Automate the configuration backups of all your network switches/routers

This is a quick and easy way to ensure that the configuration on all your switches/routers are securely and reliably backed up. All you need is a Linux machine that can reach all your intended devices over the network. Once this is setup, you can have the configs automatically backed up once every week or day or every hour, if you so choose. In other words, “Set it and forget it”.

I promise this going to be easy and will be setup in a matter of a few minutes.
Read more

New Switch Setup Guidelines

In this article, I have come up with a step-by-step approach to setting up a new network switch (either in a data center or campus). Think of it more like a concise checklist or a set of guidelines, which can come in handy and save time performing a repetitive task, for instance configuring a switch. The example that I have used is that of a simple layer-2 Arista switch. However, it could a switch from any vendor, as the concepts remain the same, despite a different CLI. I will write another blog post about accomplishing the same objective in an automated/templatized manner in the near future.
Read more

Generate a mapping of IP addresses to hostnames and vice-versa in seconds!

As network engineers, most of us have encountered a situation like the one I have described. This is a conversation with an Application guy (let’s call him Bob):

Me: Hey Bob, we are moving Vlan 331 of your SAP application next week and all those servers will be impacted.
Bob: Ok. Which all servers are a part of this Vlan thing?

Me: Well, they are app servers. Shouldn’t you be knowing all your servers?
Bob: Duh! I know my applications, man. Don’t ask me about servers and stuff. You folks manage that.

Read more

View the ‘show’ output from multiple devices using Python

Traditionally, us Network Engineers have had to live at the mercy of the command line for performing pretty much any task in our day-to-day work lives. Let’s say for example, that you want to verify the routing table of a couple routers. Conventional wisdom tells us that to accomplish that, we need to login to each router over SSH using a terminal emulator like Putty and type ‘show ip route’.  Easy stuff! What if, instead of a couple routers, you have to do that on 10 routers… or how about a 100?  You are likely to spend the next couple hours doing just that… login, check output, repeat!

Well, turns out that there is a much easier way to get that accomplished.

Read more

How we upgraded the entire Network Infrastructure in 2 weeks

I work as a Network Engineer at a Research Center in Silicon Valley. Being the only ‘network guy’ here, I’m responsible for the management of all networking devices like Routers, Switches, Firewalls, Radius Servers, VPNs, Wireless controllers, Linux servers,  etc, etc…

For a couple years, we have been trying to replace our ageing and end-of-life Cisco 6500 series switches. However, due to budgeting issues, the project kept getting punted to the new quarter or year. One fine day, in the 1st week of December 2014, the CFO tells my manager that we have the budget now. But there is a catch! It has to be completed by the end of the year. Yes, a whole rip and replace of about 3000 network ports in less than a month!

Read more