Re: Getting started with Xen -- Xen enabled kernel for Lenny?
My response at very bottom.
Rick Thomas wrote:
I'm trying to get started with Xen.
I've installed Lenny and a bunch of packages that looked interesting
and mentioned Xen in their descriptions. But there does not seem to
be a Xen enabled kernel available. Is Xen built-in to the Lenny
kernels, or what?
I plan to spend tonite with my feet up in the easy chair reading the
documents in /usr/share/doc/Xen-docs-3.1/ . I hope they will be
helpful, but they don't seem to mention Debian specifically. I've
googled every which way, but everything I find is for Etch or Sarge
and expects me to have a Xen enabled kernel.
More generally, is there a HOWTO or FAQ that would give me some
pointers to getting Xen up and running?
Sorry for any typos. There is a problem for newer Debian kernels (as in
the etch distribution) and Xen. They just don't work and there is
currently no patch to save the day. Ubuntu has Xen based recent kernels
which apparently work well but I have not yet tried them. The Xen web
site has 3 Xen options one of which I think is still free. Either one of
these 3 options can be installed providing a DOM 0 basic virtualizing
machine. Also, some of the other Linux distributions like SuSE have Xen
based kernels. Xen based kernels are regular kernels but have the Xen
application compiled into them making them the basis for hardware
virtualization and thus called DOM 0 meaning the virtualization machine
that redirects system calls from DOM U distributions. A DOM U
distribution is virtualized meaning that during the time slice for a
particular DOM U distribution it's system calls get re-routed to the DOM
0 computer resources (mostly hardware including CPU, memory, drives, LAN
interface, etc.). DOM U distributions each have their own partition and
are activated by the DOM 0 Xen application as a virtual machine..
There can be as many as 64 partitions in total including the partition
for DOM 0. Most designers prefer to have the DOM 0 Xen system as a
minimal distribution. The DOM 0 distribution can create virtual
machines from it's own distribution so that you might have several
virtual machines each doing one important thing instead of the
conventional way where all these things get done on the one
distribution. Of course, you can run other Linux distributions as DOM U
installations. This is what makes Xen most efficient.
Your fastest, safest, and best solution right now would be to get one of
the 3 optional systems offered by the Xen developers. Apparently, they
have a blog and I know they have a list. I have a download of the
free Xen package on a CD which is now a year old and which I will be
installing on a computer. I will install a large Debian distribution
as well as smaller Debian distributions each in their own partition and
use them as virtual machines. DOM 0 will be the free Xen package which
took me a week to download and now I am trying to find it. The Xen
documentation describes how the DOM 0 machine is made aware of the DOM U
partitions with their respective distributions. BTW, you can now take a
Windowzzzzz distribution like XP or more recent and run it as a DOM U
virtual machine.That's neat if you have applications like I have that
can only run on Windowzzzzz. But you have to buy a license from MS.
Hope this information gets you going. There is one fellow on the
debian-user list that has had a Linux Xen system running for about 2
years or more but that system would be running on an older kernel and he
would have compiled the Xen application into the kernel and I think he
used the AMD CPU. A number of people have tried to update their older
Debian kernel with patches which automatically makes their system non
operational. I think Debian really missed the importance of Xen and to
get a Debian DOM 0 system from the etch distribution was not possible.
Apparently there is a new distribution by what I hear on the list
chatter. That distribution I am not aware of other than it is Debian 4.x
distribution. Hopefully, if that is the case there may now be kernels
available with the Xen application installed.
Have a nice day and if you get Xen up and running please be kind enough
to let the list know about your configuration and other issues as there
have been many over the last few years that have wanted help and advice.
I reiterate, your best chance of success is to run out of the Xen box as
provided by the Xen developers.
Thanks -- Ted