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The Best Free sFlow Collectors and Analyzers to Monitor your Network
UPDATED: November 26, 2024
Utilizing sFlow collectors and analyzers are essential as our reliance on network connectivity and the need for faster, reliable data transfer speeds grows. Network administrators are under a lot of stress to ensure their network is performing at its peak. Even the smallest changes on a network can affect its performance and reliability.
Here is our list of the best free sFlow collectors and analyzers to monitor your network:
- ManageEngine NetFlow Analyzer – EDITOR'S CHOICE This bandwidth analyzer includes traffic monitoring systems that can interpret sFlow, J-Flow, NetFlow, IPFIX, NetStream, and AppFlow messaging. Installs on Windows Server and Linux. Start a 30-day free trial.
- Paessler PRTG – FREE TRIAL A collection of monitoring tools that includes a network traffic data collection sensor that specifically communicates with sFlow. Installs on Windows Server. Start a 30-day free trial.
- Site24x7 – FREE TRIAL Offers intuitive real-time collection and analysis of sFlow data, complete with customizable alerts, sFlow analysis, and in-depth reporting making it an essential asset for network administrators and IT professionals monitoring network traffic. Start a 30-day free trial.
- sFlowTrend by inMon This specialist sFlow communicator is free to use and will help you sample traffic flow data from switches. Available for Windows and Linux.
- Plixer Scrutinizer This is the free version of a traffic sampling tool from Plixer. A paid version with more features is also available. Installs on top of Hyper-V.
- nTop A respected free traffic analyzer that can communicate through sFlow and NetFlow. Installs on Windows.
- SolarWinds NetFlow Traffic Analyzer Bandwidth analysis systems package that can communicate with network devices through sFlow, NetFlow, J-Flow, NetStream, and IPFIX.
- Wireshark Packet capture system that can communicate through sFlow and NetFlow. Installs on Windows and macOS.
- Intermapper A network traffic analyzer that can be extended to use traffic flow protocols sFlow, J-Flow, and NetFlow. Installs on Windows, macOS, and Linux.
The sFlow protocol was designed to operate on the Layer2 level of the OSI model, and it comes embedded in a software process in switches and routers. The sFlow Agent combines interface counters and flow samples, embeds them into an sFlow Datagram, and sends them on to an sFlow Collector.
This information is used by network administrators to monitor and analyze network traffic via a free network analyzer tool in order to find issues and to stop them before they become major problems. sFlow data can help pinpoint network bottlenecks, bandwidth hogs, and network problems, and the data contributes to helping the constant effort to improve network reliability.
The same sFlow data is also used by network security engineers to search for abnormal traffic patterns, such as large file transfers to a remote server or an unusually high number of connections to a local host initiated at once.
The Best sFlow Collectors and Analyzers
Our methodology for sFlow collectors and analyzers
We reviewed various sFlow collectors and analyzers and analyzed the options based on the following criteria:
- Support for various flow protocols (sFlow, NetFlow, etc)
- Ease of use
- Graphical interpretation of data, such as charts and graphs
- Free trial period, a demo, or a money-back guarantee for no-risk assessment
- Good price that reflects value for money when compared to the functions offered
Pros:
- Monitor Multiple Sites: Control and monitor multiple remote sites from one center location to ensure their smooth operation.
- Automated Network Reports: Conducts detailed analysis and generates reports automatically. Users can also schedule report generation at specific times and select criteria to receive reports directly by email.
- Fast Network Troubleshooting: Users can quickly take action on both present and past issues to drill deeper into network elements and fix the issue.
- Customizable Dashboard: Users can customize the dashboard using parameters and widgets that can be dragged and dropped and easily used for analysis.
Cons:
- Complex Firewall Implementation: Users find WAN devices difficult to manage, and while firewall configuration, every module requires a separate cost, which is quite expensive.
After the free 30-day trial, ManageEngine allows for the monitoring of two interfaces.
EDITOR'S CHOICE
ManageEngine NetFlow Analyzer is our top pick for a free sFlow collector and analyzer because you can get a Free edition of this traffic monitor for networks. The package includes an sFlow collector, but that’s not all. It also provides NetFlow, IPFIX, J-Flow, Netstream, and AppFlow capabilities, which enables it to query traffic statistics from a range of network device brands. This is very useful if you have devices from different brands on your network because they are likely to be loaded with different protocols. Another avenue this package offers for traffic analysis is packet capture. The tool can summarize all of the data it extracts by attributes, such as top talkers according to source or destination and the system implements Cisco NBAR for protocol analysis. Typical uses for this system include bottleneck detection, traffic shaping assessment, and network capacity planning. This bandwidth analyzer has a free trial as well as a free edition. You get a lot more functionality out of the free trial of the paid edition than you do from the Free edition. However, that full version is only free for 30 days. The Free plan is limited to monitoring only two interfaces.
