While no expert, I would advise against running the kernel directly. The loader allows you to boot in single user which may come handy at times.
On 24 Nov 2012, at 18:08, "Lucas B. Cohen" <[email protected]> wrote: > Hi Ralf, > > On 2012.11.24 17:06, Ralf Mardorf wrote: >> Perhaps later today I'll install 9.0 amd64. If possible I'll keep my >> Linux GRUB legacy. Can I use my menu.lst [1] and add a chainloader or >> something similar to boot FreeBSD from /dev/sda1? > I don't know if GRUB v1 allows that, on a multiboot system I use GRUB 2 > to either load FreeBSD's loader(8) : > > menuentry "FreeBSD (Loader)" { > insmod part_bsd > set root='hd0,msdos2,bsd1' > echo "Loading FreeBSD loader" > kfreebsd /boot/loader > echo "Starting FreeBSD loader" > } > > or to run its kernel directly, after having passed it optional device hints: > > menuentry "FreeBSD (Direct Boot)" { > insmod ufs2 > set root='hd0,msdos2,bsd1' > echo "Loading FreeBSD kernel" > kfreebsd /boot/kernel/kernel > echo "Loading FreeBSD environment" > kfreebsd_loadenv /boot/device.hints > set kfreebsd.vfs.root.mountfrom=ufs:/dev/ada0s2 > echo "Booting FreeBSD" > } > > I'm not saying it's impossible, but I'm unable to chainload to the > loader code on my system with this: > menuentry "FreeBSD (Chainload)" { > insmod chain > set root='hd0,msdos2' > chainloader +1 > } > > > >> FWIW I made backups of my HDD's MBRs. >> I wonder if the installer will overwrite the MBR? > Always a good thing to have backups. From what I've experienced and > read, 9.0-RELEASE's installer is not always predictable in that regard, > it's probably safer to assume it'll won't do what you want, and just > restore your MBR after the installation, to go back to using GRUB for > dual-booting. > > Here's the pitfall, though: the MBR also holds the partition table. So > make a fresh backup after you've created/reorganized the primary > partitions (slices) on your disk using a tool you're familiar with. > (Logical partitions and BSD partitions are stored differently, so they > will survive an MBR restore, provided it doesn't modify the primary > partition they're contained in.) > >> I also would like to know, if there's a way to recover the partition >> table, including a primary FreeBSD partition/slice, if this ever should >> get broken and there should be no backup of the partition table be >> available. > The partition table is held alongside the MBR, in the first logical > sector of your disk. Restoring one will restore the other. > For extra safety, you can save the output of partitioning tools like > fdisk or GNU parted expressed in sectors. > > Hope this helps, > > _______________________________________________ > [email protected] mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "[email protected]" _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[email protected]"
