Views: 739This is a great question that is answered in my courses that teach L2 Ethernet, but I have never answered here. So let’s dive in. VLANs are one of the fundamental building blocks of Ethernet switching. They allow us to divide a physical switched network into multiple logical Layer 2 broadcast domains. But when
Native VLAN vs. Normal VLAN: What Is the Difference on a Cisco Switch? Read More »
Views: 3,177If you are new to Ansible, I suggest you read our article that defines Ansible, and shows you how to set up an Ansible lab environment to test and learn in. You can also read my article on real world use cases for Ansible right here. One of those use cases is Compliance Testing.
Two Ansible Network Compliance Examples Read More »
Views: 2,680Cisco had a free self paced, online learning course – until March 24th, 2025! I don’t know if it is still available – I think they are charging now. The course is called: AI Solutions on Cisco Infrastructure Essentials | DCAIE. Learn about the essentials of deploying, migrating, and operating AI solutions on Cisco data center
Want to Learn AI Networking Free? Read More »
Views: 2,497Before I provide the example, let’s be straight up about AI. Relying on AI for everything is problematic because it diminishes human critical thinking, introduces biases, and creates dependency on automation that may not always be reliable. While AI excels at processing vast amounts of data and automating tasks, it lacks intuition, ethical reasoning,
An Example of AI being used in Network Certification Training Read More »
Views: 1,907We are always adding to, and updating the technical “how to’s” contained here. When it comes to configuring a new Cisco router, much of the configuration depends on what type of router it is as well as the purpose it will serve. However, there are certain things you should configure on every new Cisco
Top 10 Cisco IOS Classic Commands Read More »
Views: 4,269Welcome to our Cisco IOS Classic Command Cheat Sheet! Cisco switches and routers use the Internetwork Operating System (IOS), which configures and controls the device’s performance and behavior. Cisco’s IOS defines an interface called the Command Line Interface (CLI), which enables administrators to enter commands into a terminal emulation program. The CLI can be
Cisco IOS Classic Command Cheat Sheet Read More »
Views: 1,905Great question! One I have received many queries on lately. Let’s get some terms out of the way first: ACI = This stands for Cisco Application Centric Infrastructure, so it is not one thing, but rather a collection of things. From the Cisco ACI web page: Cisco ACI consists of: The new Cisco Nexus 9000
How does Cisco APIC and ACI fit in the SDN world? Read More »
Views: 3,032Many of our MPLS students and colleagues ask us about VRF Lite. The common question is “Can I use VRF Lite to simplify MPLS configuration?” The answer is, that VRF Lite actually has nothing to do with MPLS nor MPLS L3VPN per se. Let’s define what VRF Lite is. A VRF is a Virtual
VRF Lite Configuration in Cisco IOS Read More »
Views: 4,119As most of us know, a key to managing the Internet is knowledge of TCP and UDP port numbers. Cisco IOS uses Access Control Lists for many purposes, but in this tip, we will focus on TCP and UDP port numbers. Port numbers are unique, well-known, registered or ephemeral numbers used by TCP (Transmission
UDP and TCP Port Number Usage in ACL’s in Cisco IOS Read More »
Views: 1,989Accessing the Internet is almost taken for granted today by most workers. They get very comfortable simply opening the lid to their laptop, turning on the wireless or connecting a cable and having access. For many of our clients, this notion of “open access” has been a continual challenge. On the one hand, visiting
Switch Port Security Usage in Cisco IOS Read More »
Views: 2,121Network broadcasts can create a huge amount of traffic on your organization’s network. When one device sends out a single broadcast, that broadcast goes to all devices on the subnet or VLAN. How can you manage these broadcasts to make your network more efficient? One method is to use Cisco Catalyst broadcast suppression —
Storm Control for Switches in Cisco IOS Read More »
Views: 2,127Welcome to our Cisco IOS Classic Interface Commands Cheat Sheet. You can see our other IOS cheat sheet here. You can view all our Cisco IOS How To’s here. Here are the most frequently used Interface commands as a quick reference/cheat sheet. This will help you remember the key interface configurations: Important show commands
Cisco IOS Classic Interface Commands Cheat Sheet Read More »
Views: 3,057The Show Environment command can be very helpful to alert you of potential hardware issues. You will need to access this command in global Exec mode. Here are the options available for the Show Environment command: show environment [alarms | all | fans | hardware | last | leds | power-supply | table |
Show Environment Command in Cisco IOS Read More »
Views: 2,948The primary purpose of the show interfaces command is for displaying the equipped interfaces and their status. Here’s the information you can get about an interface from this command: Interface type Status Speed and duplex Encapsulation Errors on the interface The last time the interface flapped The last time the error counters were reset
Show Interfaces Command in Cisco IOS Read More »
Views: 2,305What happens if there is a system or user on a VLAN that is infected by malware or is deliberately running a scanning program? What if you have some public ports on your switches that you only want to have access to the Internet and not each other? This problem can be easily solved
Protected Ports on Cisco Switches in Cisco IOS Read More »
