Build a three-node Kubernetes v1.37 cluster on Proxmox VE 9.2: a cloud-init Ubuntu 24.04 template, three cloned VMs, containerd, kubeadm, kubelet, Flannel, then deploy nginx, expose it with a NodePort, scale it and drain a node, with every command run for real in a lab.

Read the guide · Watch on YouTube

nmtui on Ubuntu Server 24.04: turn on NetworkManager, then set a static IPv4 address, a bridge, a VLAN and the hostname from the text menu, with the keys, the netplan files it writes and the nmcli equivalents, every step run for real.

Read the guide · Watch on YouTube

A tour of the Proxmox VE 9.2 web interface on a real install: sign in, the 401 repository fix, storage, bridges and VLANs, a VM, a container, snapshots, backups, users and API tokens.

Read the guide · Watch on YouTube

The VMware-to-Proxmox word map, importing OVF files and VMDK disks (tested), what the import does not bring over (the NIC), UEFI, VirtIO…

Read the guide · Watch on YouTube

Tested on a real install of Proxmox VE 9.2: the installer screen by screen, the 401 repository fix, storage, bridges and VLANs, VMs, containers…

Read the guide · Watch on YouTube

Receive-only mail in Docker: Postfix, Roundcube and a contact form, with no way to send

Read the guide · Watch on YouTube

Writing, calling, pinning, refactoring and testing modules, with the errors and traps found by running every case, no cloud account needed

Read the guide · Watch on YouTube

Contexts, reading and shaping output, the failure gallery, rollouts, RBAC and admission errors, safe habits

Read the guide · Watch on YouTube

Popeye is a read-only scanner for Kubernetes clusters. It looks at what is actually deployed and reports misconfigurations…

Read the guide · Watch on YouTube

Kustomize cheat sheet: bases and overlays that change Kubernetes YAML without copying it.

Read the guide · Watch on YouTube

git cheat sheet: everyday commands for commits, branches, merging, stashing, history and undoing mistakes.

Read the guide · Watch on YouTube

k9s is a terminal dashboard for Kubernetes. It shows your cluster live (pods, deployments, nodes, logs) and lets you describe, edit, shell into…

Read the guide · Watch on YouTube

What reset --hard really destroys, deleted branches, dropped stashes, undoing rebase, amend and merge, force-push recovery on a server…

Read the guide · Watch on YouTube

Git for Beginners: Git is a tool that remembers every version of your files.

Read the guide · Watch on YouTube

A read-only evidence script and eleven runbooks reproduced on a real engine: restart back-off, the 10-second docker stop, OOM kills, UID mismatches…

Read the guide · Watch on YouTube

Docker Compose runs a whole application made of several containers (a web app, a database, a cache) from one YAML file.

Read the guide · Watch on YouTube

Exit codes, crash loops, Compose file checks, networking, disk, memory and daemon problems, in the order to investigate

Read the guide · Watch on YouTube

Create a virtual machine with nothing but the base system: a ZFS volume for a disk, a private network, a serial console…

Read the guide · Watch on YouTube

Gloves made once, in a clean workshop, and worn on every machine you own.

Read the guide · Watch on YouTube

The manager that turns the long bhyve command line into vm create, vm install and vm start, with a tested walkthrough: install, boot, network…

Read the guide · Watch on YouTube

A real backup routine between two FreeBSD machines: full and incremental sends, a restore test checked with checksums…

Read the guide · Watch on YouTube

Share a ZFS dataset from one FreeBSD machine and mount it on another, with the user-ID surprise, the access-list trap that let the wrong network…

Read the guide · Watch on YouTube

A working encrypted tunnel from nothing but the base system, with the keys, the config file, the proof that the traffic is encrypted, the AllowedIPs trap…

Read the guide · Watch on YouTube

How a cloud image configures itself with nobody at the keyboard: a config disk, a first-boot flag, a new user, an SSH key, a package, a bigger disk.

