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Thoughts on network engineering from Jeff McLaughlin

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July 9, 2015

TAC Tales #4: Airline Outage

I don’t advertise this blog so I’m always amazed that people even find it. I figured the least-read articles on this blog were my “TAC Tales,” but someone recently commented that they wanted to see more… Well, I’m happy to oblige. The recent events at United reminded me of a case where operations were down […]

TAC TalesTagged Cat 6500, EIGRP, TAC, united airlines outage4 Comments on TAC Tales #4: Airline Outage
April 17, 2015April 17, 2015

Hub and Spoke with BGP

In my previous post, we saw the theory behind hub-and-spoke VPN. We saw how H/S involves multiple VRFs with cross-importation between them, and we traced the basic flow of a route advertised from one spoke to another. Next, we are going to look at two options for configuring H/S VPNs. In this post, I will […]

JNCIE, Junos, RoutingTagged hub and spoke, mpls, vpn14 Comments on Hub and Spoke with BGP
December 31, 2014

Hub and Spoke VPN Part 1

One of the JNCIE-SP exam objectives I found difficult was hub and spoke VPN. Conceptually it’s not easy, and as is often the case, the documentation is only somewhat helpful. This series of posts is designed to walk you through the concepts of hub and spoke VPN, as well as its basic configuration using BGP, […]

JNCIE, Junos, RoutingTagged hub and spoke vpn, layer 3, mpls5 Comments on Hub and Spoke VPN Part 1
December 10, 2014December 10, 2014

The joy of being an “expert”

Ah, the joys of being an “expert.”  I had forgotten what happens after you pass an exam like the JNCIE.  One of my colleagues starts grilling me on various topics for which I am unprepared, since they weren’t covered on the exam.  MX architecture, MC-LAG, MX virtual chassis, etc.  Be careful what you wish for. […]

Uncategorized1 Comment on The joy of being an “expert”
December 9, 2014February 5, 2016

TAC Tales #3: GSR

Shortly after I went to work at TAC, my first team, which was dedicated to enterprise customers, was dissolved, and I ended up on the Routing Protocols team.  The RP team supported both enterprise and service provider customers, and I had zero experience on the SP side.  There was quite a learning curve ahead. One […]

TAC TalesLeave a Comment on TAC Tales #3: GSR
December 9, 2014December 11, 2014

JNCIE-SP Experience

This is a follow-up to my previous post on the JNCIE-SP exam. Some thoughts about the experience of taking the JNCIE exam, especially versus Cisco:

JNCIETagged jncie-sp4 Comments on JNCIE-SP Experience
December 5, 2014December 5, 2014

Passed JNCIE-SP: Initial Thoughts

Back to the blog, now that the JNCIE-SP is finished. I got #2332. The last time I did an expert-level exam was 2008, and I forgot just how challenging it is. I passed my JNCIP in June and it took me until November, working solidly most of the time, to get my number. It’s been […]

JNCIETagged ccie, jncie-sp, juniper2 Comments on Passed JNCIE-SP: Initial Thoughts
September 17, 2014

Blogging on hold

For the handful of people who come across this blog and have posted comments, thank you very much for the kind words. This blog is on hold for a bit while I finish up my JNCIE-SP, which I am taking in a couple weeks. I’ve come across a lot of excellent blog post topics from […]

Uncategorized3 Comments on Blogging on hold
April 25, 2014September 28, 2021

TAC Tales #2: How to troubleshoot

The case came in P1, and I knew it would be a bad one. One thing you learn as a TAC engineer is that P1 cases are often the easiest. A router is down, send an RMA. But I knew this P1 would be tough because it had been requeued three times. The last engineer […]

TAC TalesTagged aaa, HTTS, mlppp, ppp, TAC, troubleshooting4 Comments on TAC Tales #2: How to troubleshoot
April 10, 2014April 25, 2018

RIB Group Confusion

This article continues to be the most popular one on this blog.  However, I published it back in 2014 while I was working on my JNCIE-SP, and that was a long time ago.  I now work at Cisco and do not have access to Junos, and my memory of Junos is getting spotty.  I am […]

Junos, RoutingTagged inet.2, inet.3, mpls, rib-groups, routing, vrfs42 Comments on RIB Group Confusion

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