Files and paths · Lesson 20 of 36 · 8 minutes

Filesystem checkpoint

Verify archive, checksum, and search habits.

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Your objectives

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1
Create checkpoint archive
Run tar -cf lab/fs-check.tar README.txt.
Hint & worked example
Practice archive inventory, creation, and extraction in a simulated archive format.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
tar -cf lab/fs-check.tar README.txt
```
Remember: These training archives are virtual data structures, not downloadable production tar files.
2
List checkpoint archive
Run tar -tf lab/fs-check.tar.
Hint & worked example
Practice archive inventory, creation, and extraction in a simulated archive format.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
tar -tf lab/fs-check.tar
```
Remember: These training archives are virtual data structures, not downloadable production tar files.
3
Hash README
Run sha256sum README.txt.
Hint & worked example
Compare content digests to detect byte changes, not to establish who authored the file.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
sha256sum README.txt
```
Remember: A checksum detects changes only relative to a trusted expected digest.
4
Find README paths
Run find /home/learner -name README.
Hint & worked example
Search directory trees by criteria rather than relying on one shallow listing.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
find /home/learner -name README
```
Remember: Quote wildcard patterns so find receives them instead of the shell expanding them first.

Understand the pattern

Junior operators build confidence by gathering evidence before changing systems.

tar: Practice archive inventory, creation, and extraction in a simulated archive format.
These training archives are virtual data structures, not downloadable production tar files.
sha256sum: Compare content digests to detect byte changes, not to establish who authored the file.
A checksum detects changes only relative to a trusted expected digest.
find: Search directory trees by criteria rather than relying on one shallow listing.
Quote wildcard patterns so find receives them instead of the shell expanding them first.

Worked example and expected result

$ tar -cf lab/fs-check.tar README.txt

created archive /home/learner/lab/fs-check.tar

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

$ tar -tf lab/fs-check.tar

README.txt

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

$ sha256sum README.txt

a76968d5df26cfd59ecd7d080f8283d65e91ec7366d233b4b98233877aa154c6  /home/learner/README.txt

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

$ find /home/learner -name README

/home/learner/README.txt

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 “Filesystem checkpoint”, which interpretation is safe?These training archives are virtual data structures, not downloadable production tar files.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 tar workflow from “Filesystem checkpoint” 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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