Read the guide · Watch on YouTube

Numbered rules where the first match wins, tables, logging and built-in traffic shaping, tested with real traffic, and the way not to lock yourself out

Read the guide · Watch on YouTube

Follow a FreeBSD boot from the disk to the login prompt, learn which settings belong in loader.conf and which in sysctl.conf…

Read the guide · Watch on YouTube

Run standard OCI container images on FreeBSD with Podman. See that a container is a jail, build an image…

Read the guide · Watch on YouTube

FreeBSD can run Linux programs directly, with no virtual machine. Switch it on, install a Rocky Linux userland, run real Linux software…

Read the guide · Watch on YouTube

Four layers of monitoring, each tested: the live tools, the nightly report, your own checks run by cron, and metrics with alerts.

Read the guide · Watch on YouTube

Patch what is vulnerable, shut the SSH door properly, hide your processes from other users, cut the listening ports…

Read the guide · Watch on YouTube

A tested walkthrough of a patch update and a full release upgrade (15.0 to 15.1) on a real FreeBSD system, with an undo button you actually tried

Read the guide · Watch on YouTube

Mittens or gloves? Pre-built packages fit most hands. The ports tree lets you cut software to fit yours: your options, your modules, your CPU

Read the guide · Watch on YouTube

Write a pf ruleset, block and allow real traffic from outside, redirect a port into a jail, ban an address without a reload, and read the log.

Read the guide · Watch on YouTube

You already know Linux. Here is the short, tested tour of what changes when the machine in front of you runs FreeBSD

Read the guide · Watch on YouTube

Create a pool, set quotas, take snapshots, roll back, clone, copy with send/receive, and watch ZFS repair a damaged disk, all tested on a throwaway pool

Read the guide · Watch on YouTube

Build a jail from scratch, start it, install a web server inside it, clone it with ZFS and see exactly what a jailed root cannot do

Read the guide · Watch on YouTube

entr on Ubuntu 24.04: run tests, restart a server or rebuild automatically whenever a file changes, with a file list from a pipe; the -c, -r, -s, -p, -d, -z and -n options and the /_ placeholder, every one run for real.

Read the guide · Watch on YouTube

zoxide on Ubuntu 24.04: a smarter cd that remembers the folders you visit and jumps to them from a few letters; z, zi, zoxide query, add and remove, ranking by use, and shell setup, with every command run for real.

Read the guide · Watch on YouTube

tldr (tealdeer) on Ubuntu 24.04: short, community-written examples for a command instead of the full manual, for subcommands, other platforms, with your own pages and patches, offline cache and settings, with every command run for real.

Read the guide · Watch on YouTube

ncdu on Ubuntu 24.04: scan a folder, see the biggest items first, go into folders, sort, delete from inside, save a scan to a file and open it later, and leave things out, with every key run for real.

Read the guide · Watch on YouTube

fzf on Ubuntu 24.04: filter files, command history, folders and any list by typing a few letters, with preview, multi-select, Ctrl-R, Ctrl-T and Alt-C key bindings, and filter mode for scripts, with every command run for real.

Read the guide · Watch on YouTube

worktrunk (wt) on Ubuntu 24.04: create, switch, list, merge and remove Git worktrees by branch name, with the shell moving you into each folder, with every command run for real on a sample repository.

Read the guide · Watch on YouTube

kondo on Ubuntu 24.04: find old projects and delete their node_modules, target, build and other rebuildable folders; dry run, age filter, ignore a folder, answer per project or clean all, with every command run for real on sample projects.

Read the guide · Watch on YouTube

grex on Ubuntu 24.04: give it example strings and it prints a regular expression that matches them; digits, repeats, spaces, case, anchors, files and standard input, tested with grep and Python, with every command run for real.

Read the guide · Watch on YouTube

llmfit on Ubuntu 24.04: read your CPU, RAM and GPU, rank thousands of language models by how well they fit, search, compare, plan hardware and simulate a bigger GPU, in the terminal and in scripts, with every command run for real.

Read the guide · Watch on YouTube

croc on Ubuntu 24.04: send a file, a folder or a line of text to another computer with a short code phrase, with no account and no open ports; zip, exclude, choose your own phrase, refuse a transfer, with every command run for real.

