Great - thanks for the info! -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jan Mark Holzer Sent: Wednesday, October 03, 2007 7:40 PM To: Red Hat Enterprise Linux 5 (Tikanga) discussion mailing-list Subject: Re: [rhelv5-list] Xen - determining paravirtual vs. fully virtual?
Collins, Kevin [MindWorks] wrote: > > Hi, > > can anyone tell me how to determine (in Xen) whether a guest > OS was installed as paravirtual vs. fully virtual? Is that something > that can be changed without a re-install assuming the OS, RHEL5 in > this case, supports it? I've looked in the config files for the > various systems and I can't tell... > > Thanks, > > Keivn > > ------------------------------------------------------------------------ > > _______________________________________________ > rhelv5-list mailing list > [email protected] > https://www.redhat.com/mailman/listinfo/rhelv5-list > Hi, one of the easier options to figure out if you are running in a para-virt vs fully-virt/HVM guest is to use either check the kernel name and/or the output "dmidecode" (there are other examples as well but lets keep it easy first :) ) . At least in RHEL/Fedora the kernel used in dom0 and a para-virt guest has always the extension 'xen' (ie RHEL5 GA is 2.6.18-8.el5xen) , the kernel in a fully-virt/HVM guest will have the same name as the bare metal kernel (ie 2.6.18-8.el5 for RHEL5 GA if it is running as a fully-virt guest). In a HVM/fully-virt guest you could also use dmidecode and check the Vendor/Product fields which should come up as "Xen" (Vendor) and "HVM domU" (Product) . You can find a simple script at http://et.redhat.com/~jmh/virt-tools/scripts/ called xen-type.sh which can be used to figure out in which type guest and/or bare metal you are running . If you want to conver a fully-virt guest into a para-virt guest you'd have to install the para-virt kernel for the OS , make sure the entry for the para-virt kernel is the default boot target in your guest's /etc/grub.conf and edit /etc/modprobe.conf to add the following lines to it alias eth0 xennet alias scsi_hostadapter xenblk you also want to remove the lines referencing to eth0 and the physical ethernet card and the scsi_hostadapter if present and change it to point to xenblk The next step would be to edit the guest config file on your dom0/HyperVisor of the HVM guest and change the entries for vif, disk and remove the entry "type=ioemu" from them. You also may want to change the 'disk' entry and change file:/PathToYourGuestImage to tap:aio:/PathToYourGuestImage and the device name from hda (hvm) to xvda (pv) Next you want to uncomment/remove the entries for "builder" , "kernel" and "device_model" Now add a line for "bootloader="/usr/bin/pygrub" This should be it and you should be able to boot your guest again . Now you can configure the network inside the guest and you should be ready to go . I am not sure if it's documented in my notes on RHEL5/Virt at http://et.redhat.com/~jmh/docs/Installing_RHEL5_Virt.pdf but I will add a section to the document if it's not already included . Hth, Jan _______________________________________________ rhelv5-list mailing list [email protected] https://www.redhat.com/mailman/listinfo/rhelv5-list _______________________________________________ rhelv5-list mailing list [email protected] https://www.redhat.com/mailman/listinfo/rhelv5-list
