thank you for replying

> boot wd0a:netbsd

yes of course i'm sorry, that's what i do and it doesn't match, ans yes 
'mount /dev/wd0a /mnt' matchs since the boot disks are totaly loaded.

So my question still there:
i probably need a special boot-floppy/kernel to mount the installed system.

Does such a floppy allready exist ?
If not, how can to make one ?

Thanks for your support