On Fri, Mar 30, 2007 at 08:07:23AM +1000, Antony Mawer wrote: > On 29/03/2007 6:41 AM, Kris Kennaway wrote: > >On Wed, Mar 28, 2007 at 05:26:49PM -0300, Marc G. Fournier wrote: > >>Just bought a new WD SATA drive: WDC WD5000YS-01MPB1 09.02E09 > >> > >>Tried to disklabel it, and it gives me all kinds of warnings when I look > >>at it after running the disklabel: > >> > >> > >>ganymede# bsdlabel -w ad4s1 auto > >>ganymede# bsdlabel ad4s1c > >># /dev/ad4s1c: > >>8 partitions: > >># size offset fstype [fsize bsize bps/cpg] > >> a: 976767986 79 unused 0 0 > >> c: 976768002 63 unused 0 0 # "raw" part, > >> don't edit > >>partition a: partition extends past end of unit > >>partition c: partition extends past end of unit > >>bsdlabel: partition c doesn't start at 0! > >>bsdlabel: An incorrect partition c may cause problems for standard system > >>utilities > >> > >>Even if I try to use /stand/sysinstall to do the fdisk, the end result > >>has 'issues' ... > >> > >>So, what is the generally accepted method of label'ng a new drive? :( > > > >I learned a useful trick the other day: you can use abbreviations like > >"1g", also '*' to mean "automatically calculate". See the manpage. > > This timely thread came as I was experimenting with disklabel, and I > noticed in the man page it says this: > > > offset The offset of the start of the partition from the beginning of > > the drive in sectors, or * to have bsdlabel calculate the > > correct > > offset to use (the end of the previous partition plus one, > > ignor- > > ing partition `c'. For partition `c', * will be interpreted as > > an offset of 0. The first partition should start at offset 16, > > because the first 16 sectors are reserved for metadata. > > When I tried using "16" as the offset for my 'a' partition, I could no > longer user "*" on my last partition to make it auto-size... disklabel > then sized the partition so it went past the end of the disk. Presumably > it's not taking into account the starting offset when it does this (gm0 > is a 3gb gmirror device, with a single slice created on it using fdisk): > > $ bsdlabel -R /dev/mirror/gm0s1 /dev/stdin > 8 partitions: > a: 2097152 16 4.2BSD > b: 102400 * swap > c: * 0 unused > d: 102400 * 4.2BSD > e: * * 4.2BSD > partition e: partition extends past end of unit > > However if I change the 'a' partition offset to 'e', it works: > > $ bsdlabel -R /dev/mirror/gm0s1 /dev/stdin > 8 partitions: > a: 2097152 0 4.2BSD > b: 102400 * swap > c: * 0 unused > d: 102400 * 4.2BSD > e: * * 4.2BSD > $ disklabel /dev/mirror/gm0s1 > # /dev/mirror/gm0s1: > 8 partitions: > # size offset fstype [fsize bsize bps/cpg] > a: 2097152 0 4.2BSD 0 0 0 > b: 102400 2097152 swap > c: 6281352 0 unused 0 0 # "raw" > d: 102400 2199552 4.2BSD 0 0 0 > e: 3979400 2301952 4.2BSD 0 0 0 > > Is it important to use 16 as the offset still, or is this a historical > piece of information that is no longer relevant? Or is this is a bug in > disklabel that should be fixed?
As I indicated in another post in this thread, it appears to be vestigial. I have never used it for a bsdlabel(disklabel) being done on a slice - since 1998. There seems to be a lot of left over stuff in the documentation and man pages for fdisk and bsdlabel (and disk formatting, partitioning and booting in general). Someone made a pass at cleaning them up about 6 years ago and that helped, but it could stand to be done some more. If I felt knowledgeable enough, I would take a whack at it. But there are too many holes (not wholes) in my knowledge. I would guess from posts in the list that a lot of people are in that position - knowing a bunch of it, but not quite enough to be authoratative about it. I have written several long replies to questions on this list that could be the basis for FAQs or HowTo-s, but they still leave a lot of things out and generalize or slide over lots of other things for the sake of convenience, avoiding confusing a newbie and/or not being sure about all the details. ////jerry > > --Antony > _______________________________________________ > email@example.com mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "[EMAIL PROTECTED]" _______________________________________________ firstname.lastname@example.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"