Package/process ops · Lesson 14 of 20 · 8 minutes

Process lookup drill

Find process IDs and compare snapshots.

Open the lab Course map

Mastery 0/3Run itExplain itApply it

learner@clairos:~ $

↑ history · Tab complete · Ctrl+C cancel · Esc, Tab to leaveExit 0

Your objectives

Hints are always available. Wrong turns never cost XP.

1
Find nginx
Run pgrep nginx.
Hint & worked example
Find simulated process IDs by a name pattern.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
pgrep nginx
```
Remember: Verify a process identity before sending a signal.
2
Show processes
Run ps.
Hint & worked example
Inspect a bounded snapshot of simulated processes.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
ps
```
Remember: A process being present does not prove that its service can handle requests.
3
Show top
Run top.
Hint & worked example
Inspect a single training snapshot of process and resource activity.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
top
```
Remember: This lab does not run a continuously refreshing process monitor.

Understand the pattern

Junior operators build confidence by gathering evidence before changing systems.

pgrep: Find simulated process IDs by a name pattern.
Verify a process identity before sending a signal.
ps: Inspect a bounded snapshot of simulated processes.
A process being present does not prove that its service can handle requests.
top: Inspect a single training snapshot of process and resource activity.
This lab does not run a continuously refreshing process monitor.

Worked example and expected result

$ pgrep nginx

Exit status: 0. The command completed successfully in the training fixture.

$ ps

PID  USER      COMMAND
1    root      systemd --simulated
42   www-data  nginx: static process
77   root      sshd: listener
108  learner   clairos-learn-terminal
126  root      cron

Exit status: 0. The command completed successfully in the training fixture.

$ top

top - 10:26:04 up 12 days, 1 learner, load average: 0.04, 0.03, 0.01
PID USER      %CPU %MEM COMMAND
42  www-data   0.2  1.1 nginx
77  root       0.1  0.8 sshd
126 root       0.0  0.3 cron

Exit status: 0. The command completed successfully in the training fixture.

Try a variation

Repeat this workflow in the sandbox with a different scratch filename. Keep the system fixtures unchanged and compare the observed output with your expectation before moving on.

Explain it

In “Process lookup drill”, which interpretation is safe?A process being present does not prove that its service can handle requests.A command appearing in history proves it completed successfully.A successful first check guarantees that every dependent service is healthy.

Apply it elsewhere

Before adapting the ps workflow from “Process lookup drill” to another server, what should you do?Paste the training paths unchanged into production.Skip output inspection whenever the command is familiar.Confirm the current directory, target identity, permissions, and the installed command behavior first.

Keep the momentum.

Complete the lab, then explain and apply the pattern.

Next: Signal choice review Try an incident drill

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