current best practice for booting >2TiB volumes?

[eric%cirr.com@localhost (Eric Schnoebelen)]

What is the current best configuration practice for booting from
a device that is greater than 2TiB?

I'm currently trying to use gpt(8) and dk(4) wedges..

I've got a pair of Hitachi HDS723030ALA640 SATA drives, with
5860533168 sectors of 512 bytes.

I've created a wedge on each drive as the first GPT index. I've
pulled them together as a raid volume, and then created my root
filesystem on raid0a within.

I've used ``gpt biosboot -i 1 wd2'' to set the GPT boot
partition.

I've put /boot in raid0a, and used installboot to set the boot
loader (bootxx_ffsv1) on wd2 and wd3.

When I attempt to boot (after relocating wd2/3 to wd0/1), the gpt
mbr loads bootxx_ffsv1, but bootxx_ffsv1 complains it can't find
/boot in the root filesystem.

I'm pretty sure I've set everything in accordance with building
a RAID-1 root filesystem.

Interesting configuration bits:

egsner-> sudo gpt show wd2
       start        size  index  contents
           0           1         PMBR
           1           1         Pri GPT header
           2          32         Pri GPT table
          34           6         
          40    21037056      1  GPT part - NetBSD RAIDFrame component
    21037096  1499463680      3  GPT part - NetBSD RAIDFrame component
  1520500776   209715200      4  GPT part - NetBSD RAIDFrame component
  1730215976  4130317159         
  5860533135          32         Sec GPT table
  5860533167           1         Sec GPT header
egsner-> sudo gpt show  -l wd2
       start        size  index  contents
           0           1         PMBR
           1           1         Pri GPT header
           2          32         Pri GPT table
          34           6         
          40    21037056      1  GPT part - "atlantis-dom0.a"
    21037096  1499463680      3  GPT part - "egsner-vm.b"
  1520500776   209715200      4  GPT part - "bob-the-builder.b"
  1730215976  4130317159         
  5860533135          32         Sec GPT table
  5860533167           1         Sec GPT header
#
#       The interesting volume is atlantis-dom0.[ab]
#
egsner-> disklabel raid0
# /dev/rraid0d:
type: RAID
disk: raid
label: fictitious
flags:
bytes/sector: 512
sectors/track: 16
tracks/cylinder: 8
sectors/cylinder: 128
cylinders: 164351
total sectors: 21036992
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0           # microseconds
track-to-track seek: 0  # microseconds
drivedata: 0 

8 partitions:
#        size    offset     fstype [fsize bsize cpg/sgs]
 a:    262144        63     4.2BSD   1024  8192     0  # (Cyl.  0*-   2048*)
 b:   1048576    262207       swap                     # (Cyl.  2048*-  10240*)
 c:  21036992         0     unused      0     0        # (Cyl.  0 - 164351*)
 d:  21036992         0     unused      0     0        # (Cyl.  0 - 164351*)
 e:  16514944   1310783     4.2BSD   4096 16384     0  # (Cyl.  10240*- 139263*)
 f:   3211265  17825727     4.2BSD   4096 16384     0  # (Cyl.  139263*- 
164351*)


--
Eric Schnoebelen                eric%cirr.com@localhost          
http://www.cirr.com
    Out the 10Base-T, through the router, down the T1, over the leased line,
            off the bridge, past the firewall... nothing but Net.