Read the guide · Watch on YouTube

oxker on Ubuntu 24.04: a terminal screen for Docker containers with live state, CPU, memory, logs and graphs; sort, filter, inspect, stop and start, open a shell and save logs, with every key run for real.

Read the guide · Watch on YouTube

gitlogue on Ubuntu 24.04: replay a Git commit, a range of commits, one author's work or your own staged changes in the terminal, typed out by a ghost developer with syntax highlighting, with every option run for real.

Read the guide · Watch on YouTube

VisiData on Ubuntu 24.04: open CSV and JSON files in the terminal, sort, count values with a frequency table, drill down, select rows, build a pivot table, save and convert, with every key run for real.

Read the guide · Watch on YouTube

Helm 4 guide for Ubuntu 24.04: repositories and charts, releases and values, writing your own chart, templates, schemas, upgrades and rollbacks, waiting and rollback on failure, hooks, CRDs, subcharts, publishing to a repository and an OCI registry, release storage, and troubleshooting, all run on a k3s lab.

Read the guide · Watch on YouTube

Kubernetes guide for Ubuntu 24.04 with k3s: how a cluster works, deployments and rolling updates, services and ingress, ConfigMaps and Secrets, volumes and StatefulSets, jobs, requests and limits, probes, scheduling and drain, autoscaling, NetworkPolicy, RBAC and quotas, etcd backup and restore, upgrades, Helm and Kustomize, all run on a two-node lab.

Read the guide · Watch on YouTube

Terraform guide for Ubuntu 24.04: reading plans and spotting forces replacement, state, drift and refresh-only plans, variables and precedence, for_each against count, import blocks, moved and removed blocks, lifecycle settings, workspaces, remote state with locking, secrets in the state, CI guards, OpenTofu and a cheat sheet, all run on a lab.

Read the guide · Watch on YouTube

Ubuntu authd with Microsoft Entra ID, tested on Ubuntu 24.04: register the app, install authd and the msentraid broker, tenant and client IDs, allowed users and the owner, device code and Entra sign-in flows, SSH login, groups and sudo, authctl, logs, public-key SSH and offline login risks, cloud-init, and the real errors Microsoft returns.

Read the guide · Watch on YouTube

Docker guide for Ubuntu 24.04: install and the docker group, running and managing containers, why docker stop takes ten seconds, logs and inspect, images and tags, Dockerfiles and the build cache, multi-stage builds, volumes and bind mounts, networks and name resolution, Compose, memory and CPU limits, log rotation, security settings, cleanup, troubleshooting by exit code, all tested on a lab.

Read the guide · Watch on YouTube

Config repos, etckeeper, blame and bisect, deploying with hooks, rollbacks, secrets and server settings

Read the guide · Watch on YouTube

yq guide for Ubuntu 24.04: which yq to install (the Go program, not the apt package), reading and editing YAML in place without losing comments, many documents and files, merging, anchors, converting between YAML, JSON, XML, TOML and properties, Docker Compose and Kubernetes examples, safe use in shell scripts, errors, speed, and how it differs from jq, all tested on a lab.

Read the guide · Watch on YouTube

jq guide for Ubuntu 24.04: the filter language, options, select and map, building and updating JSON, grouping and sorting, strings, regular expressions and dates, real data from ip, lsblk and a web API, safe use in shell scripts, error messages, big files, and what changed in jq 1.8, all tested on a lab.

Read the guide · Watch on YouTube

Semaphore UI guide for Ubuntu 24.04: install the package and Ansible, SQLite or PostgreSQL, keys, repositories, inventories and templates, running tasks from the API, dry runs and limits, email alerts on failure, schedules, git webhooks, collections, roles and users, remote runners, nginx, backup and restore, all tested on a lab.

Read the guide · Watch on YouTube

Grafana Loki guide for Ubuntu 24.04: install Loki, Alloy and logcli from the apt repository, a real configuration, shipping nginx logs with Alloy, labels and cardinality, LogQL queries and metrics, alert rules to Alertmanager, Loki in Grafana, nginx basic auth, multi-tenancy, retention and deletion, all tested on a lab.

