[CentOS] Xen Install manager won't let me install anything.

Fri May 6 06:24:44 UTC 2011
Pasi Kärkkäinen <pasik at iki.fi>

On Thu, May 05, 2011 at 04:53:22PM -0400, Martes G Wigglesworth wrote:
> 
> On 05/05/2011 09:09 AM, Pasi Kärkkäinen wrote:
> > It sounds like your hardware does not have HVM support,
> > which means you can only run PV VMs.
> Thanks for the reply.
> 
> You are correct.
> 
> I have two P4 32-bit machines that I just picked up and wanted to use 
> them for testing until I can afford to upgrade to the 12-core 
> MB/Processors that I bought these 2u chassis into which I plan to install.
> 
> I have never used xen, and it just seems kind of odd that you cannot 
> simply install from the hard drive, like on virtualbox.  Anyhow, I could 
> only figure that was the outlying factor.
> 
> I could not locate that aspect of the virt-manager docs, so I will check 
> again.
> 

Not being able to install from ISO image as PV VM is a virt-manager limitation.
(and partly centos/rhel distro limitation).


> Anyhow, now I am fighting with SL-Linux's installation media for i386, 
> having the ability to be seen, and booted, but inside their own boot 
> menue, it forces you to re-verify that you have install media. (Even 
> though it is running from the media in the first place.  Then Xen 
> magically can't see the iso that SL linux is running from.)
> 
> Are there any good (I guess dated, now that everything is mulit-core) 
> docs on how to work with paravirtualization, since I have to deal with 
> this weird "network" install setup?  It seems that I can put in the 
> explicit path to the local-disk-installed ISO image, but the second it 
> boots, nothing can be found, and it asks me to put in a url, etc...
> 

RHEL/CentOS docs have examples...
http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Virtualization/index.html

cmdline virt-install example to install PV RHEL5/CentOS5:
http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Virtualization/chap-Virtualization-Guest_operating_system_installation_procedures.html#sect-Virtualization-Installing_Red_Hat_Enterprise_Linux_5_as_a_para_virtualized_guest

Fedora can be installed as Xen PV VM in the same way..
just give fedora mirror URL instead of RHEL/CentOS mirror URL.


> 
> I know this sounds incoherent, but I am burnt out from exams.
> > Installation for PV (paravirtualized) VMs is only supported
> > by using netinstall in virt-manager.
> >
> > HVM (fully virtualized) VMs can be installed from ISO image.
> Thanks for the input, and would appreciate any further direction on 
> reading further on "real-world" installs, not the docs where they assume 
> you have a quad 12-core processor super server so "everything thing just 
> works in virtualmode... )  I guess this is more for virt-manager, but I 
> think you will understand what I mean if you check the doc site for virt 
> manager.  They don't even mention that there is a limitation such as 
> what you have described, except to say "there is a limitation."
> 
> Sorry for the ramble. Need more RedBull, or maybe not so much???? Lol..
> 

Hehe.

You can also use other tools than virt-manager/virt-install to install VMs.

- debootstrap to install Debian/Ubuntu VMs.
- thirdparty "xen-tools" to install Debian/Ubuntu VMs.
- febootstrap to install fedora.
- various chroot tricks to install rpm-based distros.
- Fedora native installer, by downloading the fedora installer pxeboot
  kernel + initrd and booting them as xen pv domU.
- Debian/Ubuntu native installer, by downloading the debian 6.0 or ubuntu 10.04
  installer netinstall kernel + initrd and booting them as xen pv domU.


See the end of the tutorial for an example how to install ubuntu manually using the distro installer:
http://wiki.xen.org/xenwiki/Fedora13Xen4Tutorial

-- Pasi