Resources in Oracle Cloud Infrastructure can be managed through the console – the browser based UI. That works great but requires manual steps – no automation – that take time and easily go wrong (and become extremely boring over time). Additionally, it is a rather individualistic way of working that […]
Writing a blog in Word, automating HTML formatting by using a .docx to HTML converter for Java and publishing the blog via WordPress (part 1)
At AMIS, gaining and sharing information and knowledge is part of our DNA, so that’s why the AMIS Technology Blog has been there for over 15 years now. Together with my colleagues on a regular basis, I write blog articles. From the beginning we used WordPress, but over the years […]
Setup and use of oVirt on CentOS7
Today, I’ll explain how to install and use oVirt: a nice virtualization tool for Linux, which is based on KVM. I installed the current production version 4.3.8 on a test machine, a Medion machine with an extra SSD drive. As usual, you’ll find the installation file for pxe that I […]
Set Terraform Resource properties from an element in a list retrieved by a Data Source – using a local value
Terraform is a platform for implementing Infrastructure as Code. Terraform defines a syntax for describing resources and provides an engine that interprets the resources definitions, compares this desired state with the existing state in the destination environment and subsequently attempts to bring the destination in line with the desired state. […]
Secure browsing using a local SOCKS proxy server (on desktop or mobile) and an always free OCI compute instance as SSH server
Oracle provides several services as ‘always free’. In contrast to Azure and Amazon, these include compute instances which remain ‘forever’ free to use. Although there are some limitations on CPU, disk, network resources, these instances are ideal to use as a remote SSH server and with a little effort a […]
Using PXE to deploy a DNS server
Last week, I published a blog about implementing a PXE server [1]. Today I’ll show how kickstart/anaconda files can be used to deploy a server. I will use the example of a DNS-server to explain what can be changed where in kickstart files and what you can do when the […]
Oracle Database – more value for money and more value for free
Oracle is not known for low prices or free products. However, when it comes to the Oracle Database there are some developments that might be of interest to you. Either when your organization has existing Oracle Database licenses – or when you do not. In short: three powerful and until […]
Use OCI Monitoring, Alarms and Notifications for Your Own Custom and Functional Metrics
In earlier articles, I have discussed features in Oracle Cloud Infrastructure for monitoring metrics published by virtually all OCI services. These metrics get published when functions are invoked, files are written, the API Gateway handles a request, events are published, a user is created and a network transfers a packet. […]
Welcoming the Data Catalog Service on Oracle Cloud Infrastructure
Data is really important to any organization. Data tells us what the organization is doing, and where it is going. And how it can improve quality and efficiency of processes. Achieve better results. Data can be one of the key products an organization delivers to its customers. I am sure […]
Deploying CentOS 8 using PXE
What is PXE? PXE (Preboot eXecution Environment) is a method of deploying an operating system to a computer over the network. I think it’s great: you don’t need to burn CD’s or DVD’s anymore. The only thing you have to do is changing the boot order in the BIOS, and […]
Run Always Free Docker Container on Oracle Cloud Infrastructure
In this article, I want to show how you can very quickly run a Docker container for free on Oracle Cloud Infrastructure – using a VM in the Always Free Tier of OCI. As an example, I will run an NGINX container image and access that from a client over […]
Oracle Cloud Infrastructure Resource Monitoring – Alarm triggers Notification when Metrics satisfy Condition
Oracle Cloud Infrastructure gathers metrics from all OCI resources. These metrics can be visualized and analyzed with the Metrics Explorer. And Alarms can be defined with rules evaluating the metrics that publish to a Notification Topic to signal a situation of interest. Subscriptions can be defined on these Notification Topics, […]
HTTP benchmarking using wrk. Parsing output to CSV or JSON using Python
wrk is a modern HTTP benchmarking tool. Using a simple CLI interface you can put simple load on HTTP services and determine latency, response times and the number of successfully processed requests. It has a LuaJIT scripting interface which provides extensibility. A distinguishing feature of wrk compared to for example ab […]
jq – Linux command line tool for interpreting and manipulating JSON documents
I am not the first to discover jq, or even to write about it. However, jq was such a valuable tool for me that I felt obliged to share it with you. And turn it into a Katacoda scenario (Katacoda is on of my other favorite finds). jq is a […]
