Ease is bigger threat to progress than hardship
In our day-to-day life, we take a lot of things for granted: our body, food, friends, family, internet, domain name (URL) of facebook, IP address of instagram, etc. In our ignorance, we forget to consider how much their absence would affect us, the hardship and inconvenience we’d face, if, one day, any of these just …
Continue reading “How DHCP and DNS are managed in AWS VPC – Part 1”
Recently I was asked to set up a CI- Pipeline for a Spring based application.I said “piece of cake”, as I have already worked on jenkins pipeline, and knew about maven so that won’t be a problem. But there was a hitch, “pipeline of Gitlab CI“. I said “no problem, I’ll learn about it” with …
Ansible Variables and Variables Precedence What is a variable? A variable is reference to data stored in a computer program. How to define variable in Ansible? Variables Defined in Inventory Variables can be defined in inventory in two ways – 1. Host variables [web]host1 http_port=80host2 http_port=443 2. Group variables [web]host1host2[web:vars]http_port=80proxy=proxy.example.com Variables Defined in a Playbook …
Continue reading “Ansible Variables and Variables Precedence”
Overview First of all I would like to give credit to Docker which motivated me to write this blog, I’ve been using docker for more then 6 months but I always wondered how things are happening behind the scene. So I started in depth learning of Docker and here I am talking about Namespace which …
Overview Before talking about forward proxy and reverse proxy let’s talk about what is the meaning of proxy.Basically proxy means someone or something is acting on behalf of someone.In the technical realm, we are talking about one server is acting behalf of the other servers. In this blog, we will talk about web proxies. So …
Overview Prometheus is an opensource monitoring solution that gathers time series based numerical data. It is a project which was started by Google’s ex-employees at SoundCloud. To monitor your services and infra with Prometheus your service needs to expose an endpoint in the form of port or URL. For example:- {{localhost:9090}}. The endpoint is an HTTP …
When ssh: connect to host ip_address port 22 Connection refused Unable to access server??? Exactly when you see the error – “ssh: connect to host ip_address port 22: Connection refused” while connecting your AWS EC2 Instance. In order to find solution of the problem, you will go to AWS forum and other channels where you need to …
Introduction A few days back I encountered with a simple but painful issue. I am using ELK to parse my application logs and generate some meaningful views. Here I met with an issue which is, logstash inserts my logs into elasticsearch as per the current timestamp, instead of the actual time of log generation. This …
Introduction : As we had a discussion about Ip addresses and their classes in the previous blog,we can now start with Sub-netting. Network Mask /Subnet Mask – As mask means to cover something, IP Address is made up of two components, One is the network address and the other is the host address.The Ip Address …
Continue reading “Classless Inter Domain Routing Made Easy (Cont..)”
Introduction : One day I was working with VPC (Virtual Private Cloud) inside AWS(Amazon Web Services), where I had a need to calculate the CIDR notation of an IP address and subnet combinations. I had to use online tools to calculate the Subnets and CIDR every time when I was working with VPC, but I …
Devops Done Right 