The kernel primitives, init systems, and tooling behind the world's most-deployed OS.
A complete walkthrough reading, changing, and persisting kernel runtime parameters — with a few of the most commonly tuned examples explained, not just listed.
A complete walkthrough encrypting a disk or partition with LUKS, from initial setup through mounting it automatically (with a key file) at boot.
A complete walkthrough using strace to see exactly which system calls a misbehaving program is making — often the fastest way to diagnose a problem with no useful log output at all.
A complete walkthrough from raw disks to a mounted, resizable logical volume — physical volumes, volume groups, and logical volumes explained as you build them.
Ping by IP works but hostnames don't resolve. Here's a systematic path through resolv.conf, systemd-resolved, and nsswitch.conf to find where resolution is actually breaking.
An application errors out with EMFILE or ENFILE, even though the system clearly isn't out of resources in any obvious sense. Here's how to find and raise the actual limit involved.
Load average is climbing but top shows plenty of idle CPU. This almost always means processes stuck waiting on I/O, not a CPU problem — here's how to actually find which one.
On January 22, 2007, the Open Source Development Labs and the Free Standards Group combined into the Linux Foundation, consolidating Linux's economic and standards-setting efforts under one organization.
When kernel developers lost free access to the proprietary BitKeeper in April 2005, Torvalds responded by writing an entirely new version control system himself — Git's first commit landed within days.
Released March 14, 1994 at 176,250 lines of code, version 1.0 was the point Linus Torvalds and the community considered the kernel stable enough for production use.