joe@js.ne.mediaone.net wrote:

> > I made it as "mknod md0c b 17 128" and then I can do mdconfig.
> > mdconfig(8) man page should also be fixed...
> > (It should be "mdconfig /dev/md0c 2048 &", not md0a.)
> 
> This allowed me to do an mdconfig having a /dev/mdcfg as block 17/128
> but i can't do a disklabel on it, etc. Where is this documented? Or is
> there an error with the user space mdconfig and md driver stuff? I
> couldn't do a newfs on the md drive due to bad partition info. 

Because the md device does not have its geometry info
and does not support the DIOCGDINFO ioctl. You have to make
disktab entries to use it as an filesystem.
The following commands works on my i386:

------
# ls -l /dev/md0* /dev/rmd0*
brw-r-----  1 root  operator  17,   0 Apr 13 18:07 /dev/md0
brw-r-----  1 root  operator  17, 128 Apr 12 19:44 /dev/md0c
crw-r-----  1 root  operator  24,   0 Apr 13 18:09 /dev/rmd0
crw-r-----  1 root  operator  24, 128 Apr 13 18:09 /dev/rmd0c
# mdconfig /dev/md0c 2880 &
[1] 9136
# newfs -T floppy /dev/rmd0
/dev/rmd0:      2880 sectors in 80 cylinders of 2 tracks, 18 sectors
        1.4MB in 5 cyl groups (16 c/g, 0.28MB/g, 128 i/g)
super-block backups (for fsck -b #) at:
 32, 632, 1184, 1784, 2336,
# mount /dev/md0 /mnt
# df /mnt
Filesystem  1K-blocks     Used    Avail Capacity  Mounted on
/dev/md0         1283        0     1218     0%    /mnt
#
------

> The md device that was configured could be dd'd from though, so it
> existed. I am still poking around, but if it works on one port, why
> doesn't it work on the others?

MAKEDEV scripts of some ports make wrong device node for the md.
It seems that few people use the md device except for md-root kernel,
then there are few documents...
---
Izumi Tsutsui
tsutsui@ceres.dti.ne.jp