routing

BGP Default Route Failover Using Reachability

Sometimes political, financial, or logistical hurdles determine how we solve networking problems. In these tricky situations we may not be able to solve the problem the way we’d prefer, but we still need to solve the problem.

In this post I’m going to look at how we can solve a WAN failover scenario¬†when we have a default route learned from both of our service providers and a reachability problem via our primary ISP.

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Amazon S3 Outage: We’ve All Been There

I’ve been thinking a little bit about the Amazon S3 incident. Not really the incident, actually, but the responses to it. More than once I read something along the lines of “I’m sure that guy got fired” with regard to the engineer who entered the fatal command.

Sure, that’s kind of funny for a quick tweet or in the greater context of a blog post on change control, but for me, I’m not sitting at my desk shaking my head right now. Instead, I’m reminded about the times I did the exact same thing (on a much smaller scale) and will probably do it again.

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How Do You Know That’s True?

About a thousand years ago, rather than configure routers, I taught high school English.

One day, instead of unpacking our favorite Shakespearean sonnet, I was sidetracked by a student who asked me how we know anything about electrons and how they orbit the nucleus of an atom. Apparently he asked his physics teacher the period before and got a pithy “electrons are the essence of a negativity.”

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Network Automation: Another Tool in the Toolbox

Over the last few weeks I’ve noticed a few tweets and blog posts regarding the immaturity of network automation methods and the danger in utilizing those methods in production networks. Though I agree that processes always have room to mature and that wiggling wires in a production environment always poses some risk, I believe this new emerging narrative in social media makes several assumptions that aren’t necessarily true.

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Routing at the Access Layer

Network devices have become so powerful that concern over hardware resources have all but disappeared. Modern routers, switches and firewalls can handle much more than their predecessors, and network designs are changing as a result. Network designs are shifting from the classic three-tiered model of a switched access layer and routed distribution and core layers to a completely routed design. Read the rest of the article at TechTarget’s SearchNetworking site.

 

SD-WAN with Silver Peak: The Business Use Case

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Amidst discussion of SDN ambiguity at Networking Field Day 11, SD-WAN stood apart as something we understood, and I think that’s because we understood its use case very well.

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