Many times I have found it needful to be able to find what adapters are loaded on a server, whether they are not showing up in device manager, I wanted to validate whether network teaming was enabled, I wanted to see if some firewall miniport driver was installed, I wanted to see if the local Antivirus added anything, or any other reason. Here are some steps I have found helpful when validating what Networ... [More]

FtBP: End-to-End, B-to-A Part 8/8                   Last time we talked about how a network packet changes through a NAT device, and we finished off the transit of our network packet to Computer B. Today we will follow a network packet from Computer B back to Computer A. Here is the Diagram we will work with:                   ... [More]

FtBP: Switching Part 3/8                   In our last discussion we covered the formation of a network packet in preparation to send that packet on the wire. Today we will cover the packet's travel through its local VLAN from Client to Server. Let's start by reviewing what we had in our network packet from last time. Here is where we left off:           &nb... [More]

FtBP: Packet Formation Part 2/8 Packets on the wire (purposely repeated)                 As we go through this series we will go over some examples to help understand the progression of a network packet throughout a network segment. We will start off simple and grow to more and more complicated packet transfers, but before we get to the wire we will need to look at how the data is packaged, and so how the packet fo... [More]

  FtBP: Prerequisites Part 1/8                   One understanding that I think has helped me a great deal in troubleshooting problems, and designing networks and services is the evolution of a network packet as it transverses different pieces of network hardware. Today I will try to cover at a high level, the packet creation process, switching to the local Vlan, packet routing, NATing and firewalls, a... [More]

Have you ever noticed that ping and nslookup give different results when resolving a name? This happened to me many, many times and it caused me some frustration before I made the effort to understand why it was okay for the results to be different. Let's look at some of the reasons that nslookup results can be so different from ping results. There are really three important things to understand I think: How the Windows client resolver works (at least at a high level). What ping is intende... [More]

I honestly believe that one of the greatest barriers to proficiency for IT administrators is terminology.  There is such a variety of terms, acronyms, and usages, that IT is really like its own language.  The good news for those of you that speak it, you are now fluent in at least two languages.  For those of you working your way in, remember to roll your ‘R’ – and good luck with the lingo. While we are still working on getting a common understanding between us,... [More]