Permissions and users · Lesson 32 of 33 · 8 minutes

Service account ownership

Relate a web file owner to the identity used by its service.

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Your objectives

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1
Inspect the web file owner
Run stat /srv/www/index.html.
Hint & worked example
Inspect a file or directory metadata record, including ownership, permissions, and size.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
stat /srv/www/index.html
```
Remember: Metadata and file contents answer different questions.
2
Inspect the service account
Run id www-data.
Hint & worked example
Inspect user identity and group membership.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
id www-data
```
Remember: A file group is useful only when the acting user belongs to it or has an applicable override.
3
Relate ownership to the service
Run systemctl status nginx.
Hint & worked example
Inspect or change a simulated systemd service. Status, active state, and unit configuration reveal different evidence.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
systemctl status nginx
```
Remember: A service can be active while an application endpoint is unhealthy; verify both layers.

Understand the pattern

Matching service identities with file ownership helps operators explain what they know before they change anything.

stat: Inspect a file or directory metadata record, including ownership, permissions, and size.
Metadata and file contents answer different questions.
id: Inspect user identity and group membership.
A file group is useful only when the acting user belongs to it or has an applicable override.
systemctl: Inspect or change a simulated systemd service. Status, active state, and unit configuration reveal different evidence.
A service can be active while an application endpoint is unhealthy; verify both layers.

Worked example and expected result

$ stat /srv/www/index.html

Path: /srv/www/index.html
Type: file
Mode: -rw-r--r--
Owner: www-data
Group: www-data
Size: 72 bytes

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

$ id www-data

uid=33(www-data) gid=33(www-data) groups=33(www-data)

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

$ systemctl status nginx

nginx.service - simulated nginx
   Loaded: loaded
   Active: active
   Notes: serving the simulated static learn site

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 “Service account ownership”, which interpretation is safe?A file group is useful only when the acting user belongs to it or has an applicable override.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 id workflow from “Service account ownership” 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.

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