Hi All, Sorry if this is a stupid question. I am walking into someone else''s xen install, and don''t have access to the host os at the moment. How do I tell just from a domU (with Ubuntu) if it is PV or HVM. I have looked through the forums and documentation and it seems to be very easy to figure this out from dom0, but unfortunately that isn''t possible at the moment. Thanks brun -- View this message in context: http://www.nabble.com/HVM-or-PV-tp24951818p24951818.html Sent from the Xen - User mailing list archive at Nabble.com. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hi Brun, Well, I have a suggestion that could works out if you are running your image in a Intel or AMD processor.Try looking at /proc/cpuinfo. If you don''t find a flag like these: For Intel: vmx For AMD: svm I''m almost pretty sure you have a PV Xen. I hope it was useful. []s Ronaldo. On Thu, Aug 13, 2009 at 6:29 AM, brun<jace21066@yahoo.com> wrote:> > Hi All, > > Sorry if this is a stupid question. I am walking into someone else''s xen > install, and don''t have access to the host os at the moment. How do I tell > just from a domU (with Ubuntu) if it is PV or HVM. > > I have looked through the forums and documentation and it seems to be very > easy to figure this out from dom0, but unfortunately that isn''t possible at > the moment. > > Thanks > brun > -- > View this message in context: http://www.nabble.com/HVM-or-PV-tp24951818p24951818.html > Sent from the Xen - User mailing list archive at Nabble.com. > > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Ronaldo Zacarias Afonso wrote:> > Well, I have a suggestion that could works out if you are running your > image in a Intel or AMD processor.Try looking at /proc/cpuinfo. > If you don''t find a flag like these: > > For Intel: vmx > For AMD: svm > > I''m almost pretty sure you have a PV Xen. > >Well, there is no flag. So is this definitely not hvm, or just unlikely hvm? -- View this message in context: http://www.nabble.com/HVM-or-PV-tp24951818p24954107.html Sent from the Xen - User mailing list archive at Nabble.com. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Thursday 13 August 2009, brun wrote:> Ronaldo Zacarias Afonso wrote: > > Well, I have a suggestion that could works out if you are running your > > image in a Intel or AMD processor.Try looking at /proc/cpuinfo. > > If you don''t find a flag like these: > > > > For Intel: vmx > > For AMD: svm > > > > I''m almost pretty sure you have a PV Xen. > > Well, there is no flag. So is this definitely not hvm, or just unlikely > hvm?I''m just an average xen user, but I''m not really sure this is a valid or reliable test. I have got a Dual CPU, dual core AMD Opteron 221 machine running xen. So I would expect the svm flag in /proc/cpuinfo. I don''t see it, neither in dom0, nor in any of my PV domUs. Regards, Geert -- Kobalt W.I.T. Web & Information Technology Brusselsesteenweg 152 1850 Grimbergen Tel : +32 479 339 655 Email: info@kobaltwit.be _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Geert Janssens wrote:> On Thursday 13 August 2009, brun wrote: >> Ronaldo Zacarias Afonso wrote: >>> Well, I have a suggestion that could works out if you are running your >>> image in a Intel or AMD processor.Try looking at /proc/cpuinfo. >>> If you don''t find a flag like these: >>> >>> For Intel: vmx >>> For AMD: svm >>> >>> I''m almost pretty sure you have a PV Xen. >> Well, there is no flag. So is this definitely not hvm, or just unlikely >> hvm? > > I''m just an average xen user, but I''m not really sure this is a valid or > reliable test. I have got a Dual CPU, dual core AMD Opteron 221 machine > running xen. So I would expect the svm flag in /proc/cpuinfo. I don''t see it, > neither in dom0, nor in any of my PV domUs.This test makes no sense at all, you wont see the vmx/svm flag in either the dom0 or any (PV|HVM) domU. Most often ''uname -a'' already helps, if its a distribution kernel (such as Centos) it will contain -xen if it''s PV. You can also check loaded modules, xenblk and xennet are a good indicator or the type of consoles available (hvc/xvc would suggest PV). Finally you could use lspci to look for qemu emulated devices (such as the RTL8139 nic) as an indicator for HVM (in PV lspci should return nothing unless you are passing through a "real" PCI device). Best regards, Christian _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Bugzilla from info@kobaltwit.be wrote:> > I''m just an average xen user, but I''m not really sure this is a valid or > reliable test. I have got a Dual CPU, dual core AMD Opteron 221 machine > running xen. So I would expect the svm flag in /proc/cpuinfo. I don''t see > it, > neither in dom0, nor in any of my PV domUs. >Thanks. This seems like a reasonable expectation. My understanding would be that svm is needed to support hvm, what I can''t seem to determine is whether or not it is imperative or simply makes certain functionality or something possible. -- View this message in context: http://www.nabble.com/HVM-or-PV-tp24951818p24954785.html Sent from the Xen - User mailing list archive at Nabble.com. