> Sent: Saturday, September 22, 2018 at 11:39 AM > From: "Martin Husemann" <mar...@duskware.de> > To: "Rocky Hotas" <rockyho...@post.com> > Cc: "NetBSD Users Mailing List" <netbsd-users@netbsd.org> > Subject: Re: BSD disklabel partition letters in NetBSD > > It is actually quite simple (with a few twists, muahahah :-}):
I guessed it :). > You can check with "sysctl kern.rawpartition", it is 3 on these architectures. Ok, thanks! > Then there are architectures that traditionally required an MBR > partitioning scheme (usually to cooperate with ancient other OSes), so > you have to use fdisk before disklabel to partition a disk. So, the distinction between systems that only reserve partition "c" and those who also reserve partition "d" is the necessity to use MBR. I wonder if in those systems one can install BSD disklabel to replace MBR (without caring about incompatibilities with other OSs): and, if yes, what would be the use of "c" and "d" when MBR doesn't exist at all. In other words: with amd64, if it is possible to use the whole disk and to install BSD disklabel as the only partition table, what would happen? > All other partition letters are free for arbitrary use. Very common (but not > mandatory) is "a" as root partition, and "b" as swap. Ok! > For the number of disklabel partitions: this depends on the architecture - > where the disklabel structure is shared itself with other OSes (say on Sun > machines) we can not arbitrarily change it. On some others (e.g. VAX) > there are size limitations due to boot code placement (or similar). Like for `rawdisk', is there any other sysctl parameter with the number of available partitions in the current system? > Now, of course, this all became mood on most modern machines with the move > to GPT, and this is good. As you probably know, we use full devices for > these (dk* and rdk*), so no limiting alphabet nor reserved letters. Despite vaguely knowing that GPT is replacing MBR and similar, I never installed NetBSD with GPT, so I didn't know this. > Martin Thank you! Rocky