The Network Engineer’s Guide to Making Changes

As a consultant, I have had the pleasure of working for a large number of companies in a range of industries, and one of the things that interests me in all of them is seeing the varied approaches to network changes, from the initial determination of what change needs to be made, following the change through some kind of Change Control process (in most cases), through to execution on the production network. The one thing that’s consistent with every company is that they aren’t consistent – they all have their own way of doing things, and while there’s some fundamental commonality between them, each is usually missing steps that I would consider important.

I’m not going to try to document a full change control process here (though of course, if you want to engage me to consult for your company, we can discuss that), but instead I present to you:

The Network Engineer’s Guide to Making Changes

A common sense approach to making supportable and repeatable
changes to your network.

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Musing on Cisco’s vPC (Virtual Port Channel)

Cisco Virtual Port Channels (vPC)

I was asked to explain Virtual Port Channels recently, and figured that I may as well share some thoughts about this useful technology as well as some potential pitfalls.

vPC solves problems that most people are likely to have in their network; STP recalculations and unused capacity in redundant layer 2 uplinks.

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