AWX on AWS with CDK (in Typescript)

Ansible Tower and AWX We have used open-source Ansible extensively in the past. While the automation is convenient, the lack of UI makes it not as suitable as a team collaboration tool. One way to allow team collaboration with open-source Ansible, is to use Jenkins to glue the components together, as discussed in the Automated … Read moreAWX on AWS with CDK (in Typescript)

Deployment of a medical imaging web service

[Update] Some security improvement was introduced in may 2021. Here‘s detail. In this project we introduce a medical imaging web service based on Orthanc, an open-source project of DICOM server, and a pipeline to deploy such server automatically and consistently. This little project involves a number of technical deets in DevOps, to deliver a web … Read moreDeployment of a medical imaging web service

AWS Certified DevOps Engineer Exam Tips

The last 30 days have been exhausting for me. I studied hard on the new AWS Certified DevOps Engineer exam and thank goodness I passed (750 out of 1000 is required). This was the hardest professional certification I ever worked on. The exam was re-launched recently in March 2019 so there is still a shortage … Read moreAWS Certified DevOps Engineer Exam Tips

SSH key pair for access between instances in CloudFormation

We use CloudFormation to deploy infrastructure including private and public subnets, as well as EC2 instances. It is a good practice to place as many instances as possible in private subnet and access those only from Bastion Host in the public subnet. For smaller systems it is even common to use the NAT instance as … Read moreSSH key pair for access between instances in CloudFormation

Coordination between resources in AWS CloudFormation

One of the reasons I prefer CloudFormation over Terraform is access to Helper scripts. Many legacy applications are not built with statelessness and the installation depends on host information of other layers in the stack. This requires communication among instances during stack creation. The cloudformation Helper script (cfn-init, cfn-signal, cfn-hup and cfn-getmetadata) plays a key … Read moreCoordination between resources in AWS CloudFormation