NMAP no ping option

 Those of you who’ve been following me the over the years, I have gone on and on about “baselining and knowing your tools “.

I have to admit that some utilities out there are very well documented, but that doesn’t mean that you do not have the opportunity to learn about how your tools behave. When there is great documentation, the process is a lot easier and I simply test and verify the options provided. Even if the documentation is correct, you will find that you will learn about your favorite tool’s options.

Every time, I use my favorite tool or utility, I use that as an opportunity to learn something. Is is even more important if the software has received an update and now behaves differently.

In this example I am looking at and NMAP’s no ping option.

At first glance it sounds like a great option, but when we start looking into it we realize that by default, a lot of things are going on that we may not want to see happening.

In this video I walk you through the option how we validate what it’s doing and how we better control the way it behaves.

Marco Polo at Work?

 I think every technician should be required to perform a simple exercise of installing equipment remotely with a non-technical person. 

Having to stop and think about all the things that could possibly go wrong, how somebody else interprets what you mean, versus what you are saying is valuable.  Not to mention you build a pretty good rapport and get a better understanding of people's technical skills with clients in remote sites.

In this video, I walk you through a true scenario where I shipped some hardware to a client along with one of my diagrams explaining what plugs into what, and things were not going well.

Enjoy

DNS Troubleshooting

 

I want to start by thanking those who reached out and provided feedback on my articles.

This article is using the new suggested format "short and to the point."

In this example, I take a look and DNS troubleshooting and use Wireshark as well as NSLOOKUP to troubleshoot a DNS issue.

In this video you will see how I used Wireshark to quickly identify that the current DNS server is having an issue and how I quickly compared it against Google’s public DNS server.

Why Should I Care About A Bootup

 

When you work with equipment that isn’t close by, you need to develop an awareness of what the various color and blinking lights mean.

For those of you who find this trivial haven’t had to walk someone through an install or troubleshooting episode from 1,000 miles away, or across town.

I encourage technicians to develop this skill since they will encounter this challenge sooner or later.

Not only should you be aware (and document) what the various color and blinking combination means, but how the lights react to various scenarios. For example, bootup, firmware update, indicator that the device can get to the internet, etc.

In this video, I show you one of many ways to measure the boot up time of a router that I was shipping out.  I’m sure you will figure your own way or doing this, if you don’t already have one.

Tip: Wireshark, setting your snaplen back to default

 

I’m always going on about learning how to use your tools properly so heres a great example of that.

For those of you who have read my articles or seen my videos about packet slicing, you probably wonder "how easy is it to set the snaplen back to its default ?"

One obvious answer is to jot down the default value and the other one is simply to type the number 1, and then press the up arrow key.

Enjoy