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Summary: Use Rate-Limiting to Alleviate Link Saturation

Here’s the scenario: you have a remote branch office in Miami that has been running smoothly for months. Today you are getting complaints from the site that relate to phone calls dropping, email and network connectivity being intermittent. Management is pushing your team to get it fixed.

You start by looking closely at the WAN circuit going into the site. You use a program that Cisco introduced called NetFlow. By using this program you are able to determine that the WAN link is being saturated by a particular server to server file transfer. You need a quick fix to this issue. You could go with QoS but that could take some time and input from the site to gather statistics on the critical traffic. Instead you decide to utilize Rate-Limiting on the WAN interface.

Tags: #CiscoChampion, #CiscoEnterprise, #NetworkEngineer

Read the full article here.


Defending Your Console

A new problem has arisen in CCNA class: We have a lab that asks the students to enable a debug command; the debug overruns the console buffer to the extent that commands cannot be entered, and this goes on for more than an hour!

In my 15 years of teaching CCNA classes, we have always taught the dangers of using debug commands on production equipment. To demonstrate this, we would have the students run the debug ip packet command, let it run for 30 seconds, and then turn it off. Of course, turning off the debug is challenging, so we would teach the trick of turning the debug off before we would turn it on: adding the undebug all command to our command history buffer.

Running this test on the 2500 series and 2600 series routers would usually cause a crash and a forced reboot. After we changed the lab equipment to the newer ISR 2800 series, the same demonstration no longer resulted in a router crash; however, it introduced a new problem: loss of control of the command line.

The sheer amount of debug messages would cause the command line to be unusable. The debug messages continued to overrun the console buffer for over an hour before we would finally run out of patience and power cycle the router. In a lab scenario, this causes the students to take an excessive amount of time to finish their lab, and for people studying for certifications, it wastes precious study time. A better way to manage debugs is needed. We would like to see the debug messages (they can be very helpful in both troubleshooting and understanding how protocols function), but we would also like to retain control of the command line. Read More »

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Introduction to Nexus 1000v Features and Deployment

Over the last 12 months I’ve been doing a lot of work that has involved the Cisco Nexus 1000v, and during this time I came to realise that there wasn’t a huge amount of recent information available online about it.

Because of this I’m going to put together a short post covering what the 1000v is, and a few points around it’s deployment.

What is the Nexus 1000v?

The blurb on the VMware website defines the 1000v as “..a software switch implementation that provides an extensible architectural platform for virtual machines and cloud networking.”, and the Cisco website says, “This switch: Extends the network edge to the hypervisor and virtual machines, is built to scale for cloud networks, forms the foundation of virtual network overlays for the Cisco Open Network Environment and Software Defined Networking (SDN)”

So that’s all fine and good, but what does this mean for us? Well, the 1000v is a software only switch that sits inside the ESXi (and KVM or Hyper-V, if they’re your poison) Hypervisor that leverages VMware’s built-in Distributed vSwitch functionality.

1000v Read More »

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5 Steps to Make Mentoring your New Years Resolution

When people think of mentoring, the images of an apprentice learning from his master are often rendered. The senior blacksmith guiding his pupil through the craft he has spent his life perfecting. Over the years mentoring has changed, and today it is used throughout business to guide the greenhorns throughout their craft, or even life. But the idea that this advice must come from a wise old sage is a bit passé.In today’s world, the 1:1 ratio of mentor to apprentice isn’t common place. While you will still find these relationships around the world, the world has changed, and technology has helped us evolve. As a matter of fact, I believe the Cisco Champions program is fundamentally a group of mentors. We are all selected because we participate in social media, we blog, we have a sense of community. Because of all of these things, I believe many of us are already indirectly mentoring the community as a whole. But I wanted to mainly focus here on the local mentoring you do in your daily work life.

  1. Listen – In any relationship the power of listening is massive, just ask a therapist what their number one tool is. When you take the time to listen, you are showing support and encouragement. Once you have taken the time to listen and understand, the advice you provide will be much more valuable.
  2. Never stop learning – A career in IT means that you can never stop learning, lest your skills become antiquated. This just doesn’t mean you should keep up on the industry changes, or take a class on some new technology every year. I believe that it’s important for everyone to have their own mentor(s). It’s not always just about the technology, but sometimes the methodologies, and strategies that we can learn from our peers are much more important.
  3. Be committed – Being a mentor is a commitment, it certainly takes time and effort, but it is an investment! You spend your time and energy into your pupils, but you end up getting much more out of the experience. Be sincere, and interested in their development. Remember that your fledgling is easily demotivated by your indifference towards their development.
  4. Be open-minded – Some folks say that the best way to truly learn a subject is to teach it to others. Teaching is rewarding in that you get to not only review the subject matter for yourself, but you get to answer questions you may of never thought of. Also remember to listen, as some folks will never see your side of a discussion unless they’re convinced that you’ve understood theirs.
  5. Blog – And participate in social media, because sharing information is important. It is easier today than ever to share knowledge and incite discussion amongst the community of your peers. And because of that, it is easier than ever to reach out for help and guidance. So remember, when someone does, be a mentor. Listen, Understand, and most of all, try to help!

There are 5 ways you can become a (better) mentor. But I imagine many of you are asking why… Mentoring isn’t just about taking care of a junior staff member, it’s great for you in many different ways. First of all, helping others provides a wonderful feeling. Especially when you’re able to help make a difference in their lives! In addition, teaching is a wonderful tool that not only helps educate the student, but also forces you to continue your own learning to stay ahead with your advice.

I hope this has convinced some of you to step up your mentoring game in 2015. I certainly hope to spend more time at a white board this year myself.

Read More »

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Summary: 2014 – Year of the Internet of Things (IoT)

A lot happened in IoT in 2014. About this time last year, John Chambers laid out $1.9T market projection for IoT at CES and that drew significant attention and generated momentum in many industries. Over the year, we saw some real world use cases and innovative companies and technologies at the IoT World Forum in Chicago.  IoT really gained traction across many verticals over the year. While a lot of progress has been made, IoT is still evolving and globally companies and industries are still trying to figure out business models, technology selections and IoT standards. Cisco has led the way on many IoT fronts in 2014 and our own IoT Cisco Champion Pranay Prakash scopes the year and defines it as the Year of the Internet of Things and outlines what’s in store in future.

Read my full LinkedIn article here.

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