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Xref: sserve comp.os.386bsd.development:2191 comp.unix.pc-clone.32bit:6396 comp.os.linux.development:9571 Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!lll-winken.llnl.gov!fastrac.llnl.gov!s1.gov!overload.lbl.gov!agate!howland.reston.ans.net!EU.net!Germany.EU.net!lemis!grog From: grog@lemis.uucp (Greg Lehey) Newsgroups: comp.os.386bsd.development,comp.unix.pc-clone.32bit,comp.os.linux.development Subject: Booting from CD-ROM (was: 386BSD 1.0 - Stop it, please...) Message-ID: <3113@adagio.lemis.uucp> Date: 18 May 94 06:45:42 GMT References: <2r6c10$kis@news.cs.tu-berlin.de> <jlemonCpwnBr.CGn@netcom.com> Followup-To: comp.os.386bsd.development Organization: LEMIS, 36325 Feldatal, Germany Lines: 64 In article <jlemonCpwnBr.CGn@netcom.com> jlemon@netcom.com (Jonathan Lemon) writes: >In article <2r6c10$kis@news.cs.tu-berlin.de>, >Lars Grupe <lunde@cs.tu-berlin.de> wrote: >> >>A word to some others: Do you really find it interesting whether an >>OS that has not been seen by anyone here does boot off a CD-ROM? > >Nope. > >If I could stick a CD-ROM in the drive and turn the machine on, then >possibly I would be interested. If I have to go and: > 1) muck with my SCSI settings (where did my manuals go?) > 2) reboot the machine after saving the changes > 3) remember to re-change the settings for normal operation after > finally booting from the CD > >then I fail to see the point. Sure, it may be a neat hack, but it's not >easier than putting in a floppy. If it's not an improvement over the current >status quo, then why should I care? What little information has come out of this flood of messages suggests: 1. It's possible with an Adaptec 1540x. 2. It's not possible with CD-ROMs with their own host adapters. 3. You may need to do special things to your aha controller to boot from the CD-ROM. In addition, the question arises: once I have my aha set up to boot from CD-ROM, how do I get it to boot from hard disk? This is independent of the question of target addresses: at some point, you need to interface with the PC BIOS, which usually allows you to choose which permutation of A: and C: drives you want to try to boot from. This suggests to me that once you have set up your system to boot from CD, you need to change it again to boot from hard disk. If this is the case, than it's a tradeoff between inserting a boot diskette and rebuilding your computer. Which would you choose? There is (theoretically) a simpler way: a universal boot diskette. This should be intelligent enough to boot from all better-known devices, including specifically: - SCSI CD-ROM - proprietary interface CD-ROMs (e.g. Mitsumi) - SCSI tape - QIC-02 tape - Floppy tape - Just for the fun of it, hard disk All it needs to do for any of these devices is to read in a second-level bootstrap from the device, and leave the remaining processing to the second-level bootstrap. As such, it would be OS-independent. I believe that the Linux LILO does something similar on a disk partition basis, and obviously the code is there for most of the devices I have mentioned. Is anybody interested in putting together such a diskette? -- --------------------------------------------- Greg Lehey | Tel: +49-6637-1488 LEMIS, Schellnhausen 2, | Fax: +49-6637-1489 36325 Feldatal, Germany | Mail: grog@lemis.de