Re: XEN help needed

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Mon, Nov 09, 2020 at 08:04:04AM -0800, Paul Goyette wrote:
> (Cross-posting at recommendation of a private response - please cc me
> on any reply, as I generally don't follow this list.)
> 
> 
> Hello all you XEN experts!
> 
> I've got a XEN3_DOMU virtual machine currently running NetBSD 8.1, and
> hosted on a commercial provider (www.prgmr.com).  Since I'm running
> 8.1 I think that implies that I'm running in HVM mode?

It could also be PV. A dmesg would tell you ...

> 
> Anyway, the provider will soon be upgrading their host to a PVHVM-only
> environment.  That means that I need to upgrade, to -current.
> 
> So, a few questions.  (I'm a really dummy when it comes to XEN, so
> please forgive me if the questions don't make sense!  Where's my copy
> of O'Reilly's ``XEN For Dummies'' when I need it?  :)  )
> 
> 1. Since I'm switching to PVHVM, will there be any differences in the
>    "visible" devices?  Will I need to update my kernel config?  Or
>    will a -current XEN3_DOMU kernel work "out of the box"?

for PVHVM, you don't want a XEN3_DOMU kernel, but GENERIC

The device name will change if actually run HVM, and will not if you actually
run PV.

> 
> 2. Will I be able to update only my kernel, and continue running my
>    8.1 userland?

Yes, as long as you have COMPAT_80 it should work. You may have some issues
with things like IPF ...

> 
> 3. Will I need to make any configuration changes to things in /etc ?

If device name changes, you'll have to update fstab and network configs.

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