From owner-freebsd-hackers Sat May 27 05:13:49 1995 Return-Path: hackers-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.10/8.6.6) id FAA21470 for hackers-outgoing; Sat, 27 May 1995 05:13:49 -0700 Received: from eikon.regent.e-technik.tu-muenchen.de (root@eikon.regent.e-technik.tu-muenchen.de [129.187.42.3]) by freefall.cdrom.com (8.6.10/8.6.6) with SMTP id FAA21464 for ; Sat, 27 May 1995 05:13:44 -0700 Received: from vector.eikon.e-technik.tu-muenchen.de ([129.187.142.36]) by eikon.regent.e-technik.tu-muenchen.de with SMTP id <43213>; Sat, 27 May 1995 14:13:21 +0200 Received: (from jhs@localhost) by vector.eikon.e-technik.tu-muenchen.de (8.6.11/8.6.9) id XAA10023; Fri, 26 May 1995 23:17:52 +0200 Date: Fri, 26 May 1995 23:17:52 +0200 From: Julian Howard Stacey Message-Id: <199505262117.XAA10023@vector.eikon.e-technik.tu-muenchen.de> To: "Rodney W. Grimes" cc: hackers@FreeBSD.org Subject: Re: fdisk problem - any suggestions In-reply-to: Your message of "Thu, 25 May 1995 20:52:13 +0200." <199505251852.LAA01120@gndrsh.aac.dev.com> Sender: hackers-owner@FreeBSD.org Precedence: bulk -------- Hi Rod, (CC hackers) Re. no boot blocks on my system ... > > Hi folks, > > I've painted myself into a corner, & would welcome suggestions how to > > get out :-) > > > > I used to have a 50M DOS partition on my root partition, but it was corrupt, > > & fdisk didnt understand it, so i reinstalled the drive, & reduced the 50M > > to 20M too :-), > > I used DOS fdisk to install a C:, then Freebsd fdisk to & disklabel > > using both rsd0c & rsd0d as I recall, > > (I suspect maybe i should have not done 0d) .. > > Now I have a DOS partition I can mount under Freebsd, > > I can even see the C: dos thing if i boot from a dos flopppy, > > but if i try to boot off the hard disc it always runs freebsd, > > regardless of whether I mark freebsd or dos as active with fdisk. > > > > Only thing I can think of now is to install that os-bs thing (from wherever) > > > > Any other suggestions ? > > fdisk/mbr perhaps, you may still have a FreeBSD boot strap in block 0-15 of > the drive. Thanks, I thought I'd zapped the MBR, (though had forgotten the acronym), After I'd realised you meant the DOS command fdisk, I tried it, it seemed to work (unfortunately neither my MS DOS 5 or MS DOS 3 manuals (`3' came with Toshiba T1100+ years ago) seems to list the /mbr syntax, so I'm working blindfolded ) after using dos sys command too, now the 486 boots OK with DOS 20M in slice 0, _However_ FreeBSD can no longer can auto boot ! So I've used the SNAP 95 02 10 rescue flop to install a boot manager (`B' command in some menu ) - which looks cute, but doesnt take me too far. I suspected my /usr/mdec stuff was screwed, so I `refreshed' it with CD-ROM 2.0 stuff (quicker than reading source & trying to figure the dd offsets to read off boot flop & write to winchester). I changed my geometry from :ns#70: :nt#15: :nc#1356: :se#512: to :ns#140: :nt#15: :nc#678: :se#512: to squeeze under the 1024 cyl limit. I used disklabel -B & fdisk again, both on both rsd0c & 0d still no good on reboot, The boot manager just tries for F4 & silently returns. BTW I notice if disklabel is run, it zaps the fdisk display: namely the DOS slice 0 dissapears, & the Slice 3 FreeBSD becomes start 0 size 50000 It's only the boot sector(s) that are missing, as I can boot off the SNAP floppy, & then continue with sd(0,a)/kernel (which is how I'm booting the system that's doing this mail). Further suggestions welcome please :-) ( I suspect I'll have to resort to `dd' (anyone remember the incantation)) Julian S