Do you need to dismount /usr to dump it?

Jerry McAllister jerrymc at
Wed Nov 10 08:28:02 PST 2004

> If I boot to single-user mode (reboot, hit space, do boot -s) and dump /usr 
> to a file, I get read errors on a couple of blocks.
> Running fsck -y (also in single user of course) did not show a problem, but 
> it did not clear up the errors when I tried the dump again.
> I thought it was safe to dump /usr in single-user mode. Will I need to boot 
> off a CD or try another trick to get a clean dump of /usr? Or perhaps I am 
> not using the right fsck options?
> the dump command I used is:
> dump 0af /someotherplace/filename.dump /usr
> This seemed to work fine for / and my other filesystems.

Your problem seems to be bad blocks in the /usr file system.
That has nothing to do with dump.  It is a bad spot on the disk.
fsck will not fix that sort of thing.   If you can figure out
what files sit on the bad spots, you might be able to delete them
and then do your dump.   Then you should immediately replace the


> Thanks!
> - matt s.
> -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
> Matt Staroscik * KF6IYW * mstar at *
> "The combined weight of the horrors I have authored wrought would crush
> your carbon hearts into perfect diamonds of terror."
>                                          -- Leonid Kasparov Destroyovitch

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