Interpreting fsck_hfs result

Question

While trying to understand why my Mac stopped performing so well on Spotlight.. I tried a suggestion that had me check my HD's status on Disk Utility. I can't press the Unmount button even after using First-Aid, weird. So this led me to searching this link - an old one but informative - and tried the commands there.

For the two other commands I got the expected result. Using sudo fsck_hfs -f /dev/disk0s2 or -fy, however.. (-y for Always attempt to repair any damage that is found ) while this is expected:

I got the following result. Same when typed -f in place of -fy.

This seemed troublesome. But shame I don't have a clue what is the issue nor how to deal with it. Could anyone share some insight please?

Answer 1

You are trying to check the file system on disk0s2 with the wrong tool. fsck_hfs targets HFS file systems. Your main drive is formatted to APFS though.

The output of sudo fsck_hfs -fy /dev/disk0s2 in your screenshot shows the first block of the/an APFS container. This is indicated by the NXSB magic string in the third line.

The proper tool to check APFS containers or volumes is fsck_apfs!

Check man fsck_apfs for further details.

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Since diskutil verifyDisk|verifyVolume|repairDisk|repairVolume [device] also calls fsck_apfs or another appropriate fsck_* tool with the proper flags I'd prefer this command instead:

diskutil list # to get the device identifiers
diskutil verifyDisk disk0
diskutil verifyVolume disk0s2
diskutil verifyVolume disk1s1

If required, repair the container/volume with:

diskutil repairDisk disk0s
diskutil repairVolume disk0s2
diskutil repairVolume disk1s1