Date: Thu, 13 Mar 2008 03:32:37 +0100 From: "Snow Mountains" <snow.mountains.4@gmail.com> To: "Josh Paetzel" <josh@tcbug.org> Cc: freebsd-questions@freebsd.org Subject: Re: no ad1s3a,b,d... on ad1s3 after bsdlabel Message-ID: <3cf9f8920803121932j32caaa79i407dbab8106b3dd8@mail.gmail.com> In-Reply-To: <200803121429.14760.josh@tcbug.org> References: <3cf9f8920803101018i573a5c26l986b9508495fcd5a@mail.gmail.com> <444pbcdvwj.fsf@be-well.ilk.org> <3cf9f8920803120530k7f6420bfl5aa203864c058c90@mail.gmail.com> <200803121429.14760.josh@tcbug.org>
next in thread | previous in thread | raw e-mail | index | archive | help
2008/3/12, Josh Paetzel <josh@tcbug.org>: > On Wednesday 12 March 2008 07:30:34 am Snow Mountains wrote: > > 2008/3/12, Lowell Gilbert <freebsd-questions-local@be-well.ilk.org>: > > > "Snow Mountains" <snow.mountains.4@gmail.com> writes: > > > > I try to understand bsdlabel. > > > > I have former fat slice (ad1s3) on my disk and I want to make several > > > > BSD partitions on it. I did this: > > > > > > > > # dd if=/dev/zero of=/dev/ad1s3 bs=1k count=1024 > > > > 1024+0 records in > > > > 1024+0 records out > > > > 1048576 bytes transferred in 0.318986 secs (3287217 bytes/sec) > > > > # bsdlabel -w ad1s3 > > > > # bsdlabel -e ad1s3 > > > > (edit) > > > > # bsdlabel ad1s3 > > > > # /dev/ad1s3: > > > > 8 partitions: > > > > # size offset fstype [fsize bsize bps/cpg] > > > > a: 10000000 16 4.2BSD 0 0 0 > > > > b: 10000000 10000016 4.2BSD 0 0 0 > > > > c: 47616660 0 unused 0 0 # "raw" part, > > > > don't edit d: 27616644 20000016 4.2BSD 0 0 0 > > > > # newfs -U /dev/ad1s3a > > > > newfs: /dev/ad1s3a: could not find special device > > > > # ls /dev/ad1s3* > > > > /dev/ad1s3 > > > > # > > > > > > > > What I miss because I don't have ad1s3a,b,d? > > > > If repeat same procedure on disk (big file) mounted as /dev/md0, a see > > > > /dev/md0,a,b,d,e... after this group of commands. > > > > > > On what version of FreeBSD? > > > > This happens on: > > > > # uname -r > > 6.2-RELEASE-p11 > > > > SergiM > > > Did you delete and recreate the slice or is it still marked as FAT when you do > fdisk /dev/ad1 Josh, you are right! No, I did not do it. It was still marked as FAT. I thought that it is enough to overwrite first 1M of slice with zeros. I entered sysinstall and just changed slice's type with T. That was enough. Then, fresh bsdlabel appeared on it. After editing, I now have all BSD partitions (a,b,d...) mountable. However, here handbook is not precise, I think. Please see this: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/disks-adding.html I deduced from it that fdisk is necessary only for dedicated and new disks (fdisk -BI da1 #Initialize your new disk). > If it's still a FAT/DOS slice you might try deleting and recreating it as a > native FreeBSD slice, I'm not entirely sure putting a bsdlabel on a FAT slice > is going to do the right thing (although I could be wrong here) > It seems that you are right. But this still confuses me: # dd if=/dev/zero of=/home/minidisk.bin bs=1k count=100000 ......... # mdconfig -a -t vnode -f /home/minidisk.bin -u 2 # ls /dev/md2* /dev/md2 # bsdlabel -w md2 # ls /dev/md2* /dev/md2 /dev/md2a /dev/md2c # bsdlabel -e md2 .......... # ls /dev/md2* /dev/md2 /dev/md2b /dev/md2d /dev/md2a /dev/md2c /dev/md2e and then # fdisk /dev/md2 ******* Working on device /dev/md2 ******* ................ The data for partition 1 is: sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD) start 63, size 192717 (94 Meg), flag 80 (active) beg: cyl 0/ head 1/ sector 1; end: cyl 11/ head 254/ sector 63 The data for partition 2 is: <UNUSED> The data for partition 3 is: <UNUSED> The data for partition 4 is: <UNUSED> So bsdlabel was enough in this case. Why is this different from real hard disk? And one more question: is disk geometry data somehow written in fdisk W (write) actions? I mean, is it possible to spoil something on existing FreeBSD slices (which contain data) if I set wrong geometry for entire drive when I edit something in fdisk editor? Thank you very much SergiM
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3cf9f8920803121932j32caaa79i407dbab8106b3dd8>