Have you ever tried to find out the open ports in a Linux box without using the common tools like netstat, nmap, lsof, ss ... ? In some cases, the tools are just not available. e.g In a cutdown version Linux server or container, and you don't have the permission to install any software. I … Continue reading Find open ports from Linux kernel
Author: Jackie Chen
Run Hubot on OpenShift
In this article, I will demonstrate how to build a Hubot bot on OpenShift. Four key take-away points. Create secret for git clone Use docker strategy to build if you prefer Dockerfile over S2I Inject environment variables from ConfigMap If needed, you can replace the FROM or CMD that defined in Dockerfile during deployment. In … Continue reading Run Hubot on OpenShift
Autoscaler on OpenShift Dedicated
At the time of writing, OpenShift dedicated (v3.5.5.31) only supports autoscaling based on the CPU metrics. So the first step is to ensure the CPU request is in place. It can be setup in the section of container spec. e.g spec: containers: image: 'poc/web' name: my-web ports: - containerPort: 3000 resources: requests: cpu: 200m limits: … Continue reading Autoscaler on OpenShift Dedicated
Build smart into your docker images
We have been running mysql 5.7 on OpenShift with RedHat provisioned images. To make it work is easy, but to make it work correctly is a bit harder. One example is that how to setup the innodb_buffer_pool_size (one of the most important parameters of mysql)? When you build the image you don't know how much memory the … Continue reading Build smart into your docker images
Resources QoS in Kubernetes
I extracted a few points to grasp the rough idea of how Kubernetes manages resources QoS: Pods that need to stay up reliably can request guaranteed resources, while pods with less stringent requirements can use resources with weaker or no guarantee. If a pod is successfully scheduled, the container is guaranteed the amount of resources … Continue reading Resources QoS in Kubernetes
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