Full-virt vm creation ?

[Sp4rKY]

Hi,

I would find a way to create a full-virt vm, aka having it's
own
kernel/bootloader etc, so that its kernel_path,initrd_path params are
empty.

Do you know if it's complicated to do or if it can be easily done
using
debootstrap os ? (with some
modifications) ?

Cheers,

Maxence

[Iustin Pop]

With debootstrap OS it's not very easy, at least not with the released version
(0.7); in Git there are some extra hooks for installing grub, etc., on it.

iustin

[Sp4rKY]

> With debootstrap OS it's not very easy, at least not with the released version
> (0.7); in Git there are some extra hooks for installing grub, etc., on it.

Ok, I can see them. Is this only a kernel + grub install , or is there
something
else to
do ?

How can we, in hooks maybe, change the vm attributes (to
have
kernel_path/initrd_path empty without having to set them explicitely
in
command
line ) ?

Is there any drawbacks of using full-ivrt
vm ?

Thanks !

Maxence

[Iustin Pop]

On Fri, Dec 18, 2009 at 02:40:13AM -0800, Sp4rKY wrote:
> > With debootstrap OS it's not very easy, at least not with the released version
> > (0.7); in Git there are some extra hooks for installing grub, etc., on it.
> Ok, I can see them. Is this only a kernel + grub install , or is there
> something
> else to
> do ?

I'm not entirely sure, but that's what I would expect, yes.

Feel free to experiment and report!

> How can we, in hooks maybe, change the vm attributes (to
> have
> kernel_path/initrd_path empty without having to set them explicitely
> in
> command
> line ) ?

Simplest is to change them in the cluster defaults; otherwise you could try to
use instance creation hooks (post-phase) to modify the attributes.

> Is there any drawbacks of using full-ivrt
> vm ?

You mean booting the kernel from within the instance as opposed to
booting the kernel from outside? I don't know of any (well, security vs.
flexibility aside).

iustin

[Sp4rKY]

> I'm not entirely sure, but that's what I would expect, yes.
>
> Feel free to experiment and report!

Sure, I'll do :)

> > How can we, in hooks maybe, change the vm attributes (to
> > have
> > kernel_path/initrd_path empty without having to set them explicitely
> > in
> > command
> > line ) ?
>
> Simplest is to change them in the cluster defaults; otherwise you could try to
> use instance creation hooks (post-phase) to modify the attributes.

But I already have 60+ vm, using paravirt for some of them, will the
default attributes are only used for new vm creation ?

Maxence

[Iustin Pop]

No, for all. Then, the hooks are the only way. Are you referring to Xen or KVM
here?

iustin

[Sp4rKY]

> No, for all. Then, the hooks are the only way. Are you referring to Xen or KVM
> here?

what's the right way to modify attributes in hook ? (using gnt-
instance modify, or is there something more integrated, like env
vars ?)

I'm referring to KVM here.

Maxence

[Iustin Pop]

On Fri, Dec 18, 2009 at 02:51:35AM -0800, Sp4rKY wrote:
>
>
> > No, for all. Then, the hooks are the only way. Are you referring to Xen or KVM
> > here?
> what's the right way to modify attributes in hook ? (using gnt-
> instance modify, or is there something more integrated, like env
> vars ?)

Only gnt-instance modify.

> I'm referring to KVM here.

Ok, then yes, you need hooks.

iustin