I am trying to check an entire USB external disk that is not erased. For that reason I have typed
fsck_hfs -fy -l -S -d /dev/disk1s2
This the result
Several messages I found strange here
- NO WRITE – how can that be? If I am trying to fix it how can it be no write?
- ok, it found a bad block at 137228189184 but at end it says the disk is OK
- what is block 26023808 NO MATCH?
- at end it says fsmodified = 0??? No modification performed?
I don't understand this. Have fsck_hfs fixed my disk? I by fixed I mean mark the block as unusable or reformatted it or whatever?
Thanks
Best Answer
The command you have given includes the "-l" option, which means to perform a "test-only check" and that "no repairs can be made". Essentially this means that it won't write to the file system, which explains your questions 1 and 4.
Regarding questions 2 and 3: The disk as such might be "OK" (i.e. usable) from the point of view of the filesystem even though a single bad block has been detected. As you have specified the "-S" option, fsck_hfs will attempt to match the bad block to a file name - it found not match. This could indicate that the bad block does not affect any of your files.
Consider replacing the drive when you start having bad blocks.