Can't *write* to a hard disk, problem related to GEOM(4)?

[Jon Noack]

On 4/15/2004 1:46 PM, Julien Gabel wrote:
> Hello,
> 
> I post to current@, since the problem *seems* to be related to GEOM.
> 
> The first thread for this subject begin from question@, you can read it
> here:
>  http://lists.freebsd.org/mailman/htdig/freebsd-questions/2004-April/\
>  thread.html#43212
> 
> I can resume my problem like that:
>  - My OS release is FreeBSD 5.2.1-RELEASE-p4;
>  - The disk is a 120Go/8Mo from Maxtor (UDMA133);
>  - What dmesg(8) says about it:
>     # grep ad10 /var/run/dmesg.boot
>     GEOM: create disk ad10 dp=0xc6ab2660
>     ad10: 117246MB <Maxtor 6Y120P0> [238216/16/63] at ata5-master UDMA133
>  - But when I tried to create a slice on it, I get:
>     # fdisk -BI ad10
>     ******* Working on device /dev/ad10 *******
>     fdisk: can't write fdisk partition table: Operation not permitted

Perhaps this is a silly question given the discussion of GEOM (of which 
I know nothing), but is it necessary to run this command in single-user 
mode?

Jon Noack