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Hitchhiker’s Guide to Troubleshooting IPv6

Just one of the many new “RST” sessions for CiscoLive Orlando: June 23rd-27th
Submitted by Denise Fishburne on Thu, 01/24/13 - 6:47am.

Mark your calendars! February 12th. That is when the CiscoLive Orlando session catalog goes live. And I have to say I’m stoked!! I’m stoked for you, and I’m stoked for me.

 

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Wireshark Certified Network Analyst: Taking my Wireshark Knowledge to the 'Next Level'

Wireshark is hands down, bar-none, my absolute favorite tool for network "forensics," troubleshooting, and learning. I used to think I was fairly good at it. But WOW was I living on the "tip of the iceberg!"
Submitted by Denise Fishburne on Sun, 11/25/12 - 2:36pm.

It all started a little over two years ago. I was doing my usual "Cisco Lab Rat" type job and had some customers in the room. There was a concept I was trying to explain so I did a quick sniffer capture and then used Wireshark to help me show what was actually happening "on the wire" between the two routers. Armed with my sniffer trace and the concept that "a picture is worth a thousand words," I called them over.

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Network Operational Investigating 101 (NOI-101): The Network Diagram

aka The Crime Scene Map
Submitted by Denise Fishburne on Sat, 08/25/12 - 10:06pm.

Put your detective hat on your head and your Network Operational Investigator badge on your lapel.  It’s time for another entry to the Network Operational Investigating 101 subseries (NOI-101 for short).  Today we are going to talk about Network Diagrams.  Our "Crime Scene Maps", as it were.  And if they are inaccurate… or if they are too complicated to quickly read and understand….

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Network Operational Investigating 101 (NOI-101): A new Cisco Lab Rat subseries

aka Network Troubleshooting 101
Submitted by Denise Fishburne on Mon, 07/09/12 - 9:38pm.

Put your detective hat on your head and your Network Operational Investigator badge on your lapel.  It’s time for a new subseries – Network Operational Investigating 101, NOI-101 for short.  This series will focus on the detective work (troubleshooting side) of our jobs as network engineers. 

But first… a little fun. 

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Bidirectional Forwarding Detection (BFD) – A Little About Timers

Instead of lowering and lowering IGP timers... maybe it is time to think outside the box.
Submitted by Denise Fishburne on Mon, 06/25/12 - 9:31pm.

Two weeks ago I taught Routed Fast Convergence and High Availabilty at CiscoLive US in SanDiego.  it always surprises me how few hands get raised when I ask how many people know about BFD.  With BFD OTV coming out… and BFD MPLS options already available… and support of BFD with NSF/GR on some platforms…. and BFD with SVIs..... I've decided it was time to take my knowledge to the “next level” in preparation.  And, I might as well bring y'all along for the fun.  This post and my last post are to lay some necessary BFD ground work.  

 

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Bidirectional Forwarding Detection (BFD) – A Beginning and an Introduction.......

Instead of lowering and lowering IGP timers... maybe it is time to think outside the box.
Submitted by Denise Fishburne on Fri, 06/22/12 - 11:40pm.

What is Bidirectional Forwarding Detection (BFD)? Why learn about it?  Why use it?  ..... This article is going to be a "beginning"... an "introduction" into Bidirectional Forwarding Detection.  First we will look at what it is and also look at the most "simple" use case for it that I know of.  Then we will config it on a 7600 and an Nexus 7K and watch them neighbor up.  

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Decision Making Time! - CiscoLive 2012

What classes do I want to take this year? LISP? IPv6? Multicast? FabricPath? SDN? SBA?
Submitted by Denise Fishburne on Thu, 04/19/12 - 8:04pm.

First, I have to lead off saying that I LOVE CiscoLive!!  

Yes, I work at Cisco...... Yes, I am a speaker at CiscoLive...... Yes, I'm even a Session General Manager for session groups RST (routing and switching) and IPM (multicast).   So this might all just sound like me just "drinking the kool-aid" or "marketing" CiscoLive to you.  But that is honestly not it. 

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Understanding the BGP Table Version - Part 2: More Introduction to BGP Table Version

More on BGP Table Version – the most unknown, unexplained, unloved, and unused BGP concept/value that I rarely ever troubleshoot without
Submitted by Denise Fishburne on Thu, 03/22/12 - 6:38pm.

This is the 2nd post in the 3 part series of "Understanding the BGP Table Version".  Please visit http://www.networkworld.com/community/node/80089 to review part 1.  

Last we left our network, we had the below 3 routers and a BGP table version of 4 in Router10.

 

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Understanding the BGP Table Version - Part 1: Introduction to BGP Table Version

BGP Table Version – the most unknown, unexplained, unloved, and unused BGP concept/value that I rarely ever troubleshoot without.
Submitted by Denise Fishburne on Tue, 03/20/12 - 5:47pm.

I cannot honestly imagine troubleshooting BGP without understanding the BGP table version.  I use it all the time.  Sometimes it is just a quick "eyeballing" of it to check to see if all the BGP table versions are in sync.... or if there is work to be done.  I see people "eyeballing" the up/down time for a BGP peer when they are troubleshooting.  And sometimes I see them quickly eyeball the InQ/OutQ columns.  But I rarely ever see anyone using the BGP table version.

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Prepping for the CCDE Practical

One needs design “experience”, “exposure”, “breadth and depth”
Submitted by Denise Fishburne on Sun, 01/22/12 - 4:32pm.

Ever since I passed my CCDE, I get emails from random people, some I know and some I don't know.  The wording can be different, but the essence of the email is always the same - 

"How does one study for the CCDE"? 

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Making My Amends

A Lab Rat apologizes for dropping off the face of the earth and not posting. ☺
Submitted by Denise Fishburne on Fri, 01/20/12 - 2:03pm.
"Uh ... Err ... Hi again. It's me. So ... uh ... how's it going? What have you been up to? Err ... umm ..."

Ever had one of those times in your life that you just don't know what to say to a friend? You told them you would do something (call, write, return a call, keep in touch, call more often) but you don’t.  And then time passes.  And you think to yourself… "Man, I have to fix this."  But you don't.  And more time passes.  Now it is just awkward!

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The Cure for Network Downtime is Not Just Technology

Design and tune your network all you want. But if your company doesn’t also have a culture of high availability, your High Availability and Fast Convergence is not complete.
Submitted by Denise Fishburne on Tue, 08/16/11 - 7:21am.

You just came back from CiscoLive and went to some classes (maybe even some of mine) and now you want to run home and start figuring out the alphabet soup of choices and decisions that is High Availability (HA) and Fast Convergence (FC) - NSR, NSF, GR, BFD, SSO... (the acronyms go on and on)

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I’ve got a new MPLS lab. Tell me how to play with it

What do you get a Lab Rat that already has everything? Give her WAN lab equipment and tell her she has a side project to build whatever she wants with it!
Submitted by Denise Fishburne on Fri, 07/29/11 - 2:36pm.

I’ve just had Christmas in July.  I’ve been given a whole list of lab equipment, so big that naming all the SIPs, SPAs, and line cards, would end up blowing my word count limit for one blog.  So I’ll just keep it at a high level.

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