Download: Get a 30-day free trial
Official Site: manageengine.com/products/netflow/
OS: Windows Server, Linux, AWS
2. Paessler PRTG – FREE TRIAL
Paessler PRTG comes with many useful features that allow you to collect sFlow data and use it to troubleshoot and improve your network. Its highly customizable suite of sensors allows you to configure which data from which devices that you will collect.
Key Features:
- Data and Traffic Monitoring: Monitors heavily used computers, their processes, and data exchange to understand the problem and professionally fix it.
- sFlow Technology: sFlow is basically a sampling technology, similar to CISCO. It collects detailed data regarding CPU load and bandwidth consumption.
- 24/7 Network Monitoring: Quickly catch bottlenecks, suspicious traffic, and server downtime to optimize the network and have a productive workflow.
- Information Dashboard: Captures sflow packets and subsequent amount of data, user can also configure the data according to its consumption.
PRTG supports LAN, WAN, and VPN flow monitoring and collection, as well as the capability to do in-depth reporting with over 30 report templates, such as Uptime/Downtime, Top 100 Bandwidth Usage, Top 100 Disk Space, and more. It includes a multi-language interface as well as options for different types of alerts, including push notifications to your mobile device.
Pros:
- Send Automatic Alerts: Users can always stay updated via SMS, email, or push messages when network problems or protocol failures occur.
- Instant Troubleshooting: With active alerts and detailed display information for problems, you can easily fix network errors and protocol issues quickly.
- Scalable: Allows to detect the programs that are consuming more bandwidth and scale the bandwidth according to network traffic.
- Detailed Traffic Visualization: Users can see detailed traffic visualization to easily understand the correlation between networks and detect suspicious malware or threats.
Cons:
- Slower Installations: Many users noticed slower installation and increased page load times with more sensors.
PRTG offers a free 30-day trial with unlimited sensors, then 100 sensors for an unlimited amount of time after that.
3. Site24x7 – FREE TRIAL
In the realm of network management, particularly when dealing with sFlow data for performance monitoring, Site24x7 emerges as a competent and reliable tool. sFlow is essential for understanding network usage patterns, pinpointing bottlenecks, and ensuring efficient network performance. Site24x7 offers an intuitive way to collect and analyze sFlow data, making it a valuable asset for network administrators and IT professionals who need to monitor network traffic in real time.
Key Features:
- Comprehensive Network Control: Gives granular visibility about devices and other interfaces that are using network bandwidth hence users can observe the important parameters for a better network control.
- Network Traffic Monitoring: Admins can use different networking technologies to analyze traffic trends and bandwidth usage and troubleshoot active issues instantly.
- Traffic Organization: Users can also extract reports in tabular form or graphs for easy interpretation and export in multiple formats.
- Router and VPN Monitoring: Users can track VPN latency, paths, and connections and monitor router activities and bandwidth allocation.
Why do we recommend it?
We recommend Site24x7 as it provides an integrated platform for sFlow data analysis, offering real-time insights and detailed reports. Its ability to handle large volumes of data with ease makes it stand out in the category of free sFlow collectors and analyzers.
Who is it recommended for?
Site24x7 is particularly suited for network administrators and IT professionals in medium to large enterprises who require a robust and scalable solution for network traffic monitoring. Its comprehensive features cater to those who need in-depth traffic analysis and real-time monitoring for complex network environments.
Pros:
- Exclusive Dashboards: Notifies you about top and high-bandwidth users so that you can organize network traffic and volume accordingly.
- Detects Traffic Anomalies: Drill down deeply and analyze IP addresses to identify actual network anomalies for seamless workflow.
- Data Optimization: Identify network pinpoints and block or restrict the app or device to optimize data across the network.
- Get Notified About the Busy Interface: Specify particular device limits by setting up conditions to prevent heavy traffic and receive alerts for breaches and suspicious activities.
Cons:
- Improvement for Chat Support: Users find poor chat support when they need instant help or have queries.
4. sFlowTrend by inMon
sFlowTrend is a free server-monitoring tool that uses the sFlow standard to generate real-time displays of network bandwidth usage and of the top users and applications that are using this bandwidth. It allows you to rapidly find and identify the causes of problems on the network so that you can fix them before they become major problems.
