On Tue, Mar 30, 2004 at 12:26:51PM +0200, Roberto Nunnari wrote: > hello. > > What does the auto argument mean? > > # bsdlabel -w /dev/amrd1 auto
Hmmm... Interesting. It seems that the description of 'auto' has vanished from the bsdlabel(8) man page, although it is present in the disklabel(8) man page from 4.x (disklabel was renamed bsdlabel between 4.x and 5.x): http://www.freebsd.org/cgi/man.cgi?query=disklabel&apropos=0&sektion=0&manpath=FreeBSD+4.9-stable&format=html According to disklabel(8), 'auto' means that {disk,bsd}label should try and create a "virgin" disklabel on the slice -- that (if I remember correctly) is essentially a 'c' partition spanning the whole slice, and nothing else. bsdlabel(8) either works the same way, or it will search for an entry marked 'auto' in disktab(5) -- see /etc/disktab -- and there is no such entry in the default /etc/disktab. Assuming bsdlabel(8) still works the same way as disklabel(8): note that the auto behaviour doesn't work on all media -- only those where {disk,bsd}label can find the parameters it needs without having to read the thing it's labelling directly. However, that includes all SCSI or IDE hard drives, vnodes and regular files. > Is it possible that the command above configures amrd1 > as the default boot partition and modifies amrd0 not the > be the active? And even modifies the partition table on > amrd0 so that it starts at sect 0 instead of sect 63 as before? No. bsdlabel(8) is all about BSD partitioning -- the final 'a' in a device name like /dev/amr1s1a It's fdisk(8) that sets /slices/ (the 's1' part in the device name) as bootable/non-bootable by altering the master boot record (MBR) on the drive (the 'amr1' part of the device name). If you're using fdisk(8) on a different drive to the one you usually boot from, then it won't be able to affect the usual booting process in the way you are asking about. If you used fdisk(8) to turn of the bootable flag on all slices on your boot drive, then yes, there would be an effect. However, I'm sure you would remember doing something like that. It's easy to reverse if you did -- just use fdisk(8) again. Cheers, Matthew -- Dr Matthew J Seaman MA, D.Phil. 26 The Paddocks Savill Way PGP: http://www.infracaninophile.co.uk/pgpkey Marlow Tel: +44 1628 476614 Bucks., SL7 1TH UK
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