Author: Josh O'Brien

What did you Expect? Part 3, Fixing Stuff and Scaling Out.

When you setup to learn new things you are bound to get a bit sideways once and awhile.  With writing code I think that is even more the case.  You start out with an idea and if your lucky like I have been so far it starts to flow and things just work.  But in the spirit of learning in manageable chunks and sharing the experience with you I started targeting a single host.  When I tried to make the leap to multiple hosts things got interesting.  Along with that it became clear that these posts were going to get messy quick.  So lets clean all that up and move on to the cool stuff. Read more

Setup GNS3 Automation Network in OSX

I have been working to learn how to use Python to automate interactions with network devices.  Due to what I have in my lab and the fact that we have GNS to model Cisco Networks I started with IOS.  In order to really test out the automation scripts I have been building, I felt it was necessary to run them against at least ten devices to make sure they would scale out and recover well from errors.  In order to do that I had to build out a 10 device lab.  This is how I did it. Read more

NAT Store: The books you read and the stuff you use.

One of the lines that I have taken to heart in Life is  “your only difference between now and ten years from now will be the books you read and the people you meet”.  I read it years ago and since then I have doubled down on my reading.  Prior to this I was reading lots of fiction and technical documents around doing my jobs as a network engineer.  Since then I have expanded into Finance, Marketing, Strategy and more.  I can’t begin to tell you the difference in my life it made.  While I won’t go into details actions I took as a direct result of what I was reading helped me go from a mid five figure salary to a solid six figure salary and on a pace that made me part of the businesses I was with not just an employee. Read more

What did you Expect? Part 2: Working with VLANS

So we started off in Part 1 breaking down what a basic SSH connection and authentication looks like using Python and Expect.  To add some context to this I am using the pexpect library for Python.  This library falls back on system level tools like the the SSH client inside OSX or Linux.  I can’t speak to how this works with Windows so just be aware of that as we move forward.  In the long term I will start adding more complexity such as the ParaMiko and NetMiko libraries that use integrated SSH clients but for now I want to keep this as simple as possible so both you and I can get the most value out of these posts. Read more