1. GFI LanGuard (our award-winning paid solution)
People say it’s good to be modest and not to brag, but we’re so proud of our network management tool that we had to start the list with GFI LanGuard. You can use it to scan both small and large networks, in search of software vulnerabilities and unpatched or unlicensed applications. Information coming from up to 60,000 devices, running on Windows, Mac OS or Linux, will be shown in a centralized web console, so you’ll be able to see the state of your whole network at any moment and from any location.
With centralized patch management and network auditing, GFI LanGuard prevents potential compliance issues, but if you’re a sysadmin the fact that all machines are patched and secured will surely seem like a more important advantage. But, don’t take our word for it, download the free trial and try it out.
2. Microsoft Network Monitor
Microsoft Network Monitor is a packet analyzer that allows you to capture, view and analyze network traffic. This tool is handy for troubleshooting network problems and applications on the network. Main features include support for over 300 public and Microsoft proprietary protocols, simultaneous capture sessions, a Wireless Monitor Mode and sniffing of promiscuous mode traffic, amongst others.
When you launch Microsoft Network Monitor, choose which adapter to bind to from the main window and then click “New Capture” to initiate a new capture tab. Within the Capture tab, click “Capture Settings” to change filter options, adapter options, or global settings accordingly and then hit “Start” to initiate the packet capture process. Although very useful, this tool has been archived, and now Microsoft recommends using Message Analyzer for the same purpose.
3. Nagios
Nagios is a powerful network monitoring tool that helps you to ensure that your critical systems, applications and services are always up and running. It provides features such as alerting, event handling and reporting. The Nagios Core is the heart of the application that contains the core monitoring engine and a basic web UI. On top of the Nagios Core, you are able to implement plugins that will allow you to monitor services, applications, and metrics, a chosen frontend as well as add-ons for data visualisation, graphs, load distribution, and MySQL database support, amongst others.
Tip: If you want to try out Nagios without needing to install and configure it from scratch, download Nagios XI and enable the free version. Nagios XI is the pre-configured enterprise class version built upon Nagios Core and is backed by a commercial company that offers support and additional features such as more plugins and advanced reporting.
Note: The free version of Nagios XI is ideal for smaller environments and will monitor up to seven nodes.
Once you’ve installed and configured Nagios, launch the Web UI and begin to configure host groups and service groups. Once Nagios has had some time to monitor the status of the specified hosts and services, it can start to paint a picture of what the health of your systems look like.
4. OpenNMS
OpenNMS is an open source enterprise grade network management application that offers automated discovery, event and notification management, performance measurement, and service assurance features. OpenNMS includes a client app for the iPhone, iPad or iPod Touch for on-the-go access, giving you the ability to view outages, nodes, alarms and add an interface to monitor.
Once you successfully login to the OpenNMS web UI, use the dashboard to get a quick ‘snapshot view’ of any outages, alarms or notifications. You can drill down and get more information about any of these sections from the Status drop down menu. The Reports section allows you to generate reports to send by e-mail or download as a PDF.
5. Advanced IP Scanner
Advanced IP Scanner is a fast and easy to use network scanner that detects any network devices (including wireless devices such as mobile phones, printers and WIFI routers) on your network. It allows you to connect to common services such as HTTP, FTP and shared folders if they are enabled on the remote machine. You are also able to wake up and shut down remote computers.
The installer allows you to fully install the application on your machine or run the portable version. When you launch Advanced IP Scanner, start by going to Settings > Options to select which resources to scan and how fast/accurate you want the results to be. You can then choose which subnet to scan and proceed with pressing the “Scan” button. Once the scan is complete, expand the results to see which resources you are able to connect to for each discovered device.
6. Capsa Free
Capsa Free is a network analyzer that allows you to monitor network traffic, troubleshoot network issues and analyze packets. Features include support for over 300 network protocols (including the ability to create and customize protocols), MSN and Yahoo Messenger filters, email monitor and auto-save, and customizable reports and dashboards.
When you launch Capsa, choose the adapter you want it to bind to and click “Start” to initiate the capture process. Use the tabs in the main window to view the dashboard, a summary of the traffic statistics, the TCP/UDP conversations, as well as packet analysis.
7. Fiddler
Fiddler is a web debugging tool that captures HTTP traffic between chosen computers and the Internet. It allows you to analyze incoming and outgoing data to monitor and modify requests and responses before they hit the browser. Fiddler gives you extremely detailed information about HTTP traffic and can be used for testing the performance of your websites or security testing of your web applications (e.g. Fiddler can decrypt HTTPS traffic).
When you launch Fiddler, HTTP traffic will start to be captured automatically. To toggle traffic capturing, hit F12. You can choose which processes you wish to capture HTTP traffic for by clicking on “All Processes” in the bottom status bar, or by dragging the “Any Process” icon from the top menu bar onto an open application.
8. NetworkMiner
NetworkMiner captures network packets and then parses the data to extract files and images, helping you to reconstruct events that a user has taken on the network – it can also do this by parsing a pre-captured PCAP file. You can enter keywords which will be highlighted as network packets are being captured. NetworkMiner is classed as a Network Forensic Analysis Tool (NFAT) that can obtain information such as hostname, operating system and open ports from hosts.
In the example above, I set NetworkMiner to capture packets, opened a web browser and searched for “soccer” as a keyword on Google Images. The images displayed in the Images tab are what I saw during my browser session.
When you load NetworkMiner, choose a network adapter to bind to and hit the “Start” button to initiate the packet capture process.
9. Pandora FMS
Pandora FMS is a performance monitoring, network monitoring and availability management tool that keeps an eye on servers, applications and communications. It has an advanced event correlation system that allows you to create alerts based on events from different sources and notify administrators before an issue escalates.
When you login to the Pandora FMS Web UI, start by going to the ‘Agent detail’ and ‘Services’ node from the left hand navigation pane. From here, you can configure monitoring agents and services.
10. Zenoss Core
Zenoss Core is a powerful open source IT monitoring platform that monitors applications, servers, storage, networking and virtualization to provide availability and performance statistics. It also has a high performance event handling system and an advanced notification system.
Once you login to Zenoss Core Web UI for the first time, you are presented with a two-step wizard that asks you to create user accounts and add your first few devices / hosts to monitor. You are then taken directly to the Dashboard tab. Use the Dashboard, Events, Infrastructure, Reports and Advanced tabs to configure Zenoss Core and review reports and events that need attention.