Subject: Re: [vserver] Running Linux vServer and KVM on same Server
From: Herbert Poetzl <herbert@13thfloor.at>
Date: Thu, 29 Aug 2013 17:19:32 +0200

On Thu, Aug 29, 2013 at 10:24:09AM +0200, Urban Loesch wrote:
> Hi,

> we are using linux-vserver on debian since 2007 and we are 
> very happy with it. For our business it works very great.

Glad to hear that!

> But we have some requirements to run a few fully virtualized
> guests like redhat or centos where we need some specific
> kernels to run in the guest. 
> This special guests don't need many recources so we are
> thinking to run it on the some server together with some 
> of our linux-vserver guests.

> Have anyone of you experience with a setup like this?

Obviously it isn't well known, but I've been using qemu,
and later kvm for testing the Linux-VServer kernels since
ages and naturally, those testing happens on a host also
running a Linux-VServer kernel :)

> Are there any problems expectet to run linux-vserver and kvm
> together? Or are there some other better full virtualization
> technologies which we don't know?

So yes, it works exceptionally well and it really simple
to handle and control (both, Linux-VServer and kvm).
I haven't had any problems or issues with the setup for
a long time and there is nothing special you have to 
consider.

> For kvm we can use a dedicated nic to route all the traffic
> separated from the linux-vserver traffic.

No need for that, usually a tun interface on a bridge
will give you full flexibility, but of course, you can
also use a dedicated nic or whatever else you prefer.

HTC,
Herbert

> We intend to use kernel 3.10.x. It was announced as the next
> long term kernel:
> http://www.kroah.com/log/blog/2013/08/04/longterm-kernel-3-dot-10/

> Many thanks and regards
> Urban Loesch