gpart and mbr give "no operating system" message at boot.
markham_breitbach at ssimicro.com
Fri Sep 7 19:31:07 UTC 2012
I am trying to partition a disk to be used as the primary boot disk for a FreeBSD 8.3
installation using gpart to install an MBR partition.
The system is an existing FreeBSD 5.2.1 system at a remote location (ie impossible to boot
from CD/netboot/etc), but has no data of value. To do this I am copying /boot and
mfsroot.gz from an mfsbsd iso image to boot to an MFS live system so I can wipe the drive
and do a clean install of 8.3. After booting to the MFS I do this:
dd if=/dev/zero of=/dev/ad2 bs=1m count=1
gpart create -s mbr ad2
gpart add -b63 -t freebsd ad2
gpart create -s bsd ad2s1
gpart add -i1 -s 1g -t freebsd-ufs ad2s1
gpart add -i2 -s 1g -t freebsd-swap ad2s1
gpart add -i4 -s 2g -t freebsd-ufs ad2s1
gpart add -i5 -s 1g -t freebsd-ufs ad2s1
gpart add -i6 -t freebsd-ufs ad2s1
gpart set -a active -i 1 ad2
gpart bootcode -b /boot/mbr ad2
newfs -U /dev/ad2s1d
newfs -U /dev/ad2s1e
newfs -U /dev/ad2s1f
followed by a sysinstall and some configuration. When I reboot I get a message that says
"Operating system not found" and the system hangs.
If I follow the same procedure but create a gpt partition it works swimmingly. I am OK
with using a gpt partition if needed, but for the sake of curiosity I would like to know
why I can't make the MBR partition partition work. Am I missing something?
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