Skip to main content
Version: 2.10.0

GCP Top Traffic Monitor (10367 / 20367)


This Module identifies GCP VM instances with the most traffic. It consolidates VPC Flow Logs records over a period of time (Data Collection Interval) which all have the same combination of the following fields:

  • Source IP address
  • Destination IP address
  • Source port number
  • Destination port number
  • Layer 3 protocol
  • Reporter

This information is provided per Subnetwork. The Module also enriches them with GCP data not reported in base VPC Flow Logs (when metadata fields are disabled).

De-duplication: optionally the Module can report consolidated flows only from authoritative Subnetwork. Authoritative Subnetwork is determined as follows. The Module sums up bytes, packets, and connections between two GCP VM instances over data collection interval reported by each Subnetwork. A Subnetwork with most connections (flows) for each consolidated flow is considered authoritative, and flows reported for the same two GCP VM instances by all other Subnetworks are discarded.


Parameter NameDescriptionComments
Data Reporting Interval, secModule logic execution intervalmin = 5 sec, max = 1800 sec, default = 30 sec
N – number of reported hostsThe number of top hosts reported per NetFlow exportermin = 0, max = 100000, default = 50 (0 indicates all hosts are reported)
Share of total traffic reported, %Reported percent of total traffic per VPCe.g. 98 - indicates that reported consolidated flows consuming 98% of total NetFlow exporter traffic; min = 1%, max = 100%, default = 95%. Not more than N consolidated flows will be reported
Enable(1) or disable (0) reporting by authoritative exporters onlyIf set to 1 (de-duplication enabled), the Module reports flows only from authoritative VPCs (exporters)default = 0
Compute Engine VM InstancesVMs with IPs, project ID, zone, name, and VPC namesProvided by EDF agent
Compute Engine IPv4 RoutesIP range, source and destination subnetwork IDs, Subnetwork nameProvided by EDF agent


GCP Flow Logs

Syslog/JSON Message Fields​

KeyField DescriptionComments
nfc_idMessage type identifierβ€œnfc_id=20367”
exp_ipNetFlow exporter Ipv4 address<IPv4 address> (added for compatibility with other flows)
reporterGCP VPC Flow logs Reporter<string>, "SRC" or "DEST"
gcp_expGCP VPC Flow logs Exporter. Calculated field based on reporter = SRC or DEST<string>, "Project ID/VPC/Subnet"
protocolTransport Protocol ( TCP = 6, UDP = 17)<number>
src_ipSource host IPv4 address<IPv4 address>
[src_ip6]Source host Ipv6 address<IPv6 address>
[src_host]Source host name<string>, included when FQDN is on
[src_project_id]Source Project ID<string>
[src_vm_name]Source VM name<string>
[src_vm_zone]Source VM Zone<string>
[src_vpc_name]Source VPC Name<string>
src_portSource port number<number>
dest_ipDestination host IPv4 address<IPv4 address>
[dest_ip6]Destination host IPv6 address<IPv6 address>
[dest_host]Destination host name<string>, included when FQDN is on
[dest_project_id]Destination Project ID<string>
[dest_vm_name]Destination VM name<string>
[dest_vm_zone]Destination VM Zone<string>
[dest_vpc_name]Destination VPC Name<string>
dest_portDestination EC2 instance port number<number>
tcp_flagTCP Flags<string>, e.g. β€œSYN,ACK,FIN”
packets_inPackets in the flow<number>
bytes_inTotal number of Layer 3 bytes in the packets of the flow received<number>
flow_countNumber of consolidated Flows<number>
percent_of_totalPercent of Total (bytes)<decimal>, e.g. 25.444% is 25.444
subnet_idSubnet ID<string>
flow_start_timeStart time of the first consolidated flow<time>
flow_end_timeEnd of the last consolidated flow<time>
t_intObservation time interval, msec<number>