Staying capable as systems change.
WHAT CHANGES
Init systems, network tooling and package managers have all been replaced within living memory.
WHAT THAT MEANS
Commands learned years ago may be deprecated or absent.
WHAT REPLACED WHAT RECENTLY
ip replaced ifconfig and route ss replaced netstat systemctl replaced service and chkconfig journalctl supplements text log files
WHY OLD COMMANDS STILL APPEAR IN GUIDES
The internet does not update, and old answers rank well.
WHAT TO DO
Check the manual on your own system before trusting an example.
WHAT TO FOLLOW
Release notes for the distributions you run Security announcements for what you operate
WHY SECURITY ANNOUNCEMENTS SPECIFICALLY
They are the difference between patching before and after an exploit.
WHAT TO PRACTISE
New tooling on a machine that does not matter.
WHAT NOT TO DO
Adopt something new on a production server to learn it.
WHAT TO REVISIT PERIODICALLY
Whether your habits still reflect the best available approach.
WHAT TO RESIST
Changing things that work, for novelty.
WHAT TO PRIORITISE LEARNING
Whatever you had to look up twice.
WHAT TO WRITE DOWN
The answer, the second time.
