4 Systems & infrastructure
Every entry filed under Systems & infrastructure and its subtopics.
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230 entries match these filters
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 0360 certbot: the Let’s Encrypt client The EFF's ACME client that obtains free TLS certificates from Let's Encrypt, can configure nginx and Apache for HTTPS automatically and renews… Linux Repo TLS & certificates 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
- 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
- 0347 Port check script: test a list of host:port pairs with timeouts A bash script that tries a TCP connection to each host:port you give it, waits a few seconds at most, and reports… Beginner · Cheat sheet · Linux, macOS Script DNS, IP addresses & ports · Firewalls 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
- 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
- 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
- 0348 DNS check script: compare answers from several resolvers A bash script that looks up one or more names against your system resolver and three public resolvers, shows each answer with… Beginner · Cheat sheet · Linux, macOS Script DNS, IP addresses & ports 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
- 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
- 0358 SSH server audit script: print risky sshd settings A read-only bash script that asks sshd for its effective configuration, compares the important settings with safe values, flags config.d files that… Intermediate · Cheat sheet · Linux Script Server hardening · SSH 15 Oct 2026
- 0351 Pi-hole: network-wide ad blocking with your own DNS server A DNS server for your home or office network that answers queries for known advertising and tracking domains with nothing, so every… Linux Repo DNS, IP addresses & ports · VPN & tunnels 15 Oct 2026
- 0359 fail2ban: ban hosts that fail to log in too often The standard intrusion-prevention daemon on Linux servers: it watches logs or the journal for repeated failures and adds temporary firewall rules against… Linux Repo Server hardening · SSH 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
- 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
- 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
- 0366 restic backup wrapper with tagging, retention and a weekly check A bash wrapper that runs restic backup on a fixed list of paths, applies a keep-daily/weekly/monthly policy with forget and prune, runs… Intermediate · Step by step · Linux, macOS Script Backup tools · Backups & syncing 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
- 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
- 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
- 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
- 0335 Docker cleanup script with dry run and confirmation A bash wrapper around docker system prune that shows disk usage and lists what would be removed, supports a dry-run flag, and… Beginner · Step by step · Linux, macOS Script Docker basics · Shell scripting 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
- 0325 Fix: SSL certificate problem: unable to get local issuer certificate curl, git, pip or npm cannot chain the server's certificate to a root they trust. Usual causes: a corporate proxy that re-signs… Intermediate · Fixes an error · Linux, macOS, Windows Article Common errors · Making requests · TLS & certificates 15 Oct 2026
- 0336 Back up and restore a Docker named volume to a tar archive A bash script that copies the contents of a named Docker volume into a .tar.gz on the host, and restores an archive… Intermediate · Step by step · Linux, macOS Script Backup tools · Docker basics 15 Oct 2026
- 0322 Fix: user is not in the sudoers file sudo refuses because your account is not allowed to use it. Add the user to the sudo group (Debian, Ubuntu) or wheel… Beginner · Fixes an error · Linux, macOS Article Server hardening · Users, sudo & hardening 15 Oct 2026
- 0338 Watchtower (maintained fork): automatic container image updates Watchtower watches your running containers, pulls newer versions of their images and restarts them with the same settings. This fork continues the… Linux Repo Docker basics · Images & registries 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
- 0339 Uptime Kuma: self-hosted uptime monitoring Uptime Kuma is a self-hosted monitoring tool with a web UI that checks websites, TCP ports, DNS, Docker containers and more, draws… Linux, macOS, Windows Repo Alerting & dashboards · Docker basics 15 Oct 2026