backup z/os dasd from z/linux

[Sergey Korzhevsky]

I've tried to backup z/os dasd (actually, get image of it) from linux but
with no success.

First, i attached it to linux:

  echo "add range=806(ro)" >> /proc/dasd/devices
  cat /proc/dasd/devices

072e(ECKD) at ( 94:112) is dasdac     : active at blocksize: 4096, 296400
blocks, 1157 MB
0806(ECKD) at ( 94:116) is dasdad (ro): ready


So, only "ready", no info about size.
In /var/log/messages:

dasd(eckd): /dev/dasdad ( 94:116),[EMAIL PROTECTED]: Trk 0: no records after VTOC!
dasd(eckd): /dev/dasdad ( 94:116),[EMAIL PROTECTED]: Volume has incompatible disk
layout


Then

 dd if=/dev/dasdad of=806.img bs=4096
0+0 records in
0+0 records out



So, is it possible?

        WBR, Sergey