Can't *write* to a hard disk, not even a slice using fdisk(8).

Julien Gabel jpeg at
Tue Apr 13 06:56:31 PDT 2004

>>>> GEOM doesn't let you write to an active device, except if you set
>>>> kern.geom.debugflags=16

>>> Ok no problem, I changed it this way:
>>>  # sysctl kern.geom.debugflags=16
>>>  kern.geom.debugflags: 1 -> 16
>>> But it seems to change *absolutly nothing*... :(


>> Mmmhh... We're doing something wrong here I guess :o Are you 100% sure
>> that ad10 is not used by any open geom modules? What does dmesg say
>> about ar*?

> Well, I see that geom tastes ad10 and creates a slice class for it...
> However, if kern.geom.debugflags=16, you should still be able to touch
> the slice.
> If debugflags=16 I know of no reason why you shouldn't be able to
> partition de disk; sorry, I'm stumped :(

Ok, some news here. I can't be able to access/write to ad10 using fdisk
for example... under FreeBSD-5.x (OS version installed on the server).

But I gave a try to the CD "4.9-i386-mini.iso" and... I succeed to create
a slice on ad10 and even to partition and write some files on it!

So, what I can say here:
 - The disk seems not to be dead;
 - But after I had modify it under the 4.9 CDROM, I can't access it (fdisk,
   bsdlabel, etc.) under the installed and running OS on this machine:
   FreeBSD 5.2.1. :(

It seems that 'Joan' was in the right direction arguing to play with
"kern.geom.debugflags", but it didn't work for me. If someone has an
other idea with this new point in mind...

Thanks in advance,

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