Read the guide · Watch on YouTube

Grafana guide for Ubuntu 24.04: install from the apt repository, first login, grafana.ini and environment settings, provisioned data sources and dashboards, the HTTP API, users, teams and service accounts, alert rules, webhook and email notifications, nginx on a sub-path, plugins, backup and restore, all tested on a lab.

Read the guide · Watch on YouTube

Zabbix 7.0 LTS guide for Ubuntu 24.04: install the server, PostgreSQL and web frontend, the agent, hosts and templates, items and triggers, email alerts, acknowledge, maintenance, zabbix_sender, macros, PSK encryption and the API, all tested on a lab.

Read the guide · Watch on YouTube

Prometheus guide for Ubuntu 24.04: install Prometheus, node_exporter, Alertmanager and the blackbox exporter, scrape configs, PromQL, recording and alerting rules, silences, email and webhook alerts, basic auth and storage, all tested on a lab.

Read the guide · Watch on YouTube

superfile (spf) guide: install the terminal file manager, move around, search, copy, move, delete to trash, select many files, compress, extract, configure, cd on quit and script it, all tested on Ubuntu 24.04.

Read the guide · Watch on YouTube

Nagios Core guide for Ubuntu 24.04: install, config layout, hosts and services, plugins and exit codes, soft and hard states, NRPE remote checks, email alerts, acknowledgements, downtime, passive checks and securing the web interface, all tested on a lab.

Read the guide · Watch on YouTube

Checkmk Raw Edition guide: run a site in Docker, add hosts, install and register the agent, service discovery, rules and thresholds, local checks, email notifications, acknowledge and downtime, Livestatus queries, REST API and backup, all tested on a lab.

Read the guide · Watch on YouTube

Active Directory Login with SSSD: By the end of this tutorial a Linux server will be a member of your Windows Active Directory (AD) domain.

Read the guide · Watch on YouTube

Samba cheat sheet: share folders with Windows and Linux clients, users and permissions, the recycle bin and troubleshooting.

Read the guide · Watch on YouTube

Install and configure Postfix as a send-only, relay or full mail server, with SPF, DKIM, DMARC, queue management and troubleshooting.

Read the guide · Watch on YouTube

Creating SSH Keys: An SSH key is a pair of files that replaces typing a password: a PRIVATE key that stays on your computer…

Read the guide · Watch on YouTube

Copy your key to servers, log in without a password, and lock down SSH

Read the guide · Watch on YouTube

Keys, CSRs, self-signed certs, your own CA and Let's Encrypt

Read the guide · Watch on YouTube

OpenSSL cheat sheet: keys, certificates, CSRs, checking TLS connections, hashing and encryption from the command line.

Read the guide · Watch on YouTube

A how-to manual: modes, labels, reading denials, semanage and restorecon, ports, booleans, custom modules, confined users and relabeling…

Read the guide · Watch on YouTube

MySQL cheat sheet: connect, create databases and users, run queries, back up and restore, and common admin tasks.

Read the guide · Watch on YouTube

MySQL replication setup: configure a source and a replica, take a consistent snapshot, start replication and check that it works.

Read the guide · Watch on YouTube

PostgreSQL cheat sheet: psql, roles and databases, queries, backups and restores, and safe handling of passwords.

Read the guide · Watch on YouTube

Install, use and lock down SSHFS, with a restricted read-only account

Read the guide · Watch on YouTube

Accounts, groups, shared folders, sudoers rules that are safe, audits and offboarding

Read the guide · Watch on YouTube

apt, dnf, zypper, pacman and apk side by side: repositories, trust, holds, patching and fixing broken packages

Read the guide · Watch on YouTube

Server and location matching, reverse proxy and load balancing, caching, HTTPS and security limits, with every behaviour and error reproduced on a lab

Read the guide · Watch on YouTube

Fast, safe copying and mirroring over SSH: the trailing slash, --delete with a dry run, excludes, snapshot backups and exit codes

Read the guide · Watch on YouTube

Building, signing, carrying, serving and updating offline mirrors for apt and dnf, with the sizes you really need, the tamper tests…

Read the guide · Watch on YouTube

A tested checker run against real TLS servers in every bad state: expired, expiring, wrong name, self-signed, missing intermediate…

Read the guide · Watch on YouTube

systemctl controls systemd, the init system and service manager on most modern Linux distributions.

