Date: Fri, 1 Aug 1997 08:55:08 -0500 (CDT) From: "M. L. Dodson" <bdodson@beowulf.utmb.edu> To: questions@FreeBSD.ORG Subject: Re: NT4, FBSD, different disks and booting Message-ID: <199708011355.IAA03549@beowulf.utmb.edu>
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Sorry for the followup to my followup. Brain fade at the end of the day. > > Just to follow up with the final solution I settled on, here is one > way to at least avoid having to boot from a floppy. Thanks to several > people who responded with suggestions. Note that I reinstalled > NT and DOS 6.22 such that there is an initial DOS FAT file system > 100MB in size with the rest of the disk being NT using NTFS. I > have not tested this solution on a 100% NTFS IDE boot disk (although > I think it should work there). This is on FreeBSD 2.2.2 from the WC > CDROM and NT 4.0 Workstation. > > cd /usr/src/sys/i386/boot/biosboot and edit start.S to produce: > > diff start.S start.S.orig > 136a137 > > mov $0x81,%dl > Obviously, this does no one any good unless they are using 2.2.2RELEASE. Here is a generous context diff for someone using another version: *** start.S.orig Tue Jul 29 04:18:00 1997 --- start.S Tue Jul 29 04:22:09 1997 *************** *** 127,146 **** --- 127,147 ---- jmp load hd: /**** load sector 0 into the BOOTSEG ****/ data32 mov $0x0201, %eax xor %ebx, %ebx /* %bx = 0 */ data32 mov $0x0001, %ecx data32 andl $0xff, %edx + mov $0x81, %dl /*mov $0x0080, %edx*/ int $0x13 data32 jb read_error /* find the first 386BSD partition */ data32 mov $PARTSTART, %ebx data32 mov $NUMPART, %ecx Also, these URLs have pertinent discussions of the multiboot issue. http://www.devious/com/freebsd/ http://www.owlnet.rice.edu/~sedmison/directboot.html Thanks to jas@slugvine.demon.co.uk (John Stark) for pointing these out. Also, don't forget to read the FAQ entry on NT/FreeBSD booting. > make > cp boot.nohdr /msdos/bootsect.bsd # FAT partition is mounted on /msdos > > Reboot to DOS and edit boot.ini as described in the FAQ to make a > FreeBSD boot option entry > > ctrl-alt-del > > Select the FreeBSD entry at the NT boot prompt. > > At the FreeBSD boot prompt enter: > > 1:sd(0,a)kernel (just like you were booting from a floppy) > > FreeBSD comes up and finds its root partition correctly. If you do > not enter: > > 1:sd(0,a)kernel > > at the FreeBSD boot prompt, the kernel panics because it cannot find > its root partition (device probe works, though). > > Not elegant, but I don't have to walk around to the other side of > my desk to insert/remove a FreeBSD floppy each time I reboot to the > other OS. > > Of course, all the usual disclaimers about me not being responsible > if this incantation reformats your hard disk, etc. :) > > Bud Dodson > > > > > On Fri, 25 Jul 1997, M. L. Dodson wrote: > > > > > Mine is a quite common situation, I would think. Description: a > > > new PentiumPro, which, of course, comes with an IDE disk. Not > > > wanting to demean ;) FreeBSD by installing it on the IDE disk, I > > > installed FBSD on an external 4 GB SCSI (not "dangerously > > > dedicated", just the standard slice install). NT 4.0 workstation > > > is living on the whole IDE disk (I need to boot BT sometimes > > > to use Excel and Word). > > > > > > I went to the FAQ to see how to setup the NT bootmanager to > > > handle the dual boot, where I see that the recipe only works if > > > both are on the same disk. Aha, says I, I just need a customized > > > boot block. So I went to the biosboot directory where I compiled > > > a bootblock with BOOT_HD_BIAS=1, substituted boot1 (obtained after > > > the make) for the boot block normally acquired via dd in the recipe, > > > and still got a "no bootable partition" error, with no FBSD boot. > > > > > > Does anyone know how to handle this type of (likely quite common) > > > situation? Booting off a floppy is getting old fast. > > -- > M. L. Dodson bdodson@scms.utmb.edu > 409-772-2178 FAX: 409-772-1790 > -- M. L. Dodson bdodson@scms.utmb.edu 409-772-2178 FAX: 409-772-1790
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