Re: Xen boot failures with disks >16K (tap device issues)

[David Hopper <dhop%nwlink.com@localhost>]

On Mar 20, 2011, at 8:00 AM, Manuel Bouyer wrote:

> On Sun, Mar 20, 2011 at 07:51:16AM -0700, David Hopper wrote:
>>> [...]
>>> Are you using a HVM domU, or a PV one ?
>>> The disk definition looks like a PV one, but you're also talking about
>>> tap(4) which is used only by HVM guests.
>> 
>> Well, I thought there were two kinds of "tap" devices when working with Xen, 
>> at least on NetBSD-- the Xen tap device which is used to define block access 
>> methods in a "disk" definition ("tap:aio", "tap:qcow"),
> 
> This is a linux thing, it's not used for NetBSD.

Got it.  Thanks!  *scowls at the Xen documentation*

>> What is the method for creating empty disk images for NetBSD/xen, if 
>> qemu-img isn't supported?  Just straight-up dd?
> 
> Yes, this is how I do it:
> dd if=/dev/zero of=disk.img bs=1m count=<size in mb>

So, the supported disk file access method is file: (or vnd, I imagine), and 
avoid qemu-img altogether when working with NetBSD/xen. I thought there might 
have been some magic in there for the disk format, but that's even better.

> -- 
> Manuel Bouyer <bouyer%antioche.eu.org@localhost>
>     NetBSD: 26 ans d'experience feront toujours la difference
> --

Thanks,
David