Xen users - Mar 2007 - mounting using "xm block-attach" does not work; "special device /dev/xvda1 does not exist." error

Hello, 
I read the  blktap readme; there is a section there
titled:
Mounting images in Dom0 using the blktap driver.

It says there that you can mount an image by:
xm block-attach 0 tap:aio:<FILENAME> /dev/xvda1 w 0
mount /dev/xvda1 /mnt/disk        <--- don''t use loop
driver
This option also appears in:
http://wiki.rpath.com/wiki/Xen_DomU_Guide 

I assume that this option is not only for Xen
unstable, but also for Xen releases. (Am I right?)

I tried the following:

I have  xen 3.0.3 (from rpm packages) on Fedora Core 6
on i386.

I had created an domU image using the Virtual Machine
Manager, choosing the “simple file” option.
This image is : /xenGuest/fc6Guest.

I can start and use this domU successfully using this
image.

In this domU config file, the “disk=”  line says:

disk = [ ''tap:aio:/xenGuest/fc6Guest,xvda,w'', ] 

Now I tried to mount it from dom0 , when domU is not
running , thus:
xm block-attach 0 tap:aio: tap:aio:/xenGuest/fc6Guest
/dev/xvda1 w 0

This command was performed probably OK (it did not
emit any error messagge, and in fact it did not emit
any message at all).
and then:
mount /dev/xvda1 /mnt/disk        
But I get an error : 
Mount: special device /dev/xvda1 does not exist.
Also ls -al /dev/xvda* shows nothing.
But , just for testing, I ran **again** 
xm block-attach 0 tap:aio: tap:aio:/xenGuest/fc6Guest
/dev/xvda1 w 0
and then it said:
Error: device /dev/xvda1 (51713,tap) is already
connected.
Usge:..


So I do not understand. Any ideas ???
Am I missing something ? What is wrong here ? 

Regards,
Xu 







 
____________________________________________________________________________________
Be a PS3 game guru.
Get your game face on with the latest PS3 news and previews at Yahoo! Games.
http://videogames.yahoo.com/platform?platform=120121

_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users