Is there a way to support the execution of a PXE installation on a newly created domU? Kev _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Tue, 2005-12-13 at 12:22 -0800, Kevin Fox wrote:> Is there a way to support the execution of a PXE installation on a newly > created domU?Do you mean to do an installation? I don''t think you need the pxe boot. You just need to boot the kernel and the ramdisk for the installer? Only thing is you will have to use a Xen kernel, and then you will have to go into the ramdisk and replace the modules with the modules for the Xen kernel. Next problem I can think of is when you go to partition the disk. I am not sure what would happen there. I wonder if you export a partition if the installer will format it? Then it''s going to have to install the Xen kernel into the VM at the finish of install. But it would be cool to have an installer that would install a VM. brian -- Brian Lavender <brian@xensource.com> _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
>From Brian.Lavender@xensource.com Wed Dec 14 19:46:17 2005 > > On Tue, 2005-12-13 at 12:22 -0800, Kevin Fox wrote: > > Is there a way to support the execution of a PXE installation on a newly > > created domU? > > Do you mean to do an installation? I don''t think you need the pxe boot. > You just need to boot the kernel and the ramdisk for the installer? Only > thing is you will have to use a Xen kernel, and then you will have to go > into the ramdisk and replace the modules with the modules for the Xen > kernel.The intention would be a direct, non-interactive, installation from a PXE server. No preinstalled image exists on the allocated drive. Or maybe I''m misunderstanding your suggestion ... I would assume that the hypervisor would need to proxy the PXE installation for the GuestOS domain? Are you suggesting that the image pulled down by the initial first stage of the PXE tftpboot be a modified Xen kernel?> Next problem I can think of is when you go to partition the disk. I am > not sure what would happen there. I wonder if you export a partition if > the installer will format it? > > Then it''s going to have to install the Xen kernel into the VM at the > finish of install. > > But it would be cool to have an installer that would install a VM.Indeed ... can I assume from the reply that this hasn''t been looked at by anyone as yet? Thanks Brian Kev _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
OpenSuSE''s YaST2 has some domU installation support already, but it does not use PXE. PXE makes lots of sense for hardware assisted full virtualization. I actually plan to work on this shortly, it''s a fun assignment that hopefully won''t be incredibly difficult. I believe people have succesfully used PXE from QEMU using things like the netboot project [I want a full PXE environment with UNDI]. Having virtual block devices modelled as partitions instead of whole disks, or at least decoupling domU kernels from domU root filesystems [especially /lib/modules] makes life interesting, especially for upgrading domU''s. It''s initially harder to deal with full disk virtual block devices for things like reading the domU kernel while loading a domU, but I think the initial cost would be worth it, given the complexities of interactions between domU kernels and kernel modules with the current setup. Hopefully I''m missing something here. Regards. Andrew D. Ball aball@us.ibm.com On Wed, 2005-12-14 at 19:46 -0800, Brian Lavender wrote:> On Tue, 2005-12-13 at 12:22 -0800, Kevin Fox wrote: > > Is there a way to support the execution of a PXE installation on a newly > > created domU? > > Do you mean to do an installation? I don''t think you need the pxe boot. > You just need to boot the kernel and the ramdisk for the installer? Only > thing is you will have to use a Xen kernel, and then you will have to go > into the ramdisk and replace the modules with the modules for the Xen > kernel. > > Next problem I can think of is when you go to partition the disk. I am > not sure what would happen there. I wonder if you export a partition if > the installer will format it? > > Then it''s going to have to install the Xen kernel into the VM at the > finish of install. > > But it would be cool to have an installer that would install a VM. > > brian_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
on Thu, Dec 15, 2005 at 08:06:28AM -0800, Kevin Fox (kev@foxhole.sfbay.sun.com) wrote:> >From Brian.Lavender@xensource.com Wed Dec 14 19:46:17 2005 > > > > On Tue, 2005-12-13 at 12:22 -0800, Kevin Fox wrote: > > > Is there a way to support the execution of a PXE installation on a newly > > > created domU? > > > > Do you mean to do an installation? I don''t think you need the pxe boot. > > You just need to boot the kernel and the ramdisk for the installer? Only > > thing is you will have to use a Xen kernel, and then you will have to go > > into the ramdisk and replace the modules with the modules for the Xen > > kernel. > > The intention would be a direct, non-interactive, installation from a PXE > server. No preinstalled image exists on the allocated drive. Or maybe > I''m misunderstanding your suggestion ...PXE makes sense where you''re booting from bare hardware with minimal control over the startup process. A Xen domU boot isn''t quite equivalent to a BIOS boot. Xen, so far as the boot process is concerned, is more of a bootloader (GRUB/LILO) equivalent. What PXE provides is a way to, via the network interface, tell the BIOS what to load. Since Xen is already providing this capability, PXE is not appropriate. What you are looking for is a way to automate an install under a DomU, initiated by Xen. This is where Brian''s ramdisk (or other initial image) suggestion makes sense. What you''d want to do is fire off an image (ramdisk, file-backed VBD, whatever) with an additional VBD (the install target) specified, and use automated install tools (KickStart, AutoYAST, FAI, etc.) to complete your installation. In practice, what we''re seeing is creation of a library of candidate DomU images which can be deployed simply by copying them to an appropriate location (local storage, networked storage), or using COW VBDs. Deploying DomUs by way of distro installers in general isn''t necessary. The one place I''m using PXE boots under VMs is when using qemu to generate such image files (there''s a convenience factor to this). There''s a very useful PXE floppy image available at: http://etherboot.anadex.de/ ... which can be used via: qemu -fda eb_on_hd.ima -hda target.img -boot a ... where eb_on_hd.ima is the PXE floppy image and target.img is a prepared null-filed sparse file of appropriate size: dd if=/dev/zero of=target.img bs=1M seek=6000 count=0 Note that this produces a partitioned image file unless you manually specify partitioning during install. Some distros default to LVM configurations which throw in a few added twists. Foregoing partitioning an manually creating a single ext3 filesystem on /dev/hda (_not_ /dev/hda1...) within the installer is probably your best course. More on qemu: http://fabrice.bellard.free.fr/qemu/ Cheers. -- Karsten M. Self <karsten@xensource.com> XenSource, Inc. 2300 Geng Road #250 +1 650.798.5900 x259 Palo Alto, CA 94303 +1 650.493.1579 fax _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users