ncheck on a vxfs filesystem

[Randy Rayfield]

When running the ncheck command and sorting by the sector, there are some sectors on the disk that are missing. Are these sectors that have been marked as bad blocks?

[Stephen Keane]

Not necessarily, you've also got the boot sector, raw sectors used by swap etc, superblocks, empty sectors and i-node tables that won't show up as being used by files.

[Randy Rayfield]

Inodes are marked, free sectors are marked, extent_maps are marked. There are just the occasional couple of blocks that are missing from the sequential list of blocks.

[Stephen Keane]

Sorry, caught me BC (before coffee), which ncheck command are you running? The only one I have is

ncheck(1m) - generate a list of path names from inode numbers

How are you displaying sector information? Unless you are using 'pvdisplay -v' or something similar.

[Randy Rayfield]

ncheck -F vxfs -o block=- /dev/vg01/lvol29 | sort -n +5

You can see all the inodes, directory structures, free, Etc. However, occasionally there are a few blocks that are missing from the sequential list. I am assuming that these are the ones marked as bad.

[Stephen Keane]

you could always try the flag

-o block=X

Where X is one of your missing block numbers, and see what happens?

I don't get any missing when I run the command on my server. Have you run a fsck on /dev/vg01/lvol29 recently?

Do you have your LV option set to strict/contiguous and bad block allocation switched on?