Date: Fri, 12 Jan 1996 13:48:53 -0700 (MST) From: Terry Lambert <terry@lambert.org> To: hlew@genome.Stanford.EDU (Howard Lew) Cc: questions@FreeBSD.org Subject: Re: Ontrack DM & FreeBSD 2.1R Message-ID: <199601122048.NAA20633@phaeton.artisoft.com> In-Reply-To: <Pine.SUN.3.91.960111173539.2106J-100000@vegemite.Stanford.EDU> from "Howard Lew" at Jan 11, 96 05:36:21 pm
next in thread | previous in thread | raw e-mail | index | archive | help
> Here's a little more info about Ontrack DM (version 7 I believe) and > FreeBSD > 2.1R. > > My configuration: > wd0 is Windows 95 only. > wd1 is FreeBSD only. > > During the installation of FreeBSD 2.1R to wd1, I carefully chose none for > the mbr or multi-boot code, but FreeBSD 2.1R still does something to wd0 > which makes the Win95 hard drive unbootable. > > How to recover wd0.... Need to rewrite the mbr using Ontrack DM after > booting from a DOS floppy. After that, need to reboot from a DOS disk > one more time to set the DOS/WIN95 partition active on wd0 with fdisk. > After that, everything is back to normal. > > > 3 Questions: > > 1) Is there any chance that a future version of FreeBSD will truly > not touch wd0? The current version doesn't, unless you tell it to. The problem is you told it to, but you didn't know it. > 2) And can fbsdboot.exe be made as an option to boot a kernel from wd1 > instead of wd0? Or am I just missing the syntax somewhere? Yes. You will have to recompile it (I believe -- it may have options now that it didn't used to have). > 3) Will FreeBSD 2.1R soon notice my Teac 4X Model 55A cdrom drive? Dunno. The nitty-gritty on what is happening: Because you are booting the FreeBSD boot disk, you aren't loading the OnTrack code. The OnTrack code operates by redirecting INT 13 after loading an INT 13 to LBA and geometry traslantion TSR. When you tell BSD to install its boot manager, it goes to the boot device (wd0) and rewrites the boot code, assuming that the valid partition table entry there (which is the Ontrack relocation entry for the DOS partition table) is the one it wants to write. Basically, because you installed onto the second disk, BSD became confused. In reality, you could call this a BSD bug, because BS should see the OnTrack partition ID on the wd0 disk and realize that the MBR it is supposed to write to enable the boot selector is actually 64 sectors further in on the disk. The workaround is to use the DOS version of the OS-BS install from a DOS prompt after booting DOS from wd0 (if you are booting Windows95, you will need to pick the "reboot to DOS prompt" option from the "Shutdown" on the Windows95 "Start" menu or the install will be prevented, since they guard their boot track as a virus safeguard). This means you should *NOT* install the boot selector when you install BSD on the second drive, since the boot selector must always be written to the boot drive's boot sector (and that's not where BSD thinks it is in the current release of the install tools). Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199601122048.NAA20633>