NetFlow

Synopsis

Creates a NetFlow collector that accepts flow data over UDP connections. Supports high-volume collection with multiple workers and configurable buffer sizes.

warning

The collector only supports legacy NetFlow types, such as NetFlow v5. For NetFlow v9, use the ipfix collector type.

For details, see Appendix.

Schema

- id: <numeric>
  name: <string>
  description: <string>
  type: netflow
  tags: <string[]>
  pipelines: <pipeline[]>
  status: <boolean>
  properties:
    address: <string>
    port: <numeric>
    workers: <numeric>
    reuse: <boolean>

Configuration

The following fields are used to define the device:

Device

Field	Required	Default	Description
`id`	Y		Unique identifier
`name`	Y		Device name
`description`	N	-	Optional description
`type`	Y		Must be `netflow`
`tags`	N	-	Optional tags
`pipelines`	N	-	Optional pre-processor pipelines
`status`	N	`true`	Enable/disable the device

Connection

Field	Required	Default	Description
`address`	N	`"0.0.0.0"`	Listen address
`port`	N	`2055`	Listen port
`workers`	N	CPU count	Number of worker goroutines
`reuse`	N	`false`	Enable socket address reuse

Details

NetFlow, sFlow, and IPFIX devices share a common flow collection backend (backend/module/listener/flow/). The thin per-protocol controller sets the flow type and default port.

When reuse is enabled, the collector spawns multiple workers which maintain their own UDP listeners, process flows independently, and write to dedicated queue files. The collector scales up to use all available CPU cores.

The collector supports fixed format NetFlow v5 records, application identification, port-based protocol mapping, flow state tracking, and statistical aggregation.

Examples

The following are commonly used configuration types.

Basic

Creating a simple NetFlow v5 collector on the default port...

devices:
  - id: 1
    name: basic_netflow
    type: netflow
    properties:
      port: 2055

High-Volume

Optimizing for high flow volumes using multiple workers...

devices:
  - id: 2
    name: performant_netflow
    type: netflow
    properties:
      address: "0.0.0.0"
      port: 2055
      reuse: true
      workers: 4

Application Protocols

The collector supports application-based identification, TCP port mapping, and UDP port mapping. The definition files for these respectively are placed in three locations under <vm_root>:

/user/definitions/app-definitions-{device-id}.csv (device-specific)
/user/definitions/app-definitions.csv (user-defined)
/package/definitions/app-definitions.csv (system defaults)
/user/definitions/tcp-definitions-{device-id}.csv (device-specific)
/user/definitions/tcp-definitions.csv (user-defined)
/package/definitions/tcp-definitions.csv (system defaults)
/user/definitions/udp-definitions-{device-id}.csv (device-specific)
/user/definitions/udp-definitions.csv (user-defined)
/package/definitions/udp-definitions.csv (system defaults):::warning

Definition files must be in CSV format with exactly two columns per row. :::

The contents of these files are:

app-definitions.csv:

SSH,Secure Shell
RDP,Remote Desktop
HTTP,Web Browsing
HTTPS,Secure Web

tcp-definitions.csv:

22,SSH
3389,RDP
80,HTTP
443,HTTPS

udp-definitions.csv:

53,DNS
67,DHCP
123,NTP
161,SNMP

note

The collector will fall back on the system defaults if the custom definition files are not found.

NetFlow collector with application identification enabled...

devices:
  - id: 3
    name: app_aware_netflow
    type: netflow
    properties:
      port: 2055
      reuse: true

Synopsis​

Schema​

Configuration​

Device​

Connection​

Details​

Examples​

Basic​

High-Volume​

Application Protocols​