Xen - Re State of accessibility on BSD systems

[Tony Baechler]

Hi,

Sorry to overquote here, but I'm confused by your message.  I do 
understand what virtualization is, but I wasn't 100% sure that Xen is in 
fact a virtualization product.  It looked like it requires special 
kernels with Xen patches, but the manual says it runs Windows XP.  I 
know what loop files are, but what is LVM or LVM2?  I know it stands for 
logical volume management, but how does that have to do with this?  
Other than knowing what LVM stands for, I have no clue what it does or 
why one would want it.  I noticed the Lenny installer offered it when I 
was setting up partitions but again with no explanation.  I would think 
that a CD image would be a .iso file which in turn would be a loop 
filesystem, so again how does LVM enter into it?  I did read a bit of 
the manual and it said nothing about any of this.  It said that one must 
use grub as a boot loader.  Does that mean that lilo won't work or are 
they suggesting grub because it's more flexible?  A step by step guide 
of exactly what to do to set up a basic VM would be helpful.  I see that 
there are special xen kernel images and modules, but I'm not sure how I 
would set up a primary and secondary linux VM setup.  For example, I 
would want to run a virtual Linux server inside a host server.  How?  
Once I get that working, I would like to play with NetBSD again since 
the manual says it has a Xen installer.  This still doesn't address how 
accessible all of this is.  With VMWare for example, I have no speech 
once I start even a text OS like FreeDOS unless I load a screen reader.  
Would this still apply in Xen?  If so, would that mean I would need 
sighted help?  The point for me would be to do this on my own, at least 
with BSD.  Sorry for so many questions, but Xen seems different than 
other VM solutions I've seen and I think I'm not grasping important 
things here.

luke wrote:
> Tony Baechler apparently wrote:
>
>   
>> Does anyone know about xen?  It can apparently run both BSD and Linux
>> and has console tools for administration,
>>     
>
> Both are true.  I use it heavily for running multiple Linuxes inside 
> Linux.  Beautiful system, Xen.
>
>   
>> Will it support multiple VMs such as a Linux host with BSD guest
>>     
>
> Such is the theory behind virtualization.:)  Yes.
>
>   
>> How would one install BSD on a xen VM?
>>     
>
> One method which _might_ work, is to setup a guest image which simply 
> contains the installation CD.  Boot it with what you need to get it into 
> text mode, and start a xen console on it, and you just might be able to 
> use the installer to install on to a virtually exported hard drive 
> partition, which you could later boot as its own guest.
>
> I think that some such scheme is described in the Xen user's Manual, 
> although it's been a couple years since I read that thing.
>
> A tip for using Xen and Linux virtualization in general: LVM2 is a near 
> must, if you're doing anything speculative.  Yes, you can use loop file 
> systems, and probably want to for the installer that we're talking about 
> here, but they are said to be slow for routine use, and I have no reason 
> to doubt that.
>