ERROR: Unable to write data to disk idad1

[Didier WIROTH]

Yes, the error occurs when using disklabel 

> I tried to add a partition (with /stand/sysinstall) to idad1s1. This 
> should become idad1s1f but when I try to "w"rite the changes to disk 
> the following error appears: "ERROR: Unable to write data to disk idad1!"
> Unfortunately I'm not able to add any new partitions, why, what's wrong?

GEOM may be preventing you from modifying the disklabel because you have
filesystems mounted etc.

Does the error occur when using 'disklabel'?