4 Systems & infrastructure
Every entry filed under Systems & infrastructure and its subtopics.
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49 entries match these filters
- 0455 Which security tool does what? A map for beginners A beginner's map of open source security tool families: vulnerability scanners, secret detection, static analysis, host audits, web application testing, network inventory… Beginner · Explains an idea · Any system Article Security resources & detection · Server hardening 15 Oct 2026
- 0443 Security monitoring explained: IDS, SIEM, EDR and where the logs go A plain language map of the security monitoring tool families, what each one watches, how they feed one another, and where the… Beginner · Explains an idea · Any system Article Detection & threat hunting · Logs 15 Oct 2026
- 0431 What is a detection rule? Sigma explained for beginners A detection rule describes one kind of suspicious activity in logs. Sigma is the shared, tool-independent way to write such rules, so… Beginner · Explains an idea · Any system Article Alerting & dashboards · Security resources & detection 15 Oct 2026
- 0433 What is an awesome list? Awesome lists are hand-curated link collections on GitHub, one per subject, that follow a shared convention. How they work, how to tell… Beginner · Explains an idea · Any system Article Security resources & detection 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
- 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
- 0404 Find the largest folders on a drive with PowerShell Lists the biggest top-level folders under a path, with file counts and sizes in GB, so you can see where the disk… Beginner · Step by step · Linux, macOS, Windows Script PowerShell · Windows administration 15 Oct 2026
- 0405 Export the list of installed programs to CSV with PowerShell Reads the Windows uninstall registry keys and writes name, version, publisher and install date of every installed program to a CSV file.… Beginner · Step by step · Windows Script PowerShell · Windows administration 15 Oct 2026
- 0399 Fix: running scripts is disabled on this system (execution policy) PowerShell refuses to run .ps1 files until the execution policy allows it. The usual fix is RemoteSigned for your own user; here… Beginner · Fixes an error · Windows Article PowerShell · Windows administration 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
- 0396 PowerShell basics: cmdlets, objects and the pipeline PowerShell commands are called cmdlets, they return objects instead of text, and the pipeline passes those objects between them. Once that clicks,… Beginner · Explains an idea · Linux, macOS, Windows Article PowerShell 15 Oct 2026
- 0397 PowerShell cheat sheet The PowerShell cmdlets and patterns you use every day: files, text, processes, services, filtering, exporting, remoting and the operators that trip up… Beginner · Cheat sheet · Linux, macOS, Windows Article PowerShell 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
- 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
- 0355 TLS certificates explained What a certificate proves, who signs it, what the chain and expiry mean, and how to read any site's certificate from the… Beginner · Explains an idea · Any system 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
- 0362 The 3-2-1 backup rule, and why a backup you never restored is not a backup Three copies, two kinds of media, one off-site: what the rule really protects against, how it maps to real tools, and why… Beginner · Explains an idea · Any system Article Strategy & restore drills 15 Oct 2026
- 0327 Docker images, containers and volumes explained An image is a read-only template, a container is a running copy of it with a thin writable layer, and a volume… Beginner · Explains an idea · Linux, macOS, Windows Article Docker basics 15 Oct 2026
- 0329 Docker CLI cheat sheet The Docker commands you reach for every day, grouped by what they act on: containers, images, volumes, networks, logs and cleanup, with… Beginner · Cheat sheet · Linux, macOS, Windows Article Docker basics 15 Oct 2026
- 0334 Fix: port is already allocated docker run or docker compose up fails with Bind for 0.0.0.0:8080 failed: port is already allocated. Find what holds the port, another… Beginner · Fixes an error · Linux, macOS, Windows Article Docker fixes · Processes & ports 15 Oct 2026
- 0340 Build and run a small Python web app in a container Write a tiny Flask app, give it a Dockerfile, build the image, run it with a published port, make a change and… Beginner · Guided project · Linux, macOS, Windows Article Basics · Docker basics · Images & registries 15 Oct 2026
- 0310 What is a cluster? A cluster is a group of computers working together as one system so that if one fails the others keep the service… Beginner · Explains an idea · Any system Article Clusters & high availability 15 Oct 2026
- 0311 What is Kubernetes? Kubernetes is a system that runs containers across many servers, restarting, scaling and connecting them automatically. Beginner · Explains an idea · Any system Article Concepts 15 Oct 2026
- 0312 What is a pod? A pod is the smallest unit Kubernetes runs: one or more containers that share a network address and storage. Beginner · Explains an idea · Any system Article Workloads & services 15 Oct 2026
- 0291 What is a log? A log is a running record of what a program did and when, written to a file so you can look back… Beginner · Explains an idea · Any system Article Logs 15 Oct 2026
- 0306 What is hashing? Hashing turns any data into a fixed length fingerprint that cannot be reversed, used to check files and store passwords. Beginner · Explains an idea · Any system Article Secrets & access 15 Oct 2026
- 0307 What is encryption? Encryption scrambles data with a key so only someone with the right key can read it again. Beginner · Explains an idea · Any system Article TLS & certificates 15 Oct 2026
- 0308 What is a backup snapshot? A snapshot is a frozen picture of a disk or system at one moment that you can roll back to if something… Beginner · Explains an idea · Any system Article Strategy & restore drills 15 Oct 2026
- 0309 What is RAID? RAID combines several disks into one so data survives a disk failure or is read and written faster. Beginner · Explains an idea · Any system Article Disks, LVM & filesystems 15 Oct 2026
- 0268 What is a container? A container is a lightweight box that packs a program with everything it needs so it runs the same on any computer. Beginner · Explains an idea · Any system Article Docker basics 15 Oct 2026
- 0272 What is a virtual machine? A virtual machine is a complete computer made of software, running inside another computer with its own operating system. Beginner · Explains an idea · Any system Article Basics 15 Oct 2026
- 0273 What is a hypervisor? A hypervisor is the software layer that creates and runs virtual machines and shares the real hardware between them. Beginner · Explains an idea · Any system Article Basics 15 Oct 2026
- 0274 What is DNS? DNS is the internet's phone book: it turns names like example.com into the IP addresses computers actually use. Beginner · Explains an idea · Any system Article DNS, IP addresses & ports 15 Oct 2026
- 0275 What is an IP address? An IP address is the unique number that identifies a device on a network so data knows where to go. Beginner · Explains an idea · Any system Article DNS, IP addresses & ports 15 Oct 2026
- 0276 What is SSH? SSH is a secure way to open a command line on another computer over the network, with everything encrypted. Beginner · Explains an idea · Any system Article SSH 15 Oct 2026
- 0277 What is TLS? TLS is the encryption layer that puts the S in HTTPS, protecting data between your browser and a server. Beginner · Explains an idea · Any system Article TLS & certificates 15 Oct 2026
- 0278 What is a certificate? A certificate is a digital ID card that proves a website or server is genuine, issued by a trusted authority. Beginner · Explains an idea · Any system Article TLS & certificates 15 Oct 2026
- 0280 What is a firewall? A firewall is a filter that decides which network connections are allowed in or out of a computer or network. Beginner · Explains an idea · Any system Article Firewalls 15 Oct 2026
- 0281 What is a package manager? A package manager is a tool that installs, updates and removes software for you and keeps track of what depends on what. Beginner · Explains an idea · Any system Article Packages & updates 15 Oct 2026