4 Systems & infrastructure
Every entry filed under Systems & infrastructure and its subtopics.
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57 entries match these filters
- 0454 Scan your own code and containers in CI: Gitleaks, Semgrep and Trivy Set up a GitHub Actions workflow that runs Gitleaks, Semgrep and Trivy on every push of your own project, learn what each… Intermediate · Step by step · Any system Article Pipelines, runners & hooks · Security testing & CTF 15 Oct 2026
- 0432 Try Sigma rules against your own logs Install the sigma-cli converter, take a rule from the public SigmaHQ library, convert it into a query for a log tool you… Intermediate · Step by step · Linux, macOS Article Logs · Security resources & detection 15 Oct 2026
- 0403 Work across Windows and WSL: files, paths and running tools from both sides WSL is most useful when Windows and Linux cooperate: open Linux folders in Explorer, run Windows programs from bash, convert paths with… Beginner · Step by step · Windows Article Basics · WSL 15 Oct 2026
- 0420 cron and systemd timers: run something every night Schedule a script with crontab or a systemd timer: the five cron fields, environment and PATH pitfalls, logging, catching up missed runs… Beginner · Step by step · Linux Article cron & timers · Services & systemd 15 Oct 2026
- 0400 winget: install and update software from the command line winget is the package manager built into Windows. Search for a program, install it by id, update everything with one command and… Beginner · Step by step · Windows Article Installing languages & tools · Windows administration 15 Oct 2026
- 0401 Windows services, Task Scheduler and event logs from PowerShell Manage the three things Windows administrators touch most: query and restart services, create and inspect scheduled tasks, and search the event logs… Intermediate · Step by step · Windows Article PowerShell · Windows administration 15 Oct 2026
- 0373 Loki: ship and search logs Run Loki, Grafana Alloy and Grafana with Docker Compose, collect the systemd journal and /var/log files with a short Alloy configuration, and… Intermediate · Step by step · Linux Article Logs 15 Oct 2026
- 0391 Install Docker on Linux, macOS and Windows Docker Desktop or Docker Engine? Pick the right one for your OS, install it, and confirm with docker run hello-world. Covers the… Beginner · Step by step · Linux, macOS, Windows Article Docker basics · Installing languages & tools 15 Oct 2026
- 0394 Install kubectl on Linux, macOS and Windows Install the Kubernetes command-line client with curl, a package manager or winget, verify it, and point it at a cluster with a… Beginner · Step by step · Linux, macOS, Windows Article Concepts · Installing languages & tools 15 Oct 2026
- 0398 Install WSL2 and Ubuntu on Windows One command installs the Windows Subsystem for Linux and Ubuntu. Then learn how to pick a distribution, check which WSL version you… Beginner · Step by step · Windows Article Windows administration · WSL 15 Oct 2026
- 0352 Harden a fresh Linux server in 30 minutes The baseline for any new Debian, Ubuntu or RHEL-family server: updates on, a non-root user with sudo, SSH keys only, a firewall… Beginner · Step by step · Linux Article Server hardening · Users, sudo & hardening 15 Oct 2026
- 0353 fail2ban: block repeated failed logins Install fail2ban, enable the sshd jail with sane ban times, whitelist your own address, read the ban list, unban someone, and add… Intermediate · Step by step · Linux Article Server hardening · SSH 15 Oct 2026
- 0354 sudo rules: give a user exactly the rights they need Write sudoers rules with visudo: full admin for operators, a short list of commands for a deploy account, no-password rules for automation,… Intermediate · Step by step · Linux Article Secrets & access · Users, sudo & hardening 15 Oct 2026
- 0356 Free HTTPS with Let’s Encrypt and certbot Install certbot, get a trusted certificate for your domain and let it configure nginx or Apache, or just obtain the files for… Beginner · Step by step · Linux Article TLS & certificates 15 Oct 2026
- 0357 Keep secrets out of git: .env files, gitignore and what to do after a leak Load passwords and API keys from an untracked .env file, commit a safe .env.example instead, catch mistakes before they are pushed, and… Beginner · Step by step · Any system Article Housekeeping · Secrets & access 15 Oct 2026
- 0363 Restore drill: prove your backup works in 15 minutes A repeatable procedure to restore one file and one database from your newest backup into a scratch location, compare the result with… Intermediate · Step by step · Linux, macOS Article Backup tools · Strategy & restore drills 15 Oct 2026
- 0364 Schedule PostgreSQL and MySQL dumps with systemd timers Write one dump script for PostgreSQL and MySQL, run it from a systemd service and timer instead of cron, keep two weeks… Intermediate · Step by step · Linux Article Backup tools · PostgreSQL 15 Oct 2026
- 0365 Proxmox Backup Server: first setup and first restore Install Proxmox Backup Server, create a datastore and a backup user, connect it to Proxmox VE as storage, run the first VM… Intermediate · Step by step · Linux Article Backup & restore · Backup tools 15 Oct 2026
