format disk in bsd

[Nguyen Danh Hieu]

Hi everybody
I have about 20Gb unused space and  40Gb of  NTFS on my HDD an I want to
change them to ufs . But everytime when I tried with cfdisk-linux   or
sysinstall => configure => fdisk (as root )  it is said that I am not
allowed to write disk table (or something like "disk read only" )  But I am
root , why did it happen? someone show me solution plz?
Thank you.

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Nguyen Danh Hieu

Physics Faculty
Moscow State University