[xenpreview-dev] vm-install: tap:aio instead of file

[Charles Coffing]

On Fri, Jul 27, 2007 at  9:46 AM, Gerd Bavendiek <gerd.bavendiek at gmx.net> wrote: 
> Hi,
> 
> according to the docs file backed virtual block devices should be 
> avoided, if heavy IO may occur. Use never sparse files here - so I read 
> on xen-users and: tap:aio should be preferred in such cases.
> 
> My question: Can this be done with vm-install ?

Not in SLES 10 SP1 or older.  Due to bugs in xend, this was not reliable, so I didn't put support in vm-install.

I am currently trying to make this work in openSUSE 10.3.  vm-install has support for this in 10.3, but xend still has some problems.


> If yes, how ?
> 
> If no, how can it be done manually (I tried, replacing file with tap:aoi 
> in a working configuration - boot froze) ?

On the latest openSUSE 10.3 alpha, you can specify the source of your disks using the same prefixes that Xen uses (so, "tap:aio:/var/lib/xen/images/vmname/disk0", or even "tap:qcow:/var/lib/xen/images/vmname/disk0").

Note that xend still has trouble booting from such a disk.  This should be fixed by beta 1.