Trying out Project Fn handson – using only your browser
Project Fn is an open source framework for creating and running serverless functions. Project Fn produces a Docker container image for each function. This container has a runtime (for example for Java, Go, Python, Node) and a minimal handler to handle an HTTP request and turn it into a call […]
Further customizing a Grafana Custom Plugin in React
In my previous blog I created a custom plugin for Grafana with React and more specifically the Material UI TreeView. It’s possible to customize the plugin even further, as I will show you in this post. CSS Styling can be added when needed. Keep in mind that Grafana uses a […]
Rapidly spinning up a VM with Ubuntu and k3s (with the Kubernetes Dashboard) on my Windows laptop using Vagrant and Oracle VirtualBox
In November of last year, my colleague Lucas Jellema, wrote an article with the title “Ultra fast, ultra small Kubernetes on Linux – K3S beating minikube”. [https://technology.amis.nl/2019/11/12/ultra-fast-ultra-small-kubernetes-on-linux-k3s-beating-minikube/] For training and demo purposes, on my Windows laptop, I already had an environment with a guest Operating System, Docker and Minikube available […]
Somewhat Stateful Serverless Functions on Oracle Cloud Infrastructure – Implementing a DIY Cache
We call them serverless and we consider them stateless. Functions on Oracle Cloud Infrastructure (and on other cloud platforms). Of course they are neither. They run on servers. And they can carry some state, though largely opportunistic and not reliably. Functions on OCI run inside a container. The container is […]
JavaScript: Mapping and Wrapping Classic Callback Functions to Promises and Async / Await
Callback functions used to be very common in JavaScript and Node applications. Out of necessity. And with Callback functions came unclear program flows, parallel realities, nested complexity and more. ECMAScript introduced Promises several years ago and followed that up with the neat await and async syntax. This allows us to […]
Asynchronous Function Calls through API Gateway on Oracle Cloud Infrastructure
In a recent article, I described how serverless Functions on Oracle Cloud Infrastructure can invoke each other: synchronously and asynchronously. Although asynchronous calls are the desired state, such calls currently are possible only with quite a bit of hassle – using a Stream for queuing asynchronous requests and a Listener […]
OCI Serverless Functions invoking other Functions – synchronous and asynchronously through API Gateway and Streaming
OCI allows for cloud native application development, using facilities such as serverless functions, a light weight API gateway, a streaming service for asynchronous communication based on event messaging and built-in monitoring. In previous articles, I have gone over several aspects of serverless functions and API Gateways to create and expose […]
Using OCI Monitoring Healthchecks to Schedule execution of Serverless Functions on Oracle Cloud Infrastructure
Execution of scheduled jobs based on a time schedule is a frequent requirement. Jobs on Oracle Cloud Infrastructure are often implemented using cloud native, serverless Functions – that can be exposed through (public) HTTP endpoints on an API Gateway. I recently published an article describing how execution of functions can […]
Oracle Cloud Streaming Service – Scalable, Reliable, Kafka-like Event service on OCI
Oracle Cloud Infrastructure offers the Streaming service. This service is easily described as a Kafka-like fully managed event platform for high volume streams of data that can be processed in real or delayed time in a durable, reliable way. And from the documentation: “Streaming can be used for messaging, ingesting […]
Deprecated: (!First Steps) with Oracle Cloud’s Pub/Sub Service: Oracle Messaging Cloud Service
Fire and forget messaging is a powerful concept. Asynchronous, decoupled communication is key to scalability and independence of services. Oracle Cloud provides a pub/sub solution called Oracle Messaging Cloud Service. This is an HTTP based publish and subscribe mechanism for asynchronous communication – based on persistent messages and durable subscriptions. […]
Publish Oracle Function for Reading and Writing Object Storage Files through OCI API Gateway
The objective for this article is to show you how to get to the point where two routes are available on an API Gateway on Oracle Cloud Infrastructure that allow easy writing to a file on Object Storage and easy retrieval of such as file. Writing files is obviously useful […]
Oracle Cloud Infrastructure – Leveraging API Gateway as Read Only Cache from serverless Function
This article demonstrates a set up that is probably mainly of theoretical interest or maybe useful in demonstrations. I describe how we can invoke an OCI serverless Function through the API Gateway and ask the serverless function for values that are read from a [read only] cache. This cache is […]
Oracle Cloud API Gateway – Using an Authorizer Function for Client Secret Authorization on API Access