Read the guide · Watch on YouTube

Beyond the basics: writing and debugging services, dependencies, templates, timers, sockets, limits and sandboxing

Read the guide · Watch on YouTube

Partitions, filesystems, fstab, LVM, RAID, swap, imaging and finding out why the disk is full

Read the guide · Watch on YouTube

Find the log line that matters: filter by unit, time, priority and text, follow live, and keep the journal from eating the disk

Read the guide · Watch on YouTube

Schedule syntax, the minimal environment that breaks scripts, the percent-sign trap, overlapping runs, logging and when to use a systemd timer

Read the guide · Watch on YouTube

Troubleshooting Active Directory: This guide is a working method for finding out WHY Active Directory logins are slow or failing.

Read the guide · Watch on YouTube

htop cheat sheet: read the live process view, sort and filter it, and send signals to stop a process safely.

Read the guide · Watch on YouTube

ps takes a SNAPSHOT of the processes running on the system: who started them, how much CPU and memory they use, how long they have been running…

Read the guide · Watch on YouTube

lsof means "list open files". On Linux, almost everything is a file: regular files, directories, devices, pipes and network sockets.

Read the guide · Watch on YouTube

Recover a Deleted File with /proc: You deleted a file you needed. If a running process still has that file open, Linux has NOT erased the data yet…

Read the guide · Watch on YouTube

strace cheat sheet: trace the system calls a process makes to find out why a program will not start, hangs or fails.

Read the guide · Watch on YouTube

ltrace cheat sheet: trace the library calls a program makes, with filters, timing and summaries for debugging.

Read the guide · Watch on YouTube

perf cheat sheet: profile CPU use and find hot spots on Linux with perf stat, record and report.

Read the guide · Watch on YouTube

Two minutes to a verdict: load average, CPU vs memory vs disk vs waiting, who is doing it, and what to do about it, safest actions first

Read the guide · Watch on YouTube

Which filesystem, data or inodes, what is big, why df and du disagree, and how to free space without making things worse

Read the guide · Watch on YouTube

Find the stage that failed (firmware, GRUB, kernel, initramfs, systemd) and the fix for each, with fstab checks you can run before the reboot

Read the guide · Watch on YouTube

An amd64 server asks for i386 files, why a missing [arch=amd64] breaks the update, the real error messages, and every way to fix it

Read the guide · Watch on YouTube

A how-to manual: zones, services, runtime vs permanent, rich rules, ipsets, port forwarding and policies, logging…

Read the guide · Watch on YouTube

A how-to manual: families and tables, handles, atomic rulesets, sets and maps, dynamic meters, chain priorities, NAT, tracing and safe changes…

Read the guide · Watch on YouTube

A how-to manual: enabling safely, defaults, allow/deny/limit, rule order, app profiles, outgoing control, NAT in before.rules…

Read the guide · Watch on YouTube

A how-to manual: tables and chains, rule order, stateful baselines, matches, NAT, ip6tables, saving…

Read the guide · Watch on YouTube

A deep dive into BPF filters: precedence, byte offsets, flags, payloads, IPv6, VLANs and fragments, and the cases where a filter silently matches nothing…

Read the guide · Watch on YouTube

Wireshark is the most widely used network protocol analyzer. It captures packets from a network interface (or opens a saved capture) and shows them…

Read the guide · Watch on YouTube

iftop cheat sheet: see which hosts are using your network bandwidth right now, with filters and display options.

Read the guide · Watch on YouTube

A how-to manual: bonding modes, active-backup and LACP, link monitoring, hashing, failover tests, netplan and NetworkManager, VLANs and bridges…

Read the guide · Watch on YouTube

dig cheat sheet: query DNS records, trace delegation, check resolvers and do reverse lookups from the command line.

