Tom Ammon despatched me his ideas on deciding on the correct stage of abstraction in your network automation answer as a reaction to my What Is Intent-Primarily based Networking blog article, and permitted me to publish them on ipspace.web.

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I entirely concur with your what vs how instance with OSPF. I do the job on a NOS team exactly where if we wished, we could say, in its place of “run OSPF on these links”, do this:

• Send out hi messages on these hyperlinks
• Detect neighbors
• Changeover by the neighbor states
• Kind adjacencies
• Compute greatest paths.

But, we would hardly ever do that. To do that at even medium scale would make the deployed network significantly fragile as you add nodes, and it is just plain a whole lot of do the job – toil that returns no discernible operational gain.

To me this is pretty a lot like the distinction among declarative and very important strategies. You continue to have to have vital logic at some level as you in the vicinity of the bottom of the stack (you just cannot just say to a CPU sign-up “hey, give me the very best path between A and Z!”) but you get a ton of nice gains by developing issues in this kind of a way that you can believe in and relatively ignore the decrease layers of the tech stack as you set your human focus on the stuff larger up.

Recently, I have been thinking about automation (at the very least, the configuration management portion of automation) additional in terms of layers of abstraction, and one’s functioning position in those levels. I consider the conclusion I am coming to is this: You really should operate your network at the highest layer of abstraction feasible that will enable you to hit your trustworthiness, availability, and other business enterprise targets.

It can take $(effort) to automate (and preserve!) a option to autoprovision branch routers/switches/SD-WAN appliances, configure suitable BGP friends, configure endpoint ports, and many others.. It requires $(effort and hard work)+N to construct orchestration that will let you say “build me a branch business office employing the usual pattern”. But it must be a conscious option and I assume proactively selecting the layer of abstraction you want to perform at can be really empowering. It is genuinely just a matter of how superior an abstraction you want to journey (and crash) on.