Cheat sheet
xargs cheat sheet
Turn lines of input into command arguments with xargs: safe handling of spaces, one command per item, placeholders, parallel jobs and dry runs.
linux
Cheat sheet
tmux cheat sheet
Keep SSH sessions alive and split your terminal with tmux: sessions, windows, panes, copy mode, the commands I use and a minimal config.
Cheat sheet
Text processing one-liners
Slice and reshape text on the command line with cut, tr, paste, column, comm, join, sort and awk: columns, CSV, joins and set operations.
Cheat sheet
tee cheat sheet
Save a command's output to a file while still passing it on: logging long jobs, writing root-owned files with sudo, and splitting a stream to several places.
Cheat sheet
systemctl cheat sheet
Manage systemd services with systemctl: status, restarts, enabling at boot, drop-in overrides, dependencies, timers and user services.
Cheat sheet
ssh cheat sheet
SSH keys, config, jump hosts, port forwarding, scp and sshd hardening: the commands and settings I use on every server.
Cheat sheet
sort and uniq cheat sheet
Sort lines by number, size, version or a single column, remove or count duplicates, and rank the most common values with sort and uniq.
Cheat sheet
Slow Linux server checklist
The first minutes on a slow Linux server: load, CPU, memory, disk I/O, network and the kernel log, with what each number means.
Cheat sheet
Shell shortcuts cheat sheet
Move faster in Bash: readline keys, history search and expansion, brace expansion, globbing and the small tricks that save typing.
Cheat sheet
sed cheat sheet
Find and replace, delete and print lines with sed, and edit config files in place safely, with the GNU and macOS differences.
Cheat sheet
Regex cheat sheet
Regular expressions for grep, sed and awk: the syntax, how basic, extended and Perl-style regex differ, and patterns for IPs, dates and log lines.
Cheat sheet
Network debugging cheat sheet
Find where a Linux network problem is: DNS, routing, ports, firewalls, TLS or packet loss, with dig, ip, ss, nc, mtr, curl and tcpdump.