Key Features:
- Network User Tracking: Observe who is using your network and what they are up to, helping you see whether someone is hogging the bandwidth or doing anything they shouldn't.
- Troubleshooting Made Easy: If something is wrong with your network, sFlowTrend can help you rapidly determine what is causing the problem. You can detect unexpected traffic or device problems quickly.
- Keep an Eye on Hosts: Allows you to keep track of critical information such as how much CPU or RAM your devices are using. This allows you to identify any performance concerns before they become major difficulties.
- Reports for Management: Allows you to build reports that demonstrate how your network is operating today and in the past. This lets you keep your superiors or team informed about what is happening.
With sFlow Trend, network administrators can also monitor critical host performance parameters, such as CPU usage and memory usage. Its graphical reports provide crucial information on current and historical performance, allowing you to identify bottlenecks, bandwidth hogs, and other troublemakers on your network.
Its simple installation and setup let you use less time on configuration and more time helping you improve your network. sFlowTrend supports Windows 32-bit and 64-bit OS’s, as well as Mac OS X, and Linux.
Pros:
- Free Server Monitoring: Entirely free and suitable tool for network analysis for most businesses that are restricted to budget.
- Clear Visuals: Shows data using simple images which is easy to understand by users to quickly grasp and evaluate network information.
- Cross-Platform Compatibility: You can use the sFlowTrend tool on Windows, Mac, and Linux.
Cons:
- UI Overhaul Needed: Some users might find the user interface in need of an update or redesign for improved usability and aesthetics.
The free version provides support of up to five switches or hosts and stores one hour of data; with the sFlowTrend Pro version, there is not limit to the number of hosts or the amount of stored data. For more information and to download, please click here.
5. Plixer Scrutinizer Free
Scrutinizer is a powerful free network traffic analysis tool that uses sFlow, along with other flow technology protocols, to collect and analyze network traffic. It allows you to troubleshoot your congested network by identifying problem stations, switches, routers, and other devices and applications.
Key Features:
- Application and DNS insights: Helps to check on complete insights related to network and security to make sure no blind or suspicious spots are present in the environment.
- Plixer Replicator: Duplicate and forward the crucial data to get more deeper insights and understand the other parts of network analytics.
- Full NDR Solution: Includes an NDR solution, which involves tracking the problem's root cause without compromising network performance.
- Advanced Performance Monitoring: With the help of comprehensive data and visibility, users can manage and optimize the IT environment.
Scrutinizer allows you to filter in on specific traffic in a number of ways, including a time frame, host, application, protocol, and much more.
Pros:
- Digital Experience Monitoring: By using network insights, users can analyze root cause analysis, optimize the application performance, and have a better response time.
- Predictive Planning: Uses machine learning, which helps in predictive planning, allowing predicting and planning changes for capacity, cloud migration, or infrastructure upgrades.
- Network Anomaly Detection: Advanced analytics so that users can understand traffic patterns better which could lead to network issues and other interruptions.
- Cloud Visibility: Track critical cloud infrastructure and flow logs across on-premise, cloud, and hybrid environments to actively track performance.
Cons:
- Free Version Doesn't Work Well: Many users tried the free version of Plixer Scrutinizer but found it gave inaccurate data and did not perform well as compared to the paid version.
This free edition allows for the collection of flows from unlimited devices and up to 10,000 flows per second, and stores up to 5 hours of data. Paid editions support flow collection of up to 8 million flows per second and unlimited history storage. For more information and to download, please click here.
6. nTop
nTop comes with powerful sFlow capture and analysis capabilities via its nProbe tool. It captures sFlow flows and converts them into “standard” flows, which it uses to generate reports and analyses.
Key Features:
- Packet Capture: No need to patch the kernel; it has a PF_RING, which is basically a network socket that helps improve packet capture and speed.
- Traffic Recording and Replay: Traffic recording applications such as n2disk for recording traffic packets and disk2n for replay network traffic from a live interface.
- Deep Packet Inspection: nDpl was released under the LGPL license, which helps in deep packet and traffic inspection; users can simply disable certain options that are unnecessary and make the DPI engine slow.
- DDOS Mitigation and VPN: Comes with a nScrub DDOS mitigation system which uses algorithms for network traffic mitigation.
What’s more is that it can capture any combination of flows on networks that use different devices like Cisco routers and switches, which use NetFlow. It combines these flows into integrated reports so that users do not have to sort through different data collected from different devices with different flow technologies.
Other features include IPv6 support, packet capture and sampling, VoIP traffic analysis, fully user configurable, and more.