- 0371 Where are the logs? journalctl, /var/log and container logs A practical map of where Linux programs write their logs and the commands to read them: journalctl filters, the classic files under… Beginner · Step by step · Linux Article Logs 15 Oct 2026
- 0372 Grafana: your first dashboard from Prometheus data Connect Grafana to a Prometheus server, build a four-panel host dashboard with PromQL queries, set units and thresholds, add an instance variable,… Beginner · Step by step · Browser, Linux, macOS Article Prometheus & Grafana 15 Oct 2026
- 0344 ufw and firewalld: open and close ports Allow and remove ports and services on the two standard Linux host firewalls, restrict a port to one source network, and make… Beginner · Step by step · Linux Article Firewalls · Networking & firewalls 15 Oct 2026
- 0345 SSH keys: create, copy and use them Generate an ed25519 key pair, install the public key on a server with ssh-copy-id, keep the private key protected with a passphrase… Beginner · Step by step · Linux, macOS, Windows Article Keys & config · SSH 15 Oct 2026
- 0328 Install Docker Engine on Ubuntu and Debian Set up Docker's official apt repository, install Docker Engine with the Compose and Buildx plugins, run hello-world and let your user run… Beginner · Step by step · Linux Article Docker basics · Packages & updates 15 Oct 2026
- 0330 Write a Dockerfile: FROM, COPY, RUN, CMD and multi-stage builds How a Dockerfile turns into an image layer by layer, what the main instructions do, how to order them for fast rebuilds,… Intermediate · Step by step · Linux, macOS, Windows Article Docker basics · Images & registries 15 Oct 2026
- 0331 docker compose for an app with a PostgreSQL database A compose.yaml that runs your application next to a PostgreSQL container, with a named volume for the data, a health check so… Intermediate · Step by step · Linux, macOS, Windows Article Docker Compose · Install & connect 15 Oct 2026
- 0332 Tag, push and pull images with Docker Hub and other registries How image names map to registries, how to log in, tag and push an image to Docker Hub, GitHub Container Registry or… Intermediate · Step by step · Linux, macOS, Windows Article Images & registries 15 Oct 2026
- 0342 Which process is using a port, and how to free it Find the program behind a busy port with ss, lsof or fuser, decide whether to stop it properly or kill it, and… Beginner · Step by step · Linux, macOS Article DNS, IP addresses & ports · Networking & firewalls 15 Oct 2026
- 0169 Add a new disk: partition, format and mount it by UUID Find a new disk with lsblk, partition it with parted, create an ext4 or XFS filesystem and mount it permanently through /etc/fstab… Intermediate · Step by step · Linux Article Disks, LVM & filesystems 15 Oct 2026
- 0173 Set a static IP address: nmcli on RHEL vs netplan on Ubuntu RHEL, Rocky and AlmaLinux configure networking with NetworkManager (nmcli); Ubuntu Server uses netplan YAML. Here is the same static IP setup in… Intermediate · Step by step · Linux Article Networking & firewalls 15 Oct 2026
- 0175 Open ports with firewalld and ufw firewalld (RHEL, Rocky, AlmaLinux) and ufw (Ubuntu) are friendly front ends to the kernel firewall. Allow SSH first, then open only the… Intermediate · Step by step · Linux Article Networking & firewalls 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 · Step by step · 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 · Step by step · Any system Article Terraform 15 Oct 2026
- 0192 Grafana basics: connect Prometheus, build a dashboard and set up an alert Connect Grafana to Prometheus, build a dashboard for your servers with PromQL panels and a host selector, and create an alert rule… Intermediate · Step by step · Linux Article Prometheus & Grafana 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 · Step by step · Any system Article Config, secrets & storage · Deploying applications 15 Oct 2026
- 0165 Write a systemd service unit for your own app Turn any long-running program into a proper service: create a unit file, run it as an unprivileged user, restart it on failure… Intermediate · Step by step · Linux Article Services & systemd 15 Oct 2026
- 0166 Replace a cron job with a systemd timer A systemd timer runs a service on a schedule like cron, but logs every run to the journal, can catch up missed… Intermediate · Step by step · Linux Article Services & systemd 15 Oct 2026
- 0135 Deploy your first app on Kubernetes A step-by-step tutorial: write a Deployment and a Service in YAML, apply them, reach the app, add health probes, roll out a… Beginner · Step by step · Linux Article Ingress & networking · Workloads & services 15 Oct 2026
- 0136 Persistent storage in Kubernetes: PersistentVolumes, claims and StorageClasses How to give a Pod storage that survives restarts: request it with a PersistentVolumeClaim, let a StorageClass provision it, and mount it.… Intermediate · Step by step · Linux Article Config, secrets & storage · Workloads & services 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 · Step by step · Any system Article Helm 15 Oct 2026
- 0138 Kubernetes RBAC basics: least-privilege access for a service account RBAC controls who may do what in a cluster with Roles, ClusterRoles and bindings. This guide grants a CI service account deploy… Advanced · Step by step · Linux Article Concepts · Config, secrets & storage 15 Oct 2026