The objective in this article: create a simple Authorizer Function that checks the Client Secret passed in API calls and allows and denies requests based on whether the correct Client Secret is included. The Authorizer Function does a little more than simply accept or deny: in case of accept it […]
pgAdmin in Docker: Provisioning connections and passwords
pgAdmin is a popular open source and feature rich administration and development platform for PostgreSQL. When provisioning Postgres database environments using containers, it is not unusual to also provision a pgAdmin container. The pgAdmin image provided on Docker Hub does not contain any server connection details. When your pgAdmin container […]
Oracle Cloud Infrastructure Functions and Project Fn – Retrieving Headers, Query Parameters and other HTTP Request elements
Functions on Oracle Cloud Infrastructure are implemented using Project Fn. A function runs in Docker container. This container has a runtime (for example for Java, Go, Python, Node) and a minimal handler to handle an HTTP request and turn it into a call to the function. When writing the code […]
Oracle Cloud Serverless Functions unleashed: exposing OCI Functions through API Gateway
Oracle Cloud Infrastructure API Gateway makes it possible to expose OCI Functions on public endpoints that do not require complex signed HTTP requests. Any function that should be easily publicly accessible can be given such easy access. By creating an API Deployment on an API Gateway and associating a route […]
Scheduling Oracle Cloud Function execution
Functions on Oracle Cloud are an important element in any cloud native application architectures. Functions are typically small, well contained and fairly independent pieces of logic to carry out specific tasks. These tasks can be executed upon reception and handling of HTTP requests – a very common use case – […]
Override Date.now() based on OS time when Node returns incorrect current date
I was facing a weird issue. In my Node application – version 10.6.3 – running on Ubuntu – 18.04 – I got the wrong value for the current date and time. A call to new Date() and to Date.now() resulted in a wrong value, off by over two months: The […]
Finally, sftp from an Oracle database using plain plsql
Just a quick blog to get me through the Christmas eve. More than 5 years ago I wrote a blog about FTPS from an Oracle databse. In that blog I already mentioned that SFTP using plsql is possible. Not loading some Java classes in the database and adding some plsql […]
My Quick Start with Oracle Functions in Fresh OCI Tenancy
This article is fairly rough log of the steps I went through to get going on Oracle Cloud Serverless Functions. It is mainly intended to provide a note to myself, for future reference. However, my description could prove useful to you – the reader. My steps to get going are […]
Using bindings to connect Azure Functions to Azure Queue Storage
Recently I started working in the Azure Cloud and I would like to share an example I worked on that helped me understand the possibilities of this cloud environment. The focus for this article is using Azure Functions and Input and Output bindings to the Azure Queue Storage. The business […]
Apache Camel + Spring Boot: Different components to expose HTTP endpoints
Apache Camel is an open source integration framework that allows you to integrate technologically diverse systems using a large library of components. A common use-case is to service HTTP based endpoints. Those of course come in several flavors and there is quite a choice in components to use. In this blog post […]
My first steps with Oracle Cloud API Gateway – the stock response
The API Gateway service on Oracle Cloud Infrastructure went live very recently – read my overview article of what API Gateway entails. In brief: API Gateway is a reverse proxy that exposes HTTP endpoints on which external (or internal) clients can make requests. API Gateway can handle these requests: authorize, […]
Introducing Oracle Cloud API Gateway – the light weight public or private router to public and private OCI endpoints
Two days ago, the API Gateway service on Oracle Cloud Infrastructure went live – read the announcement. This is a crucial component for many applications and in many solution designs. This new API Gateway is a prime candidate for example for inclusion in our reference architecture for OCI based solution […]
Linux Shell Script – passing arguments to functions and returning and capturing results
Developing Linux Shell Scripts is just not the same as programming in modern programming language. At least to me, it still feels novel and at times a bit weird. I am currently engaged in some scripting that requires the use of functions. That is all well, but I want to […]
ADF Performance Monitor – Major New Version 9.0 (Part 1)
I’m very excited to announce that we have a major new version of the ADF Performance Monitor – version 9.0 ! We have added many valuable new features; new metrics that can detect and help explain poor performance, disruptions, hiccups, and help troubleshooting ADF applications. Like operating system metrics: the […]