I frequently want to demonstrate the working of Apache Kafka and/or provide colleagues and other audiences with an environment for a workshop that involves Apache Kafka. I have been struggling to find a good way to get Kafka to function properly on Minikube – the standalone, single node Kubernetes cluster […]
Platform Technology
Exposing Kubernetes Services to the internet using Traefik Ingress Controller
Three services have been deployed to my Kubernetes cluster running on a public cloud environment. These services expose port for three underlying Pods and six or so containers. The service make the Pods accessible within the cluster – but not to the outside world, the public internet. For a […]
Minikube on KVM on Linux Mint 19.1
In a previous blog post I wrote about running Minikube on Windows. I ended with the suggestion that getting Minikube working might be much easier on Linux. Thus I installed Linux Mint (as dual-boot) on my laptop and gave it a shot. The steps I took to get it working […]
Enterprise Manager DataGuard Add Standby Database fails without showing errors at Destination Preparation phase
Oracle Enterprise Manager Cloud Control 13c provides the Add Standby Database wizard to create a broker configuration that includes a primary database and one or more standby database. This requires the Oracle Database Lifecycle Management Pack for Enterprise Manager Cloud Control. When adding a Standby Database, after proving all the […]
Weblogic 12c – Monitoring JVM Performance Metrics Using OEM and Java Mission Control
For Weblogic administrators and application devolopers, it may be desirable to view the JVM metrics from a managed server in OEM (CloudControl) and Java Mission Control. It is also possible to use the flight recorder with stored measurement data so that it can be analyzed at a later time. Issue: […]
First steps with Oracle Self Service Integration Cloud
An important part of enabling optimal use of SaaS applications is integrating various functions in said applications. Events in one application need to have an effect in others. From simple practical matters such as “send an email when a specific type of file was uploaded into a certain Dropbox or […]
Monitoring Spring Boot applications with Prometheus and Grafana
In order to compare the performance of different JDKs for reactive Spring Boot services, I made a setup in which a Spring Boot application is wrapped in a Docker container. This makes it easy to create different containers for different JDKs with the same Spring Boot application running in it. […]
Securing Oracle Service Bus REST services with OAuth2 client credentials flow (without using additional products)
OAuth2 is a popular authentication framework. As a service provider it is thus common to provide support for OAuth2. How can you do this on a plain WebLogic Server / Service Bus without having to install additional products (and possibly have to pay for licenses)? If you just want to […]
How to deploy InfluxDB in Azure using a VM service with dedicated storage
InfluxDB isn’t natively supported on Azure. This blog post will teach you how to deploy InfluxDB (or any other database) in a VM with a managed disk on the Azure platform. This will enable you to use this fast time-series database for your project. If the standard range of […]
From docker run to kubectl apply – quick Kubernetes cheat sheet for Docker users
Primarily for my personal reference: this article provides instructions on running a Docker container image as a Kubernetes Deployment plus Service. It compares the Docker run command with the approach for running on Kubernetes using a Yaml file and introduces some additional kubectl commands in the process. To work with […]
Java programs as native executables: GraalVM is the answer!
TL;DR: • Using GraalVM Java applications can be compiled into native standalone executables (will be demonstrated). • Native executables of small Java programs startup blazingly fast, use considerably less resources compared to running on JVM and do not even require the JRE or any other kind of runtime apart from […]
Docker host and bridged networking. Running library/httpd on different ports
Docker provides different networking options. When using the Docker host networking, you don’t have the option to create port mappings. When using images like library/httpd:2.4, you don’t have the option to update the port on which it runs; it runs by default on port 80. Suppose you want to use […]
Running Kubernetes 1.10 using MiniKube on Windows 10 (adding kubectl and helm/tiller)
Some quick steps to get Minikube for K8S 1.10 up and running on Windows 10 (presuming VirtualBox has already been installed) Download kubectl binary from: https://storage.googleapis.com/kubernetes-release/release/v1.11.0/bin/windows/amd64/kubectl.exe Copy kubectl.exe to any directory of your liking; add that directory to the PATH environment variable. Download minikube from https://github.com/kubernetes/minikube/releases Download the minikube-windows-amd64.exe file, […]
Running Spring Tool Suite and other GUI applications from a Docker container
Running an application within a Docker container helps in isolating the application from the host OS. Running GUI applications like for example an IDE from a Docker container, can be challenging. I’ll explain several of the issues you might encounter and how to solve them. For this I will use […]
VirtualBox networking explained
VirtualBox networking is extremely flexible. With this flexibility comes the challenge of making the correct choices. In this blog, the different options are explained and some example use cases are elaborated. Access between guests, host and other members of the network is explained and the required configuration is shown. This […]
My “Sinatra-Solution” for Error Code 235 of OMSPatcher 13.8.0.2
and How I resolved it …. My Way 235 … 235 … isn’t it an Interstate in Oklahoma? Is Oracle telling me that I’m now working with only 0.72% of all naturally occurring uranium? Was I testing the maximum speed of a BMW 3series? Or did somehow an Un-locked Control File […]
Running Istio on Oracle Kubernetes Engine–the managed Kubernetes Cloud Service
In a recent post, I introduced the managed Oracle Cloud Service for Kubernetes, the Oracle Kubernetes Engine (OKE): https://technology.amis.nl/2018/05/25/first-steps-with-oracle-kubernetes-engine-the-managed-kubernetes-cloud-service/. A logical next step when working with Kubernetes in somewhat challenging situations, for example with microservice style architectures and deployments, is the use of Istio – to configure, monitor and manage […]
First steps with Oracle Kubernetes Engine–the managed Kubernetes Cloud Service
Oracle recently (May 2018) launched its Managed Kubernetes Cloud Service (OKE – Oracle Kubernetes Engine) – see for example this announcement: https://blogs.oracle.com/developers/kubecon-europe-2018-oracle-open-serverless-standards-fn-project-and-kubernetes. Yesterday I got my self a new free cloud trial on the Oracle Public Cloud (https://cloud.oracle.com/tryit). Subsequently, I created a Kubernetes cluster and deployed my first pod on […]
Rapidly spinning up a VM with Ubuntu and Docker–on my Windows machine using Vagrant and VirtualBox
I have a Windows laptop. And of course I want to work with Docker containers. Using the Docker Quickstart Terminal is one way of doing so, and to some extent that works fine. But whenever I want to have more control over the Linux environment that runs the Docker host, […]
SOA Suite 12c in Docker containers. Only a couple of commands, no installers, no third party scripts
For developers, installing a full blown local SOA Suite environment has never been a favorite (except for a select few). It is time consuming and requires you to download and run various installers after each other. If you want to start clean (and you haven’t taken precautions), it could be […]