In the wake of microservices, it's hard to maintain how services communicate with each other. Microservices maintain config files to know how to talk to other services. This is an error prone approach as config file is maintained by humans. The most common solutions

Self reference. Use case was to update a configfile (datadog) in all currently running instances..And restart the process. - hosts: all tasks: - name: line insert lineinfile: path: /etc/datadog-agent/datadog.yaml insertafter: 'collect_ec2_tags: false' line: 'collect_ec2_tags: true' notify:

What're terraform modules? Module is an abstraction for multiple resources which can be reused. Let's say we define our website service with the following layers in AWS: s3 for static resources (html, css, js, images, etc.) cloudfront for cdn application load balancer for receiving

Note: Intended for self reference. We've to delete clients/nodes from chef when an ec2 instance terminates. We've followed the pattern of using instance id as chef node id. And the following script helps to delete nodes that are terminated. The script runs every

Scenario: Mono-repo with multiple projects hosted on github.. We need a CI/CD setup for this, whenever a pull request is raised. Inputs: Code hosted on Github Continuous Integration/CI server: CI server shall merge incoming branch into master in its environment, when a

An ongoing document on terraform clean practices I follow. Type 1: Ingress defined inside the same resource as security group. resource "aws_security_group" "sample-sg" { name = "sample-sg" vpc_id = "${aws_vpc.default.id}" ingress { protocol = "

Due to various reasons, mongodb secondary goes out of sync and might be dead/stuck in recovered state or replication lag grows beyond acceptable limit. InstructionsMake sure primary is up and running. Login to primary mongo, let’s say calendar-mongo-rs-1-1.Check acceptable mongodb replication

The metaphor is quite common in cloud for servers. Gist: We name pets and take care of them, nurse them. We ensure pets are in healthy state always and attend immediately if otherwise. We number cattle. When one gets ill, we shoot them. We

In a typical setup, we need a resilient way to track down the errors. To think of it, we're writing code and we're generating the error. Thus, we should know it even before a user reports. While tracking logical errors might be a technical

I want to launch mongodb sharded cluster with chef and terraform on AWS.. show me steps! Let's name our mongos cluster as "Roads". Assumptions: There's a private VPC in AWS with subnets in multiple AZs. There's a bastion host launched in same

Here's a quick guide on how to upgrade mongodb version on a sharded cluster hosted on AWS, AmazonLinux OS. This is done, manually, on a cluster with ~30 TB data with minimal downtime (less than a minute). Mongodb components: mongos: Server responsible for routing

Meant for self reference. This is a gist of launching an RDS mysql instance with terraform. It uses module from here: https://github.com/terraform-aws-modules/terraform-aws-rds resource "aws_security_group" "sample-mysql" { name = "sample-mysql" description = "Allows services to

Down to dirty blog on setting up VPC with terraform. This is to setup a new VPC in ap-south-1 with three public and three private subnets. It'll also take care of NAT Gateways, Internet Gateways, etc. What the script does/creates: There is 1

Assumption: You've a kubernetes cluster running on EKS, and all the kubeconfig, kubectl, aws authentication are handled. What's EFK? Elasticsearch: A search database with support for REST api queries. Fluentd: Data collector typically used for collecting logs in a unified manner. Kibana: Visualisation tool

This is for self reference. You may find it useful too. Objective is to deploy a kafka + zookeeper cluster in a dirty way. This is going to be on AWS. Assumes you can launch an ec2 instance with latest amazonlinux AMI. Quick intro of