An IoT experiment to create a gas based suppression system that can be used to extinguish fires inside water sensitive enclosures such as data centers. We make use of Arduino microcontrollers and several sensors to create this system.
A major part of your AWS bills comes from EC2 uptime and EBS storage use. In order to save on these costs, it is recommended to stop your instances whenever it is not required. Often times, your Development, Test or UAT environments aren’t used by developers during off-hours. Thus this would be a great time frame to temporarily stop the instances and save up on costs.
In order to do this, we can make use of AWS Lambda, which lets you run your code or without setting up any servers. Since it charges based on the compute time taken up by the code, it is very cost efficient. A task running twice within a 24-hour cycle for typically less than 60 seconds with memory consumption up to 128MB (like the script in this post) typically costs around $0.008 per month.
We will use the official AWS SDK for Python, boto3 to write our script and then run it using Lambda functions.
Default Read Replicas provided by AWS are instances which should be of the same instance type as the master DB or higher. This might not always be an ideal solution since read replica servers do not require significant computing power. As an alternative, one can create a read replica on a standalone EC2 instance or a RDS DB instance. In the following scenario, we’ll create a read replica running on MySQL syncing with a master DB running on Amazon Aurora. The replica instance type can be any type as seen fit by the user.
Docker is a container technology that provides a layer of abstraction on the OS that it is installed on(Linux or Windows). It allows the packaging of a software application into a image which consists of everything the software requires to run: code, system utilities, third party libraries and other dependencies. Then this image is run on the common layer of abstraction defined above. Therefore, it becomes easy to move and deploy the software application (which refers to the container) across any infrastructure or environment.
Updated: August, 2018
This Ansible playbook should give an idea about the configuration management capabilities of Ansible. It sets up a group of Tomcat nodes which are load-balanced by Apache using the Mod-jk module. In addition to this, it also sets up all other dependencies and also configures the installed services to run on startup.