Tukuk-OSAfter years of using the terminal I noticed that90 percent of my work uses only about ten commands. The rest I look up again when needed. This is the list I rewrote on my first day of learning Linux, and the same list I still use every day to maintain Tukuk-OS.
1. ls -la — See Everything
The first command I memorised. ls lists the contents of a folder, -a shows hidden files (those starting with a dot, like .env), and -l gives full details: owner, permissions, size, and date. When I am confused about "where is this file?", this is the answer.
2. cd — Change Place
cd changes the current directory. I use cd .. to go up one level, cd - to return to the previous directory, and cd ~ to go home. These three variants alone save me from typing full paths over and over.
3. pwd — Where Am I?
When I dive too deep into a project folder and lose my bearings, pwd (print working directory) prints the full path. Tiny, but it saves me from creating files in the wrong place.
4. grep — Find Text Inside Files
grep -r "error" logs/ searches for the word "error" in every file under the logs directory. I use this whenever something goes wrong. The grep -i version ignores case, and grep -n adds line numbers so I can jump straight to the location.
5. cat and less — Read Files
cat prints an entire file to the screen. For long files I use less because it lets me scroll. tail -f shows the contents of a file live — very useful for watching server logs while I test a change.
6. systemctl — Control Services
On modern Ubuntu, systemctl status tukuk-os tells me whether my server is alive, systemctl restart tukuk-os restarts it, and journalctl -u tukuk-os shows the logs. These three commands are the heartbeat of Tukuk-OS daily operations.
7. ps and top — Who Is Eating Resources?
ps aux lists all processes, while top (or htop) shows live CPU and memory usage. When the server is slow these are the first two commands I run to find the culprit.
8. chmod and chown — File Permissions
Hidden files like .env contain secret keys. chmod 600 .env ensures only the owner can read it. chown changes the owner. Permission mistakes are the most common reason a server fails to start, and both commands solve it in five seconds.
9. df -h and du -sh — Disk Almost Full?
df -h shows overall disk space remaining, while du -sh folder shows the size of each folder. Whenever storage runs low I hunt the largest folders with du -sh * | sort -h.
10. curl — Test From Outside
curl -I https://tukuk.org sends a HEAD request and shows the response code. curl localhost:8000/health tests the server directly before I open a browser. To me, curl is the stethoscope of a server administrator.
A Real Session Using the Whole List
To show how these ten work together, here is a real session fixing a problem on the Tukuk-OS server one evening. The server had slowed down, so I started with top and saw one process consuming an abnormal amount of memory. I used ps aux to identify the process precisely, then systemctl status to see whether it was a service I recognised.
Next I needed to know whether the problem was new or old. pwd confirmed my current directory, ls -la showed log files with their dates, and tail -f opened the log live so I could watch what happened as I restarted the service. Inside the log I searched for the word "timeout" with grep -r, which led me to a particular configuration file.
Before touching that file I read it with less, then checked its permissions with ls -la to make sure the owner was correct. After making the change I restarted the service with systemctl restart, verified the response with curl localhost:8000/health, and finally checked disk space with df -h to make sure logs were not filling the storage.
The whole session took about ten minutes and used almost the entire list. None of the commands are special — the value is in how they are arranged into one smooth problem-solving process.
Why Memorise a Little, Search a Lot
I do not memorise a hundred commands. I memorise ten that unlock everything, and I know where to find the rest. That is real terminal skill: not memory, but the ability to investigate. With just these ten commands you can already maintain a production web server completely — even one like Tukuk-OS.