nanobsd image boot issues

[M. Warner Losh]

In message: <5aaae08a0904231438v5b655056g8852dc11f1e83987 at mail.gmail.com>
            Rick van der Zwet <info at rickvanderzwet.nl> writes:
: Boot delay and fail issues on various hardware using nanobsd generated
: RELENG_7_1 images on a sandisk 2gb CF (SDCFH2-002G). For example while
: trying to run a image on a soekris net4521 (bios 1.33) it seems to
: take ages (up to a minute) to start booting. Same image supplied to a
: PC (intel Pentium 1 & award bios) using a CF->IDE converter does not
: seems to boot at all, neither does a net4801 (bios 1.33). Just seems
: trying to find a boot loader. The net4801 even bails out after a
: while. Output of fdisk of image list as follows:
: 
:     Disk: /dev/disk3	geometry: 992/64/63 [4001760 sectors]
:     Signature: 0xAA55
:              Starting       Ending
:      #: id  cyl  hd sec -  cyl  hd sec [     start -       size]
:     ------------------------------------------------------------------------
:     *1: A5    0   1   1 -  491  15  63 [        63 -     495873] FreeBSD
:      2: A5  492   1   1 -  983  15  63 [    495999 -     495873] FreeBSD
:      3: A5  984   0   1 -  992  15  63 [    991872 -       9072] FreeBSD
:      4: 00    0   0   0 -    0   0   0 [         0 -          0] unused
: 

This looks right...

:  A reference pfSense image put on the same CF card is boot perfectly
: fine under the net4521 & PC (untested net4801):
: 
:     Disk: /dev/rdisk3	geometry: 992/64/63 [4001760 sectors]
:     Signature: 0xAA55
:              Starting       Ending
:      #: id  cyl  hd sec -  cyl  hd sec [     start -       size]
:     ------------------------------------------------------------------------
:      1: 00    0   0   0 -    0   0   0 [         0 -          0] unused
:      2: 00    0   0   0 -    0   0   0 [         0 -          0] unused
:      3: 00    0   0   0 -    0   0   0 [         0 -          0] unused
:     *4: A5    0   0   1 - 1023 254  63 [         0 -      50000] FreeBSD

This looks like the 'faked' DD geometry.

: Which makes me wonder about the sector start, why does nanobsd not
: start at sector 0, but uses sector 63 as a start instead. Could that
: be the explanation or is something else going on?

Because the first cylinder is reserved for the boot blocks.

Have you enabled packet mode for boot in boot0 with boot0cfg?

Warner