recovery after power outage

Jerry McAllister jerrymc at
Tue Feb 6 17:54:41 UTC 2007

On Tue, Feb 06, 2007 at 11:54:17AM -0500, Marty Landman wrote:

> My fbsd 6.0 box is having filesystem problems on boot since a blackout
> yesterday. Here's a synopsis:
> /dev/ad0s1a: clean
> ...repeats for ad0s1f & e
> then reports error=40<UNCORRECTABLE> for ad1 (twice) and reports an
> unexpected inconsistency for my ad1s1c device which is the primary slave hd.
> Tells me to run fsck manually and asks which shell I want. Maybe this is my
> fault for not partitioning appropriately, can't get to many commands
> including fsck guess it's because of the fs problems.
> How can I try and recover from this?

Well, do as it says - choose a shell and run fsck manually.
Probably you want the default shell = /bin/sh.
The output says ad0s1a is clean, so your fsck should be available.
Just run /sbin/fsck /dev/ad1s1c.   Actually that would be a somewhat
unusual address - what they call a 'dangerously dedicated' disk.
But I think fsck should be able to work through it.

You will probably have to sit there and answer 'y' to a bunch of
prompts or do fsck -y /dev/ad1s1c to force a y to everything.
The fsck that runs at boot pops out and stops the boot if it
runs in to anything it is scared to assume it will fix.   But in
most cases, there isn't anything you can do but answer 'y' anyway.
If that causes something to be lost, you probably wouldn't be able
to recover it anyway.   

When the manual fsck-s all finish - which can take a long time,
then reboot and see what happens.  It should come all the way up.

It the manual fscks don't work, then you may have to try some
extreme tactics to recover things on that partition or abandon

If you end up rebuilding the drive, then the next time make a
FreeBSD slice and then make a partition within that slice to
avoid that 'dangerously dedicated' config.

Good luck,


> Marty
> -- 
> Web Installed Formmail -
> Webmaster's BBS -
> _______________________________________________
> freebsd-questions at mailing list
> To unsubscribe, send any mail to "freebsd-questions-unsubscribe at"

More information about the freebsd-questions mailing list