May 2008 - openSUSE Virtual - openSUSE Mailing Lists

Re: [opensuse-virtual] Problems with Xen-installation resp. configuration
by gildo.rex＠gmx.de 19 May '08

19 May '08

Hi Andrew, > > Do I get this right, that I cannot install a paravirtualized guest from > the CD, but I can install a Xen-Server from the CD? > > > That may be the case (I'm not certain of the detailed > technicalities), but I do know that although I have performed 1-CD > installs and then installed the xen kernel, any installations of > virtual machines needed to be performed using the DVD media. The good > news is that it doesn't need to be burnt to disk first! It's fine to > just point the installer to the DVD ISO image saved somewhere on the > local filesystem. Your hint made my saturday!!! The installation worked and the VMs are performing well (better than VMware). Many thanks! I have got one more challenge to master: As I'm doing clustertest I'm installing the VMs on one host and test them on this host. The next step is to spread the VMs across to hosts. So I need to migrate on of the DomUs. With VMware I simply copied the VM to the other physical node and started it. I tried the same with the DomU and copied the configfile as well as the Diskfile. When I try to start the DomU on the other node, I get the error message: mpiphysicaltest2:~ # /usr/sbin/xm create /etc/xen/vm/test2 -c Using config file "/etc/xen/vm/test2". Error: (2, 'Invalid kernel', 'xc_dom_compat_check: guest type xen-3.0-x86_32 not supported by xen kernel, sorry\n') I checked the kernel via 'uname': stephan@mpiphysicaltest1:~> uname -a Linux mpiphysicaltest1 2.6.22.17-0.1-xen #1 SMP 2008/02/10 20:01:04 UTC i686 i686 i386 GNU/Linux stephan@mpiphysicaltest1:~> uname -r 2.6.22.17-0.1-xen stephan@mpiphysicaltest2:/usr/lib/xen/boot> uname -a Linux mpiphysicaltest2 2.6.22.17-0.1-xenpae #1 SMP 2008/02/10 20:01:04 UTC i686 i686 i386 GNU/Linux stephan@mpiphysicaltest2:/usr/lib/xen/boot> uname -r 2.6.22.17-0.1-xenpae On the second node (target node), the kernel seems to have a PAE-extension. Might that hinder the migration? I don't know where it derives from - I installed both kernel from the same CD from scratch... How can I harmonize this?? Kind Regards Stephan -- GMX startet ShortView.de. Hier findest Du Leute mit Deinen Interessen! Jetzt dabei sein: http://www.shortview.de/?mc=sv_ext_mf@gmx -- To unsubscribe, e-mail: opensuse-virtual+unsubscribe(a)opensuse.org For additional commands, e-mail: opensuse-virtual+help(a)opensuse.org

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Re: [opensuse-virtual] Problems with Xen-installation resp.configuration
by gildo.rex＠gmx.de 19 May '08

