Articles

21 entries match these filters

0006 Testing with pytest: first tests, fixtures and parametrize pytest runs plain functions whose names start with test_ and reports every failing assert in detail. This guide covers setup, assertions, exceptions,… Intermediate · How-to · Any system Article Testing 15 Oct 2026
0036 Finding the commit that broke it: log, blame, and git bisect When something used to work and now does not, Git can point at the commit that changed it. Start with log and… Advanced · How-to · Any system Article Finding bugs · Reading history 15 Oct 2026
0038 The pull request workflow on GitHub A pull request asks to merge your branch into another one, with review and automated checks in between. This is the whole… Beginner · How-to · Any system Article Pull requests 15 Oct 2026
0039 A minimal GitHub Actions workflow that runs your tests Add one YAML file under .github/workflows and GitHub runs your tests on every push and pull request. Here is a small, explained… Intermediate · How-to · Any system Article GitHub Actions 15 Oct 2026
0052 Slice and summarize text with grep, sort, uniq, cut, awk and sed A handful of classic tools can filter, count, extract and rewrite text right in the terminal. This guide shows the patterns you… Intermediate · How-to · Linux, macOS Article Finding files & text · Text processing 15 Oct 2026
0053 Set up SSH keys: ssh-keygen, ssh-copy-id and ~/.ssh/config SSH keys let you log in to servers and push to Git hosts without typing a password. Create an ed25519 key, install… Beginner · How-to · Linux, macOS, Windows Article Keys & config 15 Oct 2026
0056 Docker Compose: run a small web app with a database Docker Compose describes several containers, their ports, volumes and environment in one compose.yaml file, then starts them all with docker compose up. Intermediate · How-to · Linux, macOS, Windows Article Docker basics · Docker Compose 15 Oct 2026
0067 Your first SQL queries: SELECT, WHERE, ORDER BY, LIMIT and GROUP BY Read data from a table, keep only the rows you want, sort them, take the first few, and summarize groups with COUNT,… Beginner · How-to · Any system Article Queries 15 Oct 2026
0074 pandas basics: read a CSV, filter rows and summarize with groupby Load a CSV into a pandas DataFrame, inspect it, filter rows with conditions, and compute totals per group, with the SQL equivalent… Intermediate · How-to · Any system Article Data analysis · Files & automation 15 Oct 2026
0117 Configure the OCI CLI for Oracle Private Cloud Appliance 3.x Point the standard OCI CLI at a PCA 3.x Compute Enclave: create an API key, write ~/.oci/config with the appliance as the… Intermediate · How-to · Any system Article Compute, networking & storage 15 Oct 2026
0118 Create a compute instance on PCA 3.x with the Compute Web UI or OCI CLI Launch a VM in the Private Cloud Appliance 3.x Compute Enclave: gather an image, shape, subnet and SSH key, then create the… Intermediate · How-to · Any system Article Compute, networking & storage 15 Oct 2026
0119 PCA 3.x networking basics: create a VCN, subnets and security lists On Private Cloud Appliance 3.x, instances need a VCN and a subnet. Create them in the Compute Web UI or OCI CLI… Intermediate · How-to · Any system Article Compute, networking & storage 15 Oct 2026
0120 Block volumes on PCA 3.x: create, attach and mount a data disk Add storage to a Private Cloud Appliance 3.x instance: create a block volume, attach it as paravirtualized, then format and mount it… Intermediate · How-to · Any system Article Compute, networking & storage 15 Oct 2026
0137 Helm basics: install a chart, override values, upgrade and roll back Helm installs packaged Kubernetes apps called charts. Learn to add a repository, install a release, customize it with values files, upgrade it… Intermediate · How-to · Any system Article Helm 15 Oct 2026
0150 Logging in with oc and working with OpenShift projects Install the oc client, log in with a password, browser or token, then create, switch and inspect projects. Covers where oc stores… Beginner · How-to · Any system Article Concepts · Deploying applications 15 Oct 2026
0151 Tutorial: deploy a small web app on OpenShift and expose it with a Route A step-by-step first deployment: create a project, build a static website from Git with Source-to-Image, publish it on an HTTPS Route, then… Beginner · How-to · Any system Article Deploying applications 15 Oct 2026
0152 Build and deploy from source with oc new-app and Source-to-Image How oc new-app turns a Git repository or an image into a running app, how Source-to-Image and Docker builds are chosen, and… Intermediate · How-to · Any system Article Deploying applications 15 Oct 2026
0153 Expose apps with OpenShift Routes: edge, passthrough and re-encrypt TLS A Route publishes a service on a host name through the OpenShift router. Learn when to use plain HTTP, edge, passthrough or… Intermediate · How-to · Any system Article Deploying applications · Ingress & networking 15 Oct 2026
0154 OpenShift app configuration: environment, ConfigMaps, Secrets and persistent storage Set environment variables, load ConfigMaps and Secrets into a Deployment as variables or files, and give it persistent storage with a PersistentVolumeClaim,… Intermediate · How-to · Any system Article Config, secrets & storage · Deploying applications 15 Oct 2026
0184 Ansible Vault: keep passwords and keys encrypted in your repo Ansible Vault encrypts variable files or single values so secrets can live in Git next to your playbooks. Create, edit and rekey… Advanced · How-to · Linux, macOS Article Ansible 15 Oct 2026
0189 Terraform remote state: backends, locking and migrating local state Move Terraform state from a local file into a shared backend such as S3 with locking, so a team can work safely.… Advanced · How-to · Any system Article Terraform 15 Oct 2026