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Clairos Learn

33 lessons · UNIX / Linux

Permissions and users

Modes, owners, groups, and sensitive file review.

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What you will practice

Permissions; Owners and groups; Permission review; Numeric modes.

Use the worked examples when needed, then test your understanding without them.

  1. 01PermissionsRead and change simulated modes and ownership without risking real files.Practice
  2. 02Owners and groupsPractice simulated chown and chgrp changes while checking account context.Practice
  3. 03Permission reviewReview sensitive training SSH and web files with long listings and metadata.Practice
  4. 04Numeric modesSet and inspect numeric file modes.Practice
  5. 05Directory modesReview why private directories use tighter modes.Practice
  6. 06Owner reviewChange simulated owner and group labels on a web file.Practice
  7. 07Passwd and group filesRead training account and group records.Practice
  8. 08Sudoers reviewRead a simulated sudoers drop-in without granting power.Practice
  9. 09Public and private filesCompare web-readable and private-note permissions.Practice
  10. 10Protected pathsTry a blocked system delete and inspect the protected file.Practice
  11. 11Group collaborationCreate a shared lab note and set group-oriented metadata.Practice
  12. 12Temporary directory conceptInspect simulated /tmp and keep scratch work inside home.Practice
  13. 13Executable scriptsRead and mark a training deploy script executable.Practice
  14. 14Sensitive path auditFind and inspect sensitive configuration paths.Practice
  15. 15Test file typesCheck file and directory types before changing modes.Practice
  16. 16Sticky bit reviewInspect shared temporary directory metadata.Practice
  17. 17Script private modeSet strict metadata on a script draft.Practice
  18. 18Ownership auditCompare service account ownership across web files.Practice
  19. 19Link permission reviewReview link metadata and target permissions together.Practice
  20. 20Permissions checkpointReview modes, groups, ownership, and sensitive paths.Practice
  21. 21SSH directory auditReview SSH directory and file modes together.Practice
  22. 22Known hosts reviewInspect known_hosts as sensitive SSH context.Practice
  23. 23Service user ownershipCompare service users with files they serve.Practice
  24. 24Shared directory riskInspect shared directories before trusting their contents.Practice
  25. 25Sudoers readonly reviewRead a limited sudo rule without changing privileges.Practice
  26. 26Web root mode reviewSet and verify public web file permissions.Practice
  27. 27Group write riskSpot group ownership before changing modes.Practice
  28. 28Least privilege auditReview identity, service ownership, and sensitive modes.Practice
  29. 29Directory traversal modesSet and inspect a directory mode that supports controlled traversal.Practice
  30. 30Shared group directoryPrepare a group-owned workspace and inspect its collaboration mode.Practice
  31. 31SSH mode matrixCompare directory and key-file modes used by an SSH account.Practice
  32. 32Service account ownershipRelate a web file owner to the identity used by its service.Practice
  33. 33Least privilege bridgeCheckpoint ownership, group assignment, and minimum useful modes.Practice