Date: Tue, 12 Nov 2002 18:59:14 +0300 From: "Anton Vinokurov" <anton@inorg.chem.msu.ru> To: "Bruce M Simpson" <bms@spc.org> Cc: <freebsd-hackers@freebsd.org> Subject: Re: boot from USB ZIP or USB HDD Message-ID: <001801c28a64$7311e330$14d1d0c3@main.inorg.chem.msu.ru> References: <001101c28a5d$973304d0$14d1d0c3@main.inorg.chem.msu.ru> <20021112153812.GJ16068@spc.org>
next in thread | previous in thread | raw e-mail | index | archive | help
My motherboard (VIA Epia) support booting from USB-FDD, USB-ZIP, USB-HDD and USB-CDROM. I have no idea how it works and what the difference between all this methods. My USB flash device could be formatted as "bootable" under Windows as USB ZIP device, and when I set "boot from USB ZIP" in BIOS - all is fine, and I see "a:>" DOS prompt. But setting "USB HDD or USB HDD or USB CDROM" as boot device at BIOS fails - boot block cannot be found. The problem is that FreeBSD boot block (boot0, boot1 or boot2 - I don't know) assumed that booting is performed from HDD device, but it is untrue. Maybe I should use different boot blocks? Is it possible to boot FreeBSD form ZIP device (seen by BIOS as ZIP, not HDD or FDD)? I know that we have different boot block to boot from CD (/boot/cdboot) and maybe we should have something like /boot/zipboot? Anton L. Vinokurov, CCNA anton@inorg.chem.msu.ru NeTAMS Development Team > USB booting support is down to two things: BIOS and kernel support. > > If the BIOS can probe and boot from it in a similar way to how one might > boot from an El Torito CDROM, then the BIOS has done its bit. > > Going further, some BIOSes support making these devices visible to DOS, I > assume - I don't have any first hand experience of this. > > The problem here is that you won't even get as far as the loader *unless* > the BIOS is able to interpret the USB device as a hard disk drive. If the > BIOS emulates a fixed disk device in a traditional sense then standard > boot code will work fine. > > However, if its USB boot emulation doesn't extend to the BIOS > interrupts used by the standard FreeBSD boot sector, you won't even get > as far as the loader. > > Once the kernel has started to boot, it will need to have a disk driver which > can understand the disk it's booting from, otherwise it will fail to mount > root. > > I don't have time to do further research on this right now but I suggest > you contact your BIOS vendor for information, or research on their web site. > > BMS > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?001801c28a64$7311e330$14d1d0c3>