19 May '08

Hi Jason, thanks for your exact explanations. > > There are two different 32-bit xen kernels shipped with openSUSE 10.3: > kernel-xen and kernel-xenpae. (Note that there are different hypervisor > versions that match these kernel versions as well [xen.gz and xen-pae.gz]). > These kernels mirror the kernel-smp and kernel-bigsmp that are typical in SuSE > distributions, and they are installed automatically based on the amount of > memory in your system (basically <= 2GB installs the kernel-xen; > 2G > installs the kernel-xenpae). The kernel within the guest* has to match the > flavor of the kernel that is running on the host (i.e. if you are running > -xenpae, your guest must be running -xenpae). Yes, you're right. I've checked that meanwhile, and I didn't get two absolutely identical machines. One has 4 GB, the other 2 GB... (trust only in what you did yourself) > > NOTE: I am only speaking of paravirtualized guests in this case. The > kernel in a fully virtualized guest does not need to match the "flavor" of the > hypervisor/dom0 kernel with the exception that you have to be running a > 64-bit xen in order to run any 64-bit guest. Ok, thats clear. But I want to run it paravirtualized. > > > How can I harmonize this?? > > > > There are a couple of different approaches that you can take here. One > option is to make both hosts run the same flavor of xen. Since there are > only a handful of processors newer than the Pentium Pro that do not have PAE > support, my recommendation would be to install the kernel-xenpae package > into your host that is currently running the -xen kernel. This will > automatically create a new entry in your grub menu that will load the right > hypervisor as well. > > However, if you choose this route, you will want to install the > kernel-xenpae kernel into all of your guests BEFORE you move to the xenpae kernel on > the host. Otherwise, your VM won't boot on either system and you'll have > to use some tricks to install the correct kernel in the vm (read "Requires > you to be somewhat of a Linux expert"). You'll also need to change your > config file to point at the -xenpae kernel, but I'll explain that in a moment. > The other option seems to be easier to me, so I'll omit the first one. > This leads me to the second option which is to install BOTH kernels in > your VM. That way, by changing a single line in your vm config file, you'll > be able to boot the VM on either machine without changing the hypervisor > that is currently running. The line that you'll need to change is the one > that references /boot/kernel-xen and /boot/initrd-xen (I believe it is the > bootargs line, but without looking at your config file, I can't be sure). Here's the config file of the VM: name="test2" ostype="opensuse" uuid="e8fa2bfb-54c9-440a-43fa-a58b361ce80e" memory=512 vcpus=1 on_crash="destroy" on_poweroff="destroy" on_reboot="restart" localtime=0 builder="linux" bootloader="/usr/lib/xen/boot/domUloader.py" bootargs="--entry=xvda2:/boot/vmlinuz-xen,/boot/initrd-xen" extra=" " disk=[ 'file:/var/lib/xen/images/mpichxentest2/disk0,xvda,w', ] vif=[ 'mac=00:16:3e:00:00:02', ] vfb=['type=vnc,vncunused=1'] So I have to change the line bootargs="--entry=xvda2:/boot/vmlinuz-xen,/boot/initrd-xen" to bootargs="--entry=xvda2:/boot/vmlinuz-xen-pae,/boot/initrd-xen-pae" ? > Once you have installed the kernel-xenpae package into the guest, you can copy > it to the PAE host and change those entries to -xenpae. Stupid question: How do I install that kernel? Via Yast on the original system? If I may summarize: I install both kernels in the VM. Via the bootargs-line in the config file, I can refer to one of the kernels. On the PAE-host, it refers to the PAE-kernel, on the non-PAE-host, it refers the non-PAE-kernel. So I could have a local version of the config file on each host, and just copy the diskfile, when I change the installation. Did I get it?? > If you have > problems with this, attach your vm config file and any error messages, and I'll > take a look. > > Have a lot of fun! > > Jason > > P.S. If you are interested in actual VM migration (movement of the VM > while it is still running), you'll need to have both hosts running the same > flavor of xen, and you'll need the VM disk to be accessible to both machines > in the exact same way (i.e. iscsi target, nfs mount, or other). But for > now, this should be plenty to get you started. Good luck! No, at the moment I only need cold migration for my work. I'll possibly get back to that lateron. Kind regards Stephan -- Psssst! Schon vom neuen GMX MultiMessenger gehört? Der kann`s mit allen: http://www.gmx.net/de/go/multimessenger -- To unsubscribe, e-mail: opensuse-virtual+unsubscribe(a)opensuse.org For additional commands, e-mail: opensuse-virtual+help(a)opensuse.org

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Re: [opensuse-virtual] Problems with Xen-installation resp. configuration
by gildo.rex＠gmx.de 16 May '08

16 May '08

Hi Andrew, thanks for your answer! > I think that the problem you have encountered is that the single CD > of OpenSUSE 10.3 doesn't contain the paravirtualised kernel. Do I get this right, that I cannot install a paravirtualized guest from the CD, but I can install a Xen-Server from the CD? > > In my testing of Xen, I've got around this by using an ISO image of > the installation DVD, or (for a very convenient solution), I've set > up an installation server, which will allow you to use an HTTP > installation source for network installations. The instructions are > here: > http://en.opensuse.org/SDB:Installation_Server > (although I have used a SLES machine as installation server on my > network). > If you are using an installation source for Xen, you do not need to > use a mini installation CD (which would be needed to install on a > physical machine), you would just need to specify the network > installation source in the following format: > http://server_hostname_or_IP/install/10.3/CD1 > You would need to specify the appropriate hostname or IP address (of > course), and "install" is the directory alias that you specify during > the setup of the installation server. 10.3 is the source name of the > product, which you set up when loading the data from the ISO images - > don't forget the trailing /CD1 (it won't find the installation files > without it). > The only other thing to watch is that when creating an installation > source it will ask you to change CDs even if you have given it all > the files that it will need (perhaps from a DVD ISO image). When that > happens, just press cancel - the source will have been configured > successfully. > I hope that helps, Thanks for that detailed instruction, but as I am not am Linux-Expert and that installation is just the way to my actual aim, I'd like to keep it as simple as possible. If I got everything right, it would help, if I'd just use the DVD instead of the CD, right? Kind regards Stephan -- Der GMX SmartSurfer hilft bis zu 70% Ihrer Onlinekosten zu sparen! Ideal für Modem und ISDN: http://www.gmx.net/de/go/smartsurfer -- To unsubscribe, e-mail: opensuse-virtual+unsubscribe(a)opensuse.org For additional commands, e-mail: opensuse-virtual+help(a)opensuse.org

