What version of QEMU do you have installed ? Libvirt has recently become more aggressive at requiring modern QEMU versions, so its possible if your old libvirt was running against old QEMU, that might not be supported with new libvirt.

> > > > What version of QEMU do you have installed ? Libvirt has recently > > become more aggressive at requiring modern QEMU versions, so its > > possible if your old libvirt was running against old QEMU, that > > might not be supported with new libvirt. > > I'm using QEMU 2.8 here. > That might explain why libvirt cannot find a version that is modern enough. 2.8 is plenty new enough, so that's not the issue.

On Wed, Jun 13, 2018 at 05:59:37PM +0300, Mathieu Tarral wrote: > >> > > >> > What version of QEMU do you have installed ? Libvirt has recently > >> > become more aggressive at requiring modern QEMU versions, so its > >> > possible if your old libvirt was running against old QEMU, that > >> > might not be supported with new libvirt. > >> > >> I'm using QEMU 2.8 here. > >> That might explain why libvirt cannot find a version that is modern enough. > > > > 2.8 is plenty new enough, so that's not the issue. > > Alright, so let's focus on libvirt 4.4.0. > > When I start the daemon, i can see some warnings related to QEMU: > > warning : virQEMUCapsInit:942 : Failed to get host CPU cache info > warning : virQEMUCapsInit:949 : Failed to get host power management capabilities > > Could this be the reason, or the beginning of an explanation ? > How can I dig and find what is the root cause ? Best bet is to edit libvirtd.conf and set log_filters="1:qemu_capabilities" log_outputs="1:file:/var/log/libvirtd.log" and then rm -rf /var/cache/libvirt/qemu and restart libvirtd. The log file should tell you it is detecting qemu-system-x86_64 and probing it. If anything fails it should be covered in the logs.

On Wed, Jun 13, 2018 at 06:13:04PM +0300, Mathieu Tarral wrote: > 2018-06-13 18:07 GMT+03:00 Daniel P. Berrangé <berrange(a)redhat.com&gt;: > > On Wed, Jun 13, 2018 at 05:59:37PM +0300, Mathieu Tarral wrote: > >> >> > > >> >> > What version of QEMU do you have installed ? Libvirt has recently > >> >> > become more aggressive at requiring modern QEMU versions, so its > >> >> > possible if your old libvirt was running against old QEMU, that > >> >> > might not be supported with new libvirt. > >> >> > >> >> I'm using QEMU 2.8 here. > >> >> That might explain why libvirt cannot find a version that is modern enough. > >> > > >> > 2.8 is plenty new enough, so that's not the issue. > >> > >> Alright, so let's focus on libvirt 4.4.0. > >> > >> When I start the daemon, i can see some warnings related to QEMU: > >> > >> warning : virQEMUCapsInit:942 : Failed to get host CPU cache info > >> warning : virQEMUCapsInit:949 : Failed to get host power management capabilities > >> > >> Could this be the reason, or the beginning of an explanation ? > >> How can I dig and find what is the root cause ? > > > > Best bet is to edit libvirtd.conf and set > > > > log_filters="1:qemu_capabilities" > > log_outputs="1:file:/var/log/libvirtd.log" > > > > and then rm -rf /var/cache/libvirt/qemu and restart libvirtd. The log > > file should tell you it is detecting qemu-system-x86_64 and probing it. > > If anything fails it should be covered in the logs. > > Thanks, i have more information now: > > debug : virQEMUCapsCacheLookup:4561 : Returning caps (nil) for > /usr/bin/qemu-system-x86_64 > debug : virQEMUCapsCacheLookup:4561 : Returning caps (nil) for /usr/bin/kvm > > Does this help you ? No that just says there's no previous capabiltiies stored in the cache, which is expected since I just told you to delete the cache :-)

Please attach the full debug log, after running 'virsh capabilities'

On Thu, Jun 14, 2018 at 01:23:56PM +0300, Mathieu Tarral wrote: > 2018-06-13 18:23 GMT+03:00 Daniel P. Berrangé <berrange(a)redhat.com&gt;: > > On Wed, Jun 13, 2018 at 06:13:04PM +0300, Mathieu Tarral wrote: > >> 2018-06-13 18:07 GMT+03:00 Daniel P. Berrangé <berrange(a)redhat.com&gt;: > >> > On Wed, Jun 13, 2018 at 05:59:37PM +0300, Mathieu Tarral wrote: > >> >> >> > > >> >> >> > What version of QEMU do you have installed ? Libvirt has recently > >> >> >> > become more aggressive at requiring modern QEMU versions, so its > >> >> >> > possible if your old libvirt was running against old QEMU, that > >> >> >> > might not be supported with new libvirt. > >> >> >> > >> >> >> I'm using QEMU 2.8 here. > >> >> >> That might explain why libvirt cannot find a version that is modern enough. > >> >> > > >> >> > 2.8 is plenty new enough, so that's not the issue. > >> >> > >> >> Alright, so let's focus on libvirt 4.4.0. > >> >> > >> >> When I start the daemon, i can see some warnings related to QEMU: > >> >> > >> >> warning : virQEMUCapsInit:942 : Failed to get host CPU cache info > >> >> warning : virQEMUCapsInit:949 : Failed to get host power management capabilities > >> >> > >> >> Could this be the reason, or the beginning of an explanation ? > >> >> How can I dig and find what is the root cause ? > >> > > >> > Best bet is to edit libvirtd.conf and set > >> > > >> > log_filters="1:qemu_capabilities" > >> > log_outputs="1:file:/var/log/libvirtd.log" > >> > > >> > and then rm -rf /var/cache/libvirt/qemu and restart libvirtd. The log > >> > file should tell you it is detecting qemu-system-x86_64 and probing it. > >> > If anything fails it should be covered in the logs. > >> > >> Thanks, i have more information now: > >> > >> debug : virQEMUCapsCacheLookup:4561 : Returning caps (nil) for > >> /usr/bin/qemu-system-x86_64 > >> debug : virQEMUCapsCacheLookup:4561 : Returning caps (nil) for /usr/bin/kvm > >> > >> Does this help you ? > > > > No that just says there's no previous capabiltiies stored in the cache, > > which is expected since I just told you to delete the cache :-) > > My bad :D > > > Please attach the full debug log, after running 'virsh capabilities' > Sure. > I copy pasted everything in a Github Gist, which is easier to read I think. > https://gist.github.com/Wenzel/805558263b7d6d8b3366a684d5673217 Ok this is the key error: 2018-06-14 10:23:16.994+0000: 31174: error : virCryptoHashBuf:84 : invalid argument: algorithm=1 is not supported it looks like you've built without gnutls, which is a mandatory dep for the QEMU driver. 4.4.0 didn't treat it as mandatory when building, but in git master we've fixed that now so you would see the problem sooner.