Before a maintenance window you want to know whether the unmounted XFS filesystem on /dev/sdb1 is damaged, without letting anything be modified. Type the complete command that checks it and reports what it would do, in no-modify mode.
LPIC-1 Exam 101-500, objective 104. Devices, Linux filesystems, filesystem hierarchy standard medium
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Answer
Type the answer.
Accepted answer
xfs_repair -n /dev/sdb1
Case sensitive — Linux is, and grading LS as ls would teach a falsehood.
Why
xfs_repair -n scans the filesystem and prints the repairs it would carry out, but opens the device read-only and changes nothing. It is the XFS counterpart of e2fsck -n (xfs_repair takes short options only, so there is no --no-modify spelling), and the safe first move whenever the extent of the damage is unknown. Note that plain fsck does almost nothing on XFS, and that xfs_repair still requires the filesystem to be unmounted even in no-modify mode.
Where this comes from
- Cited
- manual page xfs_repair(8)
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 104 and space the ones you get wrong.
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