---
title: NetFlow Monitor
description: >-
  Monitor network traffic flows on routers, switches, and firewalls to alert on
  throughput and congestion using NetFlow data.
breadcrumbs: Docs > Monitors > Monitor Types > NetFlow Monitor
---

# NetFlow Monitor

{% callout %}
##### Access the Preview!

The NetFlow monitor is in Preview. Reach out to your Datadog representative to sign up for access.
{% /callout %}

## Overview{% #overview %}

Datadog [Network Device Monitoring](https://docs.datadoghq.com/network_monitoring/devices/) (NDM) provides visibility into your on-premises and virtual network devices, such as routers, switches, and firewalls. As a part of NDM, [NetFlow Monitoring](https://docs.datadoghq.com/network_monitoring/netflow/) enables you to examine, interpret, and analyze your network traffic flow data over time, and identify top contributors to network congestion.

After enabling NetFlow Monitoring, you can create a NetFlow monitor to alert you when a flow metric (such as network throughput for a specific source or destination pair) crosses a threshold that you have set.

## Monitor creation{% #monitor-creation %}

To create a NetFlow monitor in Datadog, use the main navigation: [**Monitors** –> **New Monitor** –> **NetFlow**](https://app.datadoghq.com/monitors/create/netflow).

### Define the search query{% #define-the-search-query %}

As you define the search query, the top graph updates in real time.

{% image
   source="https://datadog-docs.imgix.net/images/monitors/monitor_types/netflow/monitor_2.cf567b92664a4cbc8edc1f4901d23251.png?auto=format"
   alt="Example monitor configuration using NetFlow data" /%}

1. Construct a search query using the same logic as the [NetFlow widgets](https://docs.datadoghq.com/network_monitoring/netflow/#visualization) in your dashboards.
1. Select if you want to alert on bytes or packets for traffic.
1. Choose the tags you want to filter the alerted traffic by. See the [full list of available facets](https://docs.datadoghq.com/network_monitoring/netflow/#visualization).

### Using formulas and functions{% #using-formulas-and-functions %}

You can create NetFlow monitors using formulas and functions. This can be used, for example, to create monitors on the volume of traffic sent by source and device.

{% image
   source="https://datadog-docs.imgix.net/images/monitors/monitor_types/netflow/formula_2.087d66c27c10b471f167a77008767ca5.png?auto=format"
   alt="Example monitor configuration using NetFlow data and a formula" /%}

For more information, see the [Functions](https://docs.datadoghq.com/dashboards/functions/) documentation.

### Set alert conditions{% #set-alert-conditions %}

Configure monitors to trigger if the query value crosses a threshold, and customize advanced alert options for recovery thresholds and evaluation delays. For more information, see [Configure Monitors](https://docs.datadoghq.com/monitors/configuration/).

### Notifications{% #notifications %}

For detailed instructions on the **Say what's happening** and **Notify your team** sections, see the [Notifications](https://docs.datadoghq.com/monitors/notify/) page.

## Monitor NetFlow events{% #monitor-netflow-events %}

For more information about events you can create NetFlow monitors on, see the [NetFlow Monitoring documentation](https://docs.datadoghq.com/network_monitoring/netflow/#visualization).

## Further Reading{% #further-reading %}

- [Learn more about NetFlow Monitoring](https://docs.datadoghq.com/network_monitoring/netflow/#visualization)
- [Configure your monitor notifications](https://docs.datadoghq.com/monitors/notify/)
- [Schedule a downtime to mute a monitor](https://docs.datadoghq.com/monitors/downtimes/)
- [Check your monitor status](https://docs.datadoghq.com/monitors/status/)