I have an iBook Dual USB 700 1GB/40GB running OS X.2.1. I am having
problems with the drive. Periodically, the machine will start to give
me errors about the hard-drive being full and being unable to write to
it, despite having 3GB+ free. When I reboot the machine, any open file
(i.e., preferences, bookmarks) is gone. This is a giant PITA.

I have run Apple's Disk Utility and fsck (and fsck_hfs), both locally
and from another machine with the iBook in Target Disk mode and
connected via FireWire. Each time, the utilities report five
"Overlapped extent allocation" errors. The utilities report success in
repairing these errors, but if I run them subsequently, they still
show up.

I have decided to hunt down and manually delete the five offending
files (if necessary, I can recover them from a backup). I don't want
to do the "smart" thing and reformat, reinstall and recover, since
that's a two-day project and I'm supposed to be on vacation, but I'm
open to other suggestions.

In order to accomplish this feat, I will need to translate the files
as identified in fsck's output (i.e., "file 2596988d") to filenames
(i.e. /Users/foo/bar/foo.txt). Can you help me accomplish this trick
or suggest a better avenue?

Here is the output from fsck_hfs; I get identical output from fsck.

bash-2.05a$ sudo fsck_hfs /dev/disk2s10 
** /dev/rdisk2s10
** Checking HFS Plus volume.
** Checking Extents Overflow file.
** Checking Catalog file.
   Overlapped extent allocation (file 2596988d)
   Overlapped extent allocation (file 2596987d)
   Overlapped extent allocation (file 2596986d)
   Overlapped extent allocation (file 2596984d)
   Overlapped extent allocation (file 2596982d)
** Checking multi-linked files.
** Checking Catalog hierarchy.
** Checking volume bitmap.
** Checking volume information.
** Repairing volume.

Thanks!

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Clarification of Question by doctorow-ga on 26 Dec 2002 16:34 PST

Another thing I've tried is "clri" to try to manually delete the
inodes in question. This does not work. Here's some output:

bash-2.05a$ su
Password:
[Cory-Doctorows-Computer:/Users/doctorow] doctorow# clri
/dev/rdisk2s10 2596988d
clri: /dev/rdisk2s10: superblock magic number 0xffffffff, not 0x11954

[Hrm -- that's a cryptic error! Oh well, let's fsck it again and see
if that inode still shows up in the overlapped allocation list]

bash-2.05a$ sudo fsck_hfs /dev/disk2s10 
Password:
** /dev/rdisk2s10
** Checking HFS Plus volume.
** Checking Extents Overflow file.
** Checking Catalog file.
   Overlapped extent allocation (file 2596988d)
   Overlapped extent allocation (file 2596987d)
   Overlapped extent allocation (file 2596986d)
   Overlapped extent allocation (file 2596984d)
   Overlapped extent allocation (file 2596982d)
** Checking multi-linked files.
** Checking Catalog hierarchy.
^Cbash-2.05a$ 

[crap!]

---

Clarification of Question by doctorow-ga on 26 Dec 2002 18:04 PST

Also, I got the OS wrong -- it's not OS X.2.1, it's OS X.2.3

---

Clarification of Question by doctorow-ga on 26 Dec 2002 18:08 PST

Another thing:

I tried running fsck_hfs with the -p flag set. The first time it ran,
it reported the same "Overlapped extent allocation" errors. The second
time, it exited cleanly, without any errors reported. However,
fsck_hfs without the -p flag still reports the "Overlapped extent
allocation" errors.

Hi, 

Sorry to ruin your vaction, but the Overlapped extent allocation error
is generally caused by a physical problem with the hard drive itself,
and finding those files and deleting them won't fix your problem. The
fsck is just spitting out file names where the problem is happening.
Removing them will just cause the program to spit out something else.

Yes, it's is definitly a PITA, but at least it is not a PEBTKATC
error. The only way to determine this and what the Support folks are
going to tell you is to back up your files to an external drive (if
you have one) and reinstall the OS from scratch. Anything else at this
point is just going to ruin your vaction even more. The other option
is to skip that step, tell the Support folks you did it and have them
give you a new drive, because that's what is probably going to happen
anyway.

Sorry to be the bearer of bad-tiddings on the new year cusp.

Thanks, 

webadept-ga

I was able to find you a little more information on your problem:
other than just 'reformat and reinstall'.. Take a look at this thread
on Google Groups:
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&threadm=3833661F.8B8DA208%40earthlink.net&rnum=8&prev=/groups%3Fq%3D%2522Overlapped%2Bextent%2Ballocation%2522%26hl%3Den%26lr%3D%26ie%3DUTF-8%26selm%3D3833661F.8B8DA208%2540earthlink.net%26rnum%3D8

There are recommendations of a few different software programs that
might solve your problem -- without a reboot.. It's worth a shot
anyways.

Legolas-ga