.57584":8,"35632.57581":0,"35632.57582":2,"35632.57652":"100.7.81.1:9080/ws-cae","35632.57833":"100.7.81.1:9080","35632.57660":"","35632.57661":"", "35632.57943":"192.168.2.222"},{"56":"00:90:FB:33:B0:D5","57":"00:23:7D:15:D3:C3","10":0,"14":0,"58":0,"8":"172.16.11.56","12":"100.7.81.1","7":53720,"11":9080,"27":"::","28":"::","60":4,"4":6,"35632.57590":"7","1":1586,"2":8,"23":66602,"24":37,"22":1553700828,"21":1553700828,"35632.57595":0.000,"35632.57596":0.000,"35632.57597":0.000,"35632.57550":24,"35632.57551":24,"35632.57583":0,"35632.57584":8,"35632.57581":0,"35632.57582":3,"35632.57652":"100.7.81.1:9080/ws-cae","35632.57833":"100.7.81.1:9080","35632.57660":"","35632.57661":"", "35632.57943":"192.168.2.222"},{"56":"00:90:FB:33:B0:D5","57":"00:23:7D:15:D3:C3","10":0,"14":0,"58":0,"8":"172.16.11.56","12":"100.7.81.1","7":53720,"11":9080,"27":"::","28":"::","60":4,"4":6,"35632.57590":"7","1":1546,"2":7,"23":25700,"24":20,"22":1553700828,"21":1553700828,"35632.57595":0.000,"35632.57596":0.000,"35632.57597":0.000,"35632.57550":29,"35632.57551":24,"35632.57583":0,"35632.57584":3,"35632.57581":1,"35632.57582":2,"35632.57652":"100.7.81.1:9080/ws-cae","35632.57833":"100.7.81.1:9080","35632.57660":"","35632.57661":"", "35632.57943":"192.168.2.222"}]

sudo ./nprobe -i ../ntopng/../OOO_small.pcap --zmq tcp://127.0.0.1:5556 -T "@NTOPNG@" --zmq-disable-buffering

27/Mar/2019 16:37:08 [ParserInterface.cpp:658] {"56":"00:90:FB:33:B0:D5","57":"00:23:7D:15:D3:C3","10":0,"14":0,"58":0,"8":"172.16.11.56","12":"100.7.81.1","7":53720,"11":9080,"27":"::","28":"::","60":4,"4":6,"35632.57590":"7","1":1546,"2":7,"23":25700,"24":20,"22":1553701021,"21":1553701021,"35632.57595":0.000,"35632.57596":0.000,"35632.57597":0.000,"35632.57550":29,"35632.57551":24,"35632.57583":0,"35632.57584":3,"35632.57581":1,"35632.57582":2,"35632.57652":"100.7.81.1:9080/ws-cae","35632.57833":"100.7.81.1:9080","35632.57660":"","35632.57661":"", "35632.57943":"192.168.2.222"}

Start by reproducing the discrepancy with OOO_small.pcap using the three nProbe commands shown, comparing the traffic and out-of-order counters sent to ntopng. Check how --json-labels and --zmq-disable-buffering affect the emitted records; done means the counters are consistent across execution modes.