Free Network Troubleshooting Tools

Table of Contents

Tools for Network Engineers

We’ve built a list of some great free and very useful network troubleshooting tools, scanners, and sniffers that all network engineers need to have in their tool kit.  This list is by far not inclusive.  If you know of a great tool that you use and would like to see it listed here, let us know.  Leave a comment below and we’ll post a link to it!

Network Scanning Tools

These tools are great for scanning and sniffing network packets on your network.

  • IPScan – also known as Angry IP – is a great scan tool for seeing what ip addresses are in use on a given segment:
    • Wireshark – previously known as Ethereal has been the defacto standard in free network sniffer applications. Must have for any network engineer

IP Address Tools

  • WildPackets makes a nice IP calculator that is free and very easy to use. You do have to sign up to their website to download the tool.


Free Online Network Troubleshooting Tools

There are a lot of online tools that are available that can help you “see” you network from the outside and get a good idea of any issues that you may be unaware of.

Network Tools Web Site

ZoneEdit Web Based NSLOOKUP



UNIX/LINUX Tools for Windows

Sometimes, for many Windows users, having access to Unix command line tools is so helpful. This little package is great to have if you know or love Unix/Linux

  • Unzip this file to the root of your hard drive and add the location to your path to get all the famliar unix like commands on from the command prompt:


Upload Tools – TFTP-FTP

You will always find yourself in a situation where you need to transfer a file. Here are some common tools to get the job done.

  • A good tftp application is a must have if you even need to upload a large IOS to a router. tftpd32 is a good all around tftp server – tftpd32 works well for most situations:
  • FileZille – Great free FTP client


Router Simulators

If you ever want to test out a new config or work on your networking skills but don’t have access to a router or a lab, router simulators allow you to simulate a Cisco or Juniper router, firewall or switch right on your desktop.


Free Router  and Security Software

There are some great free router software that is available that you can load on a dedicated server or VM that performs just as good a job if not better than a standard Cisco device!

Do you know of a cool tool to add to the list? Let us know, leave a comment below. Let us know about a tool you use and how you use it. We’ll add your suggestion to the list!!!

5/5 - (1 vote)



Senior Network Engineer, technology enthusiast, guitar and bass player. Joe Wilson is the creator of as well as other niche websites that can be found around on the Internets.

What do you think about this article?


  1. If you prefer a suite of tools that take on multiple roles, NetCrunch Tools can replace several other downloads. having twelve tools all in one attractive package is a smart idea, even if you don’t use each one of them.

  2. This is a nice video. It is simple, yet helps us rlzieae things we might miss.Currently, I am 12 years old, waiting until I finally am able to take CCNA at 13. I have been studying for a while now, but this video made me rlzieae that I had to work harder and not be so relaxed

  3. The one I use everyday is called Pinkie. It does ping, traceroute, dns, bulk dns, ip subnet calculator, pingsweep, portscan and tftp.

  4. Hi, Above tools are very important for the person who are interested in networking…I'm currently working with BOSON simulator software. which will helps to configure routers and switches…..So I suggest BOSON simulator which will help the people who are willing to do CCNA and CCNP…..Thanks for sharing



    • Hi Naresh,
      I agree. Boson does make a very good simulator. The one thin I do not like about Boson is that is it a bit expensive. Especially when you compare it to GNS3. GNS3 is an open source free virtual router emulator for Cisco routers switches, pix and asa firewalls as well as Juniper routers. GNS3 does have its draw backs too. You will need a copy of a supported router IOS in order for it to function.

      Thanks for the recommendation!

      • Hi

        could you plz tell me how to use juniper router in GNS3 and it would have been better if you would send me the deatils step.

        • Hi Sam,
          I have to be honest I have never setup Juniper on GNS3. I would love the opportunity to play with it but I dont have access to JunOS. I can't imagine it being much different than getting Cisco to run. You might want to check the GNS3 forums too and see what their experiences are.

          Let me know how things turn out!

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