Pros:
- Alerts for Cyber Incidents: Shows real-time traffic and active hosts, collects data and sends notifications to admin via email, discord, telegram and other linked apps.
- Detailed Inspection of Network Elements: With the help of an extensive LGPLv3 deep packet inspection library, users can get reports about metadata such as URL, TLS certificate, OS, and much more.
- 360-Degree Visualization: Stay updated with a holistic visualization by collecting information from SNMP devices, NetFlow exporters, intrusion detection systems, firewalls, and much more.
- Seamless Integration: Integrate this tool with other legitimate applications to get suitable data.
Cons:
- Constant Updates: As this tool is constantly updating, users might find it difficult to use the functionality with the upgrade of advanced features.
This popular and very powerful sFlow collector and network analyzer is definitely worth trying out. For more information and to download, please click here.
7. SolarWinds NetFlow Traffic Analyzer
This free sFlow Collector Tool from SolarWinds is one of the best and most popular sFlow collectors available. This tool allows you to sort, graph, and display data in various ways that allow you to easily visualize and analyze your network traffic.
Key Features:
- Bandwidth Monitoring: Admins can easily use various applications, protocols, and IP address groups to monitor bottlenecks of network bandwidth usage and create reports accordingly.
- Traffic Analysis: Helps identify problems in applications across the network. Network traffic analysis software allows users to collect data about comprehensive network elements to understand traffic patterns.
- Netflow Collector: Analyzes the entire network traffic using flow-based monitoring that helps to understand the correlation of data and traffic patterns via cross-stack metrics.
- Network Congestion: Run a network congestion test to identify the pinpoints and endpoints that consume more bandwidth and resolve network problems quickly.
This information can be used to identify which users, applications, and protocols are using the most bandwidth over a particular amount of time, and to find traffic patterns, which can be used to optimize network conditions during high-use periods.
SolarWinds NTA lets you drill down to a particular moment when something happened, which is invaluable for troubleshooting purposes. Its query function can be invaluable when working to pinpoint problems, and its real-time reporting and summaries provide important performance metrics that can ultimately help you save money by maximizing your network’s performance.
Pros:
- Get a Comprehensive Network Picture: Users can optimize network traffic by analyzing a comprehensive view of the network, such as source, destination, volume, congestion points, and much more.
- Great Visibility: Collects data regarding network traffic for applications and devices, which is translated into a chart and table, making it easier to understand.
- Traffic Alerts: Send custom alerts about the application using more bandwidth and causing network traffic.
- Performance Analysis Dashboard: Helps admins that helps admins make essential changes to optimize traffic and bandwidth.
Cons:
- Poor Organization of Menu and Less Intuitive: Some users find the tool's menu bar messy and unfriendly. This causes confusion when trying to find a suitable functionality or option.
Its interface is easy to use and the data is collected and graphed in easy-to-read formats. SolarWinds NetFlow Traffic Analyzer’s sFlow Collector is an essential free tool for any network administrator.
8. Wireshark
Wireshark is a powerful, free, open-source network flow collector and analyzer. Using the sFlow sampling technology, Wireshark can capture and display detailed packet data for a network administrator or network security engineer to analyze.
Key Features:
- Packet Capture and Analysis: Users can capture and analyze network traffic from previously recorded captures. It displays precise information about each packet, such as where it is coming from, where it is going, the type of data it carries, and more.
- Protocol Dissection: Breaks down and understands many different network protocols, helping you to understand how data is moving through a network, helpful for security purposes.
- Filters and Search: Powerful filtering and search options which allow users to focus on certain packets or patterns that they are interested in for detecting suspicious activity or discovering specific network occurrences.
- Traffic Analysis and Statistics: Tracks detailed stats about your network traffic, such as how fast data is moving if any packets are getting lost, how long it takes for data to travel from one point to another, and more.
Packet data can be filtered and colorized by categories to better read the data as it comes in, and that data can be saved and searched for future reference. It supports flow data capture from any number of wired, wireless, and virtual interfaces. Wireshark also supports different flow standards, such as NetFlow, jFlow, and all other major flow standards.
It comes with a graphical UI as well as a text-only interface, TShark, which allows for scripting. It supports Windows XP and higher, as well as OS X, Linux, and others.
Pros:
- Network Troubleshooting: Best networking tool for diagnosing and solving network issues because users can easily pinpoint configuration errors, network congestion, and faulty devices by analyzing packet captures.
- Collaboration and Integration: Easily share packet captures and analysis sessions; hence, with effective collaboration, fixing network and security issues becomes easier.
- Extensibility and Customization: Create custom plugins to meet your security-specific needs and enhance the tool's functionality.
