OpenBSD: Destroy a Softraid Partition
Booting an OpenBSD's installation media and trying to remove previously created
softraid partitions may end up with the following error:
disklabel: ioctl DIOCWDINFO: Open partition would move or shrink disklabel: unable to write label
Here is how to resolve this issue...
The problem is that the device nodes (in the
/dev directory) are not created automatically by default after the installation media boots.
Here is how to create the device nodes manually:
$ cd /dev $ sh MAKEDEV sd0 $ sh MAKEDEV sd1
...continue for as many nodes as necessary.
Now, it is possible to detach an
softraid0 partition (will destroy data):
$ bioctl -d sdX
And finally, to edit the
disklabel of disk
sdY (will destroy data):
$ disklabel -E sdY d a d b
... and continue for as many partitions as necessary.