On my hard drive I have a largish unused partition that I would like to use.  Trouble is, it's an old Windows partition and I'd prefer to make it a proper Linux partition (I intend using it via LVM if that makes a difference).So what I'd like to do is re-jig the partition type and reformat it then add it to my already-existing LVM group.But what I'd really like to do is do this from within my existing Linux distribution running on the same drive.  I'd rather not have to go through the hassle of making/finding a live CD.So to be clear: the partition that I want to change is not mounted, but is on the same drive as my Linux distribution.  Is there a partitioning tool that will do that, and do it safely?
Can I change an unmounted partition's type from another partition on the drive?
partition
You use your favorite partition tool (fdisk, cfdisk, parted) in order to change the partition ID.You make the partition a valid LVM partition with pvcreate.You make the new PV available with vgcreate or vgextend.Not complicated at all. The worst case would be that you need partprobe or a reboot for LVM to recognize the new partition but probably LVM does not give much about the ID anyway.Changing the ID of an (in that moment and during booting) unused partition is in general a safe operation (for the running Linux; may badly affect other installed OSs though).