Hi,

there seems to be some confusion here.

Marcin Jessa wrote:
> I dont want to copy hundreds of files to the CF. I want to have one image which I can dd to the CF.

What I usually do is use vnd(4) to create a complete image of the CF 
card, although makefs should do as well.

> What I am trying to do is to mount the rootfs on the CF (wd0) instead of md0.

Then you will have to "copy hundreds of files to the CF". Either with 
cp/tar or with vnd+newfs (or makefs+dd). What do you need the md0 image 
in the kernel for?

If you want to mount wd0a read-only and then mount some memory disks on 
top, that's not what MEMORY_* is for as far as I understand. man 
mount_mfs or man mdconfig.

Regards,

ND