Latest Posts

Easy to remember subnetting trick

01 Mar 2019

If you are related to the world of networking, you would of course have had to subnet at some point of your career. Though it is rare that you may have to do it without the help of the internet, I am willing to bet that at least most you would have had to do this at least once ( maybe in an interview? ).

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Introduction to CoreDNS in a Dockerised environment

23 Feb 2019

CoreDNS is a relatively new DNS server written in Go. CoreDNS was written keeping in mind the evolving needs of today and the ability to work well with cloud native applications. In Kubernetes 1.13, CoreDNS is the default cluster DNS server.

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Reverse SSH Tunnel

20 Feb 2019

I have a raspberry pi running at home taking care of some home networking/automation stuff. I may at times find myself in a need to log into the Pi while not at home to check up on things. Without a dedicated public IP address this often proved a difficult task. Earlier I was using an ngrok tunnel for this. Read more about ngrok here. The problem with this was that ngrok would give me a different URL every time the Pi reboots. To get around this, I was using a system where I would send an email to a gmail account set up specifically for the Pi and the Pi would respond back with the ngrok URL. I will write a post about this later and link it here. Since I ran into some issues with this, I decided to go a different route which this article is about.

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DNSSEC Keys and Signing Explained

19 Feb 2019

This article describes what happens when a zone is signed with DNSSEC. This document helps to understand the concept of zone signing and does not detail the actual steps for signing a zone.

Note: I have taken some liberties with this article in the interest of simplicity. For full and accurate information, refer DNSSEC RFCs. NXDOMAIN validation is not included in this article.

Let’s consider an unsigned zone test.com. Below is a representation of the zone file with sample records with only the relevant fields.

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