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[opensuse-virtual] Problems with Xen-installation resp. configuration
by gildo.rex＠gmx.de 16 May '08

16 May '08

Hi all, I want to perform a performance test and compare physical and virtual platforms. To ensure comparability I want to install openSuSE 10.3 in the physical machines as well as in the VMware-VMs, in the Xen-DomUs and so on... I've installed Xen as package right from scratch with a fresh installation of openSuSE 10.3 on my computer system. I can boot the system into the Xen-Kernel Now I'm running into problems with setting up DomUs: I'm using the "Create Virtual Machine"-program, for the setup, which is installed along with the Xen-package. It asks for the config of the new VM resp. DomU. At "Operating System Installation" I'm asked to provide an installation source. Therefor I wanted ot use a local iso-image on the desktop. I used the same for installing VMware-VMs. Unfortunately I get teh error message: "installation source is unusable". The same when using the physical CD via the physical CD-ROM-drive. If I choose Full Virtualization instead of Paravirtualization, I get no error message. A VNC-window opens, which indicates, that a process is being started, but the process seems to stuck when loading the iso-image. I have 3 programs available in YaST2 under "Virtualization": 1.) Create Virtual Machines -> doesn't work, like explained. 2.) Install Hypervisor and Tools -> States, that the hypervisor and the tools are properly installed. 3.) Virtual Machine Manager -> Doesn't start and gives the following error message on console: xend [ERROR] Config file does not exist: /etc/xen/xend-config.sxp But that file exists. I've changed the permission, but the Virtual Machine Manager doesn't start nevertheless. Besides I recognize, that the physical hasn't got a NW-link after the booting the xen-kernel. Under "Network Settings" I see, that the normal device isn't connected. When leaving the NW-setting, the link works (although I didn't edit anything). The Xen-daemon is running, as I checked via sudo /etc/init.d/xend start Can anybody tell me whats wrong with my installation?? May there any configuration be missing. Do you have some hints, how I can troubleshoot that issue? I'm almost desperate!!! Thanks in advance and kind regards Stephan -- Der GMX SmartSurfer hilft bis zu 70% Ihrer Onlinekosten zu sparen! Ideal für Modem und ISDN: http://www.gmx.net/de/go/smartsurfer -- To unsubscribe, e-mail: opensuse-virtual+unsubscribe(a)opensuse.org For additional commands, e-mail: opensuse-virtual+help(a)opensuse.org

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[opensuse-virtual] Xen DomU on LVM
by Wolfgang Rosenauer 07 May '08

07 May '08

Hi, This is on openSUSE 10.3: I'm trying to setup Xen guests on LVM logical volumes. What I want to achieve is: - better performance as with file based VBDs - easy resizing options for guest filesystems So my plan was to use LVs directly as partitions in the guest /dev/vg/lv1 -> /dev/hda1 /dev/vg/lv2 -> /dev/hda2 (or /dev/hdb1 FWIW) According to documentation I found, that should be possible but I wasn't able to get it to work. Probably the only issue is YaST anyway but I'm not sure and I actually want to be able to install within a DomU. Xen is always using the VBDs as whole disks so that /dev/hda1 ends up being a disk which needs a partition table and partition within DomU. While using one LV for the whole DomU disk would be possible it makes resizing much harder since DomU doesn't know about LVM so I can resize the "disk" but it's not really possible to resize the partitions within DomU. Any ideas? Wolfgang -- To unsubscribe, e-mail: opensuse-virtual+unsubscribe(a)opensuse.org For additional commands, e-mail: opensuse-virtual+help(a)opensuse.org

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