Read the guide · Watch on YouTube

A how-to manual: authoritative and recursive servers, zone files, the serial number, a secondary server, TSIG, dynamic updates, split DNS…

Read the guide · Watch on YouTube

nmap ("Network Mapper") discovers hosts on a network, finds their open ports, and identifies the services and operating systems behind them.

Read the guide · Watch on YouTube

tcpdump captures and prints network packets as they cross an interface. It is the fastest way to answer "is the traffic actually arriving?" on a server…

Read the guide · Watch on YouTube

A layer-by-layer method: link, routes, DNS, ports, TLS and HTTP, with failures reproduced on a lab and playbooks for common symptoms

Read the guide · Watch on YouTube

Who is listening, who is connected and who owns the port: the modern replacement for netstat, with filters and what every column means

Read the guide · Watch on YouTube

ip Command: ip is the modern tool for viewing and changing network settings on Linux.

Read the guide · Watch on YouTube

Ansible configures servers over SSH. You list your machines in an inventory and describe the state you want in YAML playbooks.

Read the guide · Watch on YouTube

Ad-hoc commands, host patterns, modules, quick playbooks, previewing changes safely and debugging real errors

Read the guide · Watch on YouTube

From one playbook to a project you can maintain: roles, variable precedence, Jinja2 templates, handlers and their trap, rolling updates, vault and lint…

Read the guide · Watch on YouTube

Describe the machine, let Puppet make it so: resources, facts, dependencies, classes and modules, Hiera data, and a real server with agents…

Read the guide · Watch on YouTube

Recipes in Ruby, cookbooks, custom resources, attributes, roles, data bags, Policyfiles and a server with nodes, run for real with Cinc…

Read the guide · Watch on YouTube

A master and its minions, states in YAML with Jinja, grains and pillar, orchestration and schedules, plus masterless and agentless runs…

Read the guide · Watch on YouTube

tmux cheat sheet: sessions that survive disconnects, windows, panes, key bindings, copy mode and a starter config, with a video.

Read the guide · Watch on YouTube

The server is slow: a first-ten-minutes playbook for CPU, memory, disk and network

Read the guide · Watch on YouTube

Python is a readable, general-purpose language that is very popular for automation, scripting, web services, data work and tooling.

Read the guide · Watch on YouTube

A tested job runner with lock, timeout, logging, heartbeat pings and rate-limited alerts, failure vs silence, staleness checks…

Read the guide · Watch on YouTube

Filters, null handling and exit codes, building JSON without injection, CSV/TSV/sh output, reading JSON into bash, NDJSON logs and real JSON from ip…

Read the guide · Watch on YouTube

Recipes on a real log, mawk vs gawk (what breaks silently), CSV with quoted commas, awk and sed traps reproduced…

Read the guide · Watch on YouTube

What /bin/sh really is, the bashisms tested side by side on dash, bash and BusyBox, the silent failures, portable replacements and how to test for them

Read the guide · Watch on YouTube

A complete script with logging, dry-run, locking, traps and atomic output, its failure paths run on purpose…

Read the guide · Watch on YouTube

Spaces, globs and empty variables, the pipe that loses your counter, 10 less than 9, octal 08 and more: 22 classic traps with the real symptom and the fix

Read the guide · Watch on YouTube

Exactly when set -e fires and when it silently does not, pipefail and SIGPIPE, ERR and EXIT traps, exit codes, retries and background jobs…

Read the guide · Watch on YouTube

Dynamic scope, the four ways to return a result (and a 100x speed difference), the last-command status trap, call stacks, the nameref recursion bug…

Read the guide · Watch on YouTube

$@ vs $*, getopts and its surprises, long options with a loop or GNU getopt, subcommands, validation, defaults and precedence, all tested

Read the guide · Watch on YouTube

This tutorial teaches you to WRITE bash programs, step by step. Each lesson has a short explanation, code you can type in and run, what you should see…

Read the guide · Watch on YouTube

Install Oh My Posh, add it to bash, zsh or fish, pick a theme and customize your prompt, with a video.

