-
Use Python to Check Difference between Directories Recursively
I needed to track differences between software release packages, so that if anything changed dramatically, eg. some file missing or much smaller than expected, I can then get a notification to review the new potentially flawed package. I found that filecmp.dircmp class in Python is spot on for this job. Here’s my snippet to compare…
-
Upload Limit in Kubernetes Nginx Ingress Controller
According to https://github.com/nginxinc/kubernetes-ingress/issues/21#issuecomment-408618569, this is how to lift the upload limit in Nginx Ingress Controller for Kubernetes after recent update to the project: apiVersion: extensions/v1beta1 kind: Ingress metadata: name: test-project-ingress namespace: test-project-dev annotations: kubernetes.io/ingress.class: dev nginx.ingress.kubernetes.io/proxy-body-size: 200m spec: rules: – host: test-project.dev.com http: paths: – path: / backend: serviceName: test-project servicePort: 80 And for now…
-
Auto Scaling in Kubernetes 1.9
I updated my Kubernetes cluster from 1.8 to 1.9 recently, the upgrade process is very smooth, however the auto-scaling part seemed to be failing. Below are some notes on how I troubleshoot this issue. First to ensure I have both kops and kubectl upgraded to 1.9 on my laptop: Install kubectl 1.9: curl -LO https://storage.googleapis.com/kubernetes-release/release/v1.9.10/bin/linux/amd64/kubect…
-
Command Line Recording Goes SVG
Term To SVG is lovely little utility to record a terminal session into a .svg animation. And below is a recording of how I installed termtosvg myself on Arch Linux.
-
Manage AWS EBS Snapshot Life Cycle with Lambda
The timing is not so great. The AWS Data Lifecycle Manager has been announced but I can’t wait for its release. So I decided to use AWS Lambda to do some snapshot lifecycle management. First a role for Lambda having full access to snapshots can be created via the console. To create snapshot with Python…
-
Building Dynamic CI Pipeline with BuildKite
I was inspired by this BuildKite pipeline sample given by the support team: So in the above case, if the first 2 commands succeed, pipeline.deploy.yml will be loaded into the main CI pipeline. This implementation is just brilliant. I’m not sure if jenkinsfile can do dynamic pipeline like this, but at least jenkinsfile won’t look…
-
Playing with Kubernetes Ingress Controller
It’s very very easy to use Kubernetes(K8s) to provision an external service with AWS ELB, there’s one catch though(at least for now in 2018). AWS ELB is usually used with an auto scaling group and a launch configuration. However with K8s, EC2 instances won’t get spun directly, only pods will, which is call Horizontal Scaling.…
-
Profiling Tomcat Remotely with Java Mission Control
I was interested to see why a tomcat app runs very slow. In the tooling stage, I picked Java Mission Control(jmc) because it’s a built-in of Oracle Java 8. To enable jmc and its flight recorder, I added the following Java switches to tomcat’s setenv.h file: Having restarted tomcat, double check if the port is…