- Protocol Dissection: Analyze a wide range of network protocols to get detailed insights such as network behavior at a granular level, threat detection and mitigation.
Cons:
- Difficulty in Analyzing Encrypted Packets: Many users find it difficult to analyze encrypted packets because they need suitable encryption and decryption techniques to analyze certain types of network traffic.
Wireshark is a must-try free tool for any network administrator. For more information and to download, please click here.
9. Intermapper
Intermapper is an industrial-strength network monitoring, mapping, and alerting application designed to help you manage your network and keep it at its optimum performance level.
Key Features:
- Real-Time Flow Monitoring: Complete picture of the network as it collects live metrics and data.
- Netflow, sflow, jflow and cflow Analysis: Detailed information of traffic and monitor Netflow, sflow, jflow and cflow which gives data about frequently visited sites, downloaded data and much more.
- DDOS Attack Information: Shows insights about IPS connected to a high number of hosts, users can check details about DDOS attack for faster response.
- Real-Time Netflow Data: Represent real-time data in the form of charts for easy understanding. Moreover, it also provides forensic data regarding compliance purposes.
Intermapper’s integrated network analyzer tool collects historical network flow data and saves it for you to identify current and past network activity trends; its interface allows you to easily chart this data in ways that makes it easy to visualize.
Using sFlow data, Intermapper helps you address security concerns such as identifying your Top Talkers, which websites were visited most often, which local IP addresses are connecting to an unusually large number of hosts, and which devices uploaded unusually large files to an off-site host.
Real-time flow monitoring, bandwidth monitoring, and network mapping capabilities are some of the many features included in Intermapper. You can also capture new network devices as they connect to the network. Intermapper scans your network to show any outbound devices that have connected, giving you a more accurate picture of all Layer 3 devices on your network, so you can add new devices to the maps for continued monitoring.
New device discovery helps enhance your network security and gives you awareness of what’s connected to your network at all times.
Pros:
- Auto-Discovery Capability: Helps to automatically discover new devices on the network which helps users to add and monitor new network components.
- SLA Compliance Reporting: Provides SLA (Service Level Agreement) compliance reporting, very useful for MSPs and bigger networks.
- Cross-Platform Compatibility: Compatible with Windows, Linux, and Mac operating systems, enabling flexibility and accessibility across multiple platforms.
Cons:
- Outdated Interface: Some users consider this tool outdated because its absence of new design components can affect user experience and efficiency when using the software.
- Limited Visual Options: Graphical options are rather limited, which may limit the capacity to adapt and visualize data based on user preferences.
More info here. Download a free 30-day trial
Conclusion
That concludes our list of sFlow software that we recommend to anyone looking to monitor their network devices that are capable of it. With sFlow technology, we are able to make our networks faster, more reliable, and more secure.
This list of the Best sFlow Collectors and Analyzers will let you easily implement this technology on your network so that you can quickly start taking advantage of its benefits.
Free sFlow Collectors and Analyzers FAQs
Why use an sFlow collector?
sFlow collectors are used to monitor network traffic and performance, and provide valuable information about network utilization, traffic patterns, and security threats. By using an sFlow collector, organizations can gain a more complete view of their network traffic and performance, allowing them to make informed decisions about network management and security.
What are the key features of an sFlow collector?
The key features of an sFlow collector include:
- Data aggregation: The ability to collect and aggregate sFlow data from multiple network devices into a centralized repository.
- Data analysis and reporting: The ability to analyze and report on the collected sFlow data, providing valuable insights into network performance and utilization.
- Scalability: The ability to support the collection of sFlow data from large and complex network environments.
- Integration with other tools: The ability to integrate with other network monitoring and management tools, such as network analyzers and security information and event management (SIEM) systems.
1. ManageEngine NetFlow Analyzer – FREE TRIAL
ManageEngine NetFlow Analyzer is a full-featured application designed to give you a comprehensive view of your network’s performance using sFlow information, as well as other flow protocols, such as NetFlow and jFlow.
Key Features:
Its real-time bandwidth monitoring lets you find and identify problem-causing devices on your network, and it provides you with the ability to set threshold alarms for set bandwidth usage. Usage summaries, application, and protocol monitoring give you a comprehensive analysis of your network’s performance that helps you keep your network running at peak performance.
NetFlow Analyzer boasts the ability to define departments based on IP addresses, site-to-site traffic monitoring that helps you understand network traffic behavior between two defined sites, and also lets you manage devices by grouping them into logical groups and then monitor traffic for just those groups.
These crucial features, and many more, are a network administrator’s best friends.