lala4@root 17:43:52/160101(~)% gpt show raid1
       start        size  index  contents
           0  8664872832         
lala4@root 17:44:03/160101(~)% 

lala4@root 18:06:04/160101(~)% gpt show raid1  
       start        size  index  contents
           0           1         PMBR
           1           1         Pri GPT header
           2          32         Pri GPT table
          34  8664872765         
  8664872799          32         Sec GPT table
  8664872831           1         Sec GPT header
lala4@root 18:06:05/160101(~)% gpt add -s 8664872765 raid1
Partition 1 added, use:
        dkctl raid1 addwedge <wedgename> 34 8664872765 <type>
to create a wedge for it
lala4@root 18:06:34/160101(~)% dkctl raid1 addwedge dk1 34 8664872765 
usage: dkctl device
       dkctl device command [arg [...]]
   Available commands:
        getcache 
        setcache none | r | w | rw [save]
        synccache [force]
        keeplabel yes | no
        badsector flush | list | retry
        addwedge name startblk blkcnt ptype
        delwedge dk
        getwedgeinfo 
        listwedges 
        makewedges 
        strategy [name]
lala4@root 21:12:14/160101(~)% dkctl raid1 addwedge dk1 34 8664872765 ffs
dk0 created successfully.
lala4@root 21:12:37/160101(~)% gpt show raid1
       start        size  index  contents
           0           1         PMBR
           1           1         Pri GPT header
           2          32         Pri GPT table
          34  8664872765      1  GPT part - NetBSD FFSv1/FFSv2
  8664872799          32         Sec GPT table
  8664872831           1         Sec GPT header

lala4@root 21:13:17/160101(~)% newfs -O 2 /dev/dk1
newfs: /dev/rdk1: open for read: Operation not supported by device

lala4@root 21:14:52/160101(~)% dkctl raid1 listwedges
/dev/rraid1d: 1 wedge:
dk0: dk1, 8664872765 blocks at 34, type: ffs

lala4@root 21:14:56/160101(~)% newfs -O 2 /dev/dk0   
/dev/rdk0: 4230895.0MB (8664872760 sectors) block size 32768, fragment size 4096
        using 5700 cylinder groups of 742.28MB, 23753 blks, 46848 inodes.
super-block backups (for fsck_ffs -b #) at:
192, 1520384, 3040576, 4560768, 6080960, 7601152, 9121344,
  10641536, 12161728, 13681920, 15202112, 16722304, 18242496,
  19762688, 21282880, 22803072, 24323264, .............