Read the guide · Watch on YouTube

Practical recipes for engineers and sysadmins: heredocs, tee, dates, text tools, loops, scripts, logs, SSH and more

Read the guide · Watch on YouTube

curl cheat sheet: fetch URLs, send headers and data, follow redirects, check status codes and timing, and debug HTTPS from the command line.

Read the guide · Watch on YouTube

csh / tcsh: csh is the C shell, written by Bill Joy for BSD Unix. Its syntax looks like the C language (if (...) then, foreach, @ for math)…

Read the guide · Watch on YouTube

Fish Shell: fish is the "friendly interactive shell". Compared with bash it works better out of the box: suggestions as you type (from your history)…

Read the guide · Watch on YouTube

Zsh (the Z shell) is a powerful interactive shell that is very close to bash for everyday use, and adds a much stronger tab-completion system…

Read the guide · Watch on YouTube

Bash (the Bourne Again SHell) is the default shell on most Linux systems. It is both the command line you type into and a scripting language.

Read the guide · Watch on YouTube

grep, sed, awk, Python, bash and PCRE: dialects, patterns, traps and tested recipes

Read the guide · Watch on YouTube

Linux file permissions cheat sheet: owner, group and other, reading rwx, chmod, chown, umask, setuid and ACLs, with a video.

Read the guide · Watch on YouTube

find walks a directory tree and tests every file against your expression. With no starting point it uses the current directory (GNU find).

Read the guide · Watch on YouTube

tar bundles many files into one archive (a "tarball"). It only bundles; compression (gzip, bzip2, xz, zstd) is a flag on top.

Read the guide · Watch on YouTube

sed guide for Ubuntu 24.04: how the stream editor works, substitute, addresses and ranges, regular expressions, editing files in place (and what -i does to symlinks and hard links), multi-line work with N, D and the hold space, config file edits that can be repeated, shell scripts without injection, GNU and BusyBox differences, errors, speed, and a cheat sheet, all tested on a lab.

Read the guide · Watch on YouTube

awk guide for Ubuntu 24.04: fields and records, patterns, printf, variables, arrays, functions, regular expressions, reading several files, gawk and mawk differences, using awk safely in shell scripts, speed on big files, and a cheat sheet, all tested on a lab.

Read the guide · Watch on YouTube

grep guide for Ubuntu 24.04: patterns and regular expressions (basic, extended and Perl), context lines, recursive search and what it skips, binary and compressed files, locales and Unicode, using grep safely in shell scripts, grep against ripgrep and git grep, speed on big files, and a cheat sheet, all tested on a lab.

Read the guide · Watch on YouTube

Everything you learned on Ubuntu also works on Rocky Linux, a free rebuild of Red Hat Enterprise Linux.

Read the guide · Watch on YouTube

How the programs that run in the background are managed, and where to look when one of them misbehaves

Read the guide · Watch on YouTube

Edit files in the terminal with nano, and learn the four keystrokes that get you out of vi alive

Read the guide · Watch on YouTube

A five-minute health check you can run on any Linux machine: is there room, is there memory, and is the network alive?

Read the guide · Watch on YouTube

Connect small commands into powerful chains, send output into files, and turn what you typed into a script you can run again

Read the guide · Watch on YouTube

See what your computer is doing right now, run things in the background, and stop a program politely or firmly

Read the guide · Watch on YouTube

cat, head, tail, wc and grep: look inside files, and find the lines that matter

Read the guide · Watch on YouTube

Create, copy, rename and delete things, and the habits that keep you from deleting the wrong ones

Read the guide · Watch on YouTube

The prompt, pwd, ls and cd: how to find your way around without getting lost

Read the guide · Watch on YouTube

Somewhere you can break things for free: a disposable Ubuntu, so your own computer stays safe

Read the guide · Watch on YouTube

Who you are, what you are allowed to do, how to read those cryptic letters, and how to change them safely

Read the guide · Watch on YouTube

How Ubuntu installs, updates and removes software, why "apt update" comes first, and a first real use of sudo

Read the guide · Watch on YouTube