4 Systems & infrastructure
Every entry filed under Systems & infrastructure and its subtopics.
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208 entries match these filters
- 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
- 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
- 0426 Sigma: the open detection-rule format for log data The SigmaHQ repository holds the vendor-neutral Sigma rule specification and a community library of thousands of detection rules that converters translate into… Any system Repo Detection & threat hunting · 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
- 0427 awesome-security: a curated map of security tools and learning resources A long-running awesome list that groups security software, reading material, courses, conferences and communities by area, from network and endpoint defence to… Any system Repo Security resources & detection 15 Oct 2026
- 0428 SecLists: wordlists for authorised security testing A large, maintained collection of wordlists (usernames, passwords, URLs, fuzzing strings, patterns) used in penetration tests with permission and in defensive checks… Linux, macOS Repo Security resources & detection · Security testing & CTF 15 Oct 2026
- 0429 PayloadsAllTheThings: a knowledge base organised by web vulnerability class A community-maintained reference that gives each class of web and application weakness its own section with background, detection notes and remediation references,… Any system Repo Security resources & detection · Security testing & CTF 15 Oct 2026
- 0430 HackTricks: a community wiki of security notes A large, continuously updated wiki of security study notes, organised like a textbook and published in GitBook style, used for learning, CTF… Any system Repo Security resources & detection · Security testing & CTF 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
- 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
- 0406 PowerShell: the cross-platform shell and scripting language The open-source PowerShell 7 project from Microsoft: an object-based shell and automation language that runs on Windows, Linux and macOS and is… Linux, macOS, Windows Repo PowerShell 15 Oct 2026
- 0417 Traefik: a reverse proxy that configures itself from Docker and Kubernetes Traefik is an open-source edge router that discovers services from Docker labels, Kubernetes resources and other providers and routes traffic to them,… Linux, macOS, Windows Repo Docker Compose · Web servers & reverse proxies 15 Oct 2026
- 0374 Alert rules that do not wake you for nothing How to design alerts people trust: alert on symptoms not causes, use for durations, separate page from ticket severities, group and inhibit… Intermediate · Explains an idea · Any system Article Alerting & dashboards 15 Oct 2026
- 0375 Fix: disk full, find what is eating the space A Linux filesystem reports 100 percent used or No space left on device. Find the culprit with df and du, check journals,… Intermediate · Fixes an error · Linux Article Alerting & dashboards · Disks, LVM & filesystems 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
- 0376 Loki: horizontally scalable log aggregation inspired by Prometheus The Grafana Loki repository: a log store that indexes labels instead of full text, queried with LogQL from Grafana or logcli, with… Linux, macOS Repo Logs 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
- 0377 Netdata: real-time, per-second monitoring with zero configuration The Netdata repository: an agent that auto-discovers hundreds of metrics on Linux hosts, containers and common services, shows them per second in… Linux, macOS Repo Alerting & dashboards · Prometheus & Grafana 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
- 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
- 0361 dev-sec ansible-collection-hardening: tested hardening roles for Linux, SSH and nginx An Ansible collection that applies a well-documented hardening baseline to Linux hosts, the SSH server and client, nginx and MySQL, with every… Linux Repo Ansible · Server hardening 15 Oct 2026
- 0367 verify-latest-backup: alert when the newest dump is too old or too small A read-only bash check that finds the newest file in a backup directory, compares its age and size against limits, optionally tests… Beginner · Step by step · Linux Script Backups & syncing · Strategy & restore drills 15 Oct 2026
- 0346 The SSH config file: aliases, jump hosts and keys per server Reference for ~/.ssh/config: short names for servers, the right user, port and key per host, ProxyJump through a bastion, connection reuse and… Intermediate · Cheat sheet · Linux, macOS, Windows Article Keys & config · SSH 15 Oct 2026
- 0368 restic: fast, encrypted, deduplicated backups to local disk, SFTP or cloud storage The restic repository: a single Go binary that backs up to local disks, SFTP, S3, Backblaze B2, Azure, Google Cloud and anything… Linux, macOS, Windows Repo Backup tools 15 Oct 2026
- 0349 Set up a WireGuard VPN with wg-easy in Docker Run a WireGuard server with a web admin page on one Linux host, open the UDP port, add a client from the… Intermediate · Guided project · Linux Article Networking & firewalls · VPN & tunnels 15 Oct 2026
- 0369 BorgBackup: deduplicating archiver with compression and authenticated encryption The BorgBackup repository: a Python and C backup tool that stores deduplicated, compressed, encrypted archives on local disks or over SSH, with… Linux, macOS Repo Backup tools 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
- 0370 rclone: rsync for cloud storage, with 70+ providers The rclone repository: a Go command-line tool that copies, syncs, mounts and checks files across local disks and more than 70 cloud… Linux, macOS, Windows Repo Backup tools 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
- 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
- 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
- 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
- 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
- 0350 wg-easy: WireGuard VPN with a web admin interface A Docker image that runs a WireGuard server and a web page to create clients, show QR codes and watch traffic. The… Linux Repo VPN & tunnels 15 Oct 2026