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Thu, Aug 13, 2009 at 7:23 AM, brun <jace21066@yahoo.com> wrote:> Bugzilla from info@kobaltwit.be wrote: > > > > I''m just an average xen user, but I''m not really sure this is a valid or > > reliable test. I have got a Dual CPU, dual core AMD Opteron 221 machine > > running xen. So I would expect the svm flag in /proc/cpuinfo. I don''t see > > it, > > neither in dom0, nor in any of my PV domUs. > > Thanks. This seems like a reasonable expectation. My understanding would > be that svm is needed to support hvm, what I can''t seem to determine is > whether or not it is imperative or simply makes certain functionality or > something possible. >Very few, if any, of the second generation Opterons (xxx model numbers) support hardware virtualisation. IOW, you cannot run HVM on these CPUs. Without hardware virtualisation support in the CPUs/chipset, you can only run PV domains. All third-generation and newer Opterons (xxxx model numbers) support hardware virtualisation. -- Freddie Cash fjwcash@gmail.com _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Thursday 13 August 2009, Freddie Cash wrote:> On Thu, Aug 13, 2009 at 7:23 AM, brun <jace21066@yahoo.com> wrote: > > Bugzilla from info@kobaltwit.be wrote: > > > I''m just an average xen user, but I''m not really sure this is a valid > > > or reliable test. I have got a Dual CPU, dual core AMD Opteron 221 > > > machine running xen. So I would expect the svm flag in /proc/cpuinfo. I > > > don''t see it, > > > neither in dom0, nor in any of my PV domUs. > > > > Thanks. This seems like a reasonable expectation. My understanding > > would be that svm is needed to support hvm, what I can''t seem to > > determine is whether or not it is imperative or simply makes certain > > functionality or something possible. > > Very few, if any, of the second generation Opterons (xxx model numbers) > support hardware virtualisation. IOW, you cannot run HVM on these CPUs. > > Without hardware virtualisation support in the CPUs/chipset, you can only > run PV domains. > > All third-generation and newer Opterons (xxxx model numbers) support > hardware virtualisation.I see there is a type on my original mail. My opterons have model number 2214, so third-generation or newer. And they are indeed hvm capable. I am running several windows domU''s. Regards, Geert -- Kobalt W.I.T. Web & Information Technology Brusselsesteenweg 152 1850 Grimbergen Tel : +32 479 339 655 Email: info@kobaltwit.be _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Geert,> I''m just an average xen user, but I''m not really sure this is a valid > or reliable test. I have got a Dual CPU, dual core AMD Opteron 221 > machine running xen. So I would expect the svm flag in > /proc/cpuinfo. I don''t see it, > neither in dom0, nor in any of my PV domUs.I just learned this one a few weeks ago myself. You won''t see svm in /proc/cpuinfo, even if it''s enabled. Xen is a small(ish) OS that runs both dom0 and domU. Dom0 has more privileges, but it''s still a guest. Xen hides svm from both dom0 and domU -- probably because it needs to reserve those functions for itself. In any case, /proc/cpuinfo in dom0 reports what is available to dom0, not to Xen. To see what Xen sees, use "xm info" from dom0. The line that starts "xen_caps" should have entries with "hvm" if your hardware supports virtualization. (Thanks to Doug Magee for that info.) Good luck, -Brian Martin _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Thu, Aug 13, 2009 at 4:29 PM, brun<jace21066@yahoo.com> wrote:> > Hi All, > > Sorry if this is a stupid question. I am walking into someone else''s xen > install, and don''t have access to the host os at the moment. How do I tell > just from a domU (with Ubuntu) if it is PV or HVM.Why would it matter if it''s not yours? Can you ask for it to be converted to PV its currently HVM?> > I have looked through the forums and documentation and it seems to be very > easy to figure this out from dom0, but unfortunately that isn''t possible at > the moment.See http://lxr.xensource.com/lxr/source/tools/misc/xen-detect.c -- Fajar _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Thank you Brian, This information is very enlightning for me. Geert On Thursday 13 August 2009, Brian P. Martin wrote:> Geert, > > > I''m just an average xen user, but I''m not really sure this is a valid > > or reliable test. I have got a Dual CPU, dual core AMD Opteron 221 > > machine running xen. So I would expect the svm flag in > > /proc/cpuinfo. I don''t see it, > > neither in dom0, nor in any of my PV domUs. > > I just learned this one a few weeks ago myself. You won''t see svm in > /proc/cpuinfo, even if it''s enabled. Xen is a small(ish) OS that runs both > dom0 and domU. Dom0 has more privileges, but it''s still a guest. Xen > hides svm from both dom0 and domU -- probably because it needs to reserve > those functions for itself. In any case, /proc/cpuinfo in dom0 reports > what is available to dom0, not to Xen. > > To see what Xen sees, use "xm info" from dom0. The line that starts > "xen_caps" should have entries with "hvm" if your hardware supports > virtualization. (Thanks to Doug Magee for that info.) > > Good luck, > > -Brian Martin > > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users-- Kobalt W.I.T. Web & Information Technology Brusselsesteenweg 152 1850 Grimbergen Tel : +32 479 339 655 Email: info@kobaltwit.be _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users