CentOS - Feb 2019 - question about upgrade qemu and libvirtd

Hi Team,
   I am not sure if I should put my question here, I have googled long
time, no explicit information found.

   Background:
      We need to support KVM encryption and decided to use LUKS.

      Refer to:https://libvirt.org/formatsecret.html#VolumeUsageType

      libvirtd and KVM should be able to support LUKS format disk directly.

      Unfortunately, seems that we need to use libvirt2.2+ and qemu
2.6+, because our current qemu-kvm version does not support luks
format:

      And our hypervisor's OS is CentOS 7.2 with libvirt 2.0 and qemu-kvm
1.5.3

    Question:
       Is there any safe way to upgrade to libvirt 2.2 and qemu 2.6?
       Safe way means: do not need to reboot hyper or VM, do not
impact VM types support .

     Any suggestion is welcome.

Thanks.

On Feb 14, 2019, at 18:23, rong zhao <zhaorbox at gmail.com>
wrote:
> 
> Hi Team,
>   I am not sure if I should put my question here, I have googled long
> time, no explicit information found.
> 
>   Background:
>      We need to support KVM encryption and decided to use LUKS.
> 
>      Refer to:https://libvirt.org/formatsecret.html#VolumeUsageType
> 
>      libvirtd and KVM should be able to support LUKS format disk directly.
> 
>      Unfortunately, seems that we need to use libvirt2.2+ and qemu
> 2.6+, because our current qemu-kvm version does not support luks
> format:
> 
>      And our hypervisor's OS is CentOS 7.2 with libvirt 2.0 and
qemu-kvm 1.5.3
> 
>    Question:
>       Is there any safe way to upgrade to libvirt 2.2 and qemu 2.6?
>       Safe way means: do not need to reboot hyper or VM, do not
> impact VM types support .
> 
>     Any suggestion is welcome.
The libvirt package was update to v2.0 in 7.3.  In the (only supported) latest
release, it?s v4.5.0. Qemu remains at version 1.5.3.

Nonetheless, you won?t be able to upgrade to newer versions without shutting
down or migrating the VMs.

?
Jonathan Billings <billings at negate.org>

On Fri, Feb 15, 2019 at 1:54 AM Jonathan Billings <billings at negate.org>
wrote:
> On Feb 14, 2019, at 18:23, rong zhao <zhaorbox at gmail.com> wrote:
> >
> > Hi Team,
> >   I am not sure if I should put my question here, I have googled long
> > time, no explicit information found.
> >
> >   Background:
> >      We need to support KVM encryption and decided to use LUKS.
> >
> >      Refer to:https://libvirt.org/formatsecret.html#VolumeUsageType
> >
> >      libvirtd and KVM should be able to support LUKS format disk
> directly.
> >
> >      Unfortunately, seems that we need to use libvirt2.2+ and qemu
> > 2.6+, because our current qemu-kvm version does not support luks
> > format:
> >
> >      And our hypervisor's OS is CentOS 7.2 with libvirt 2.0 and
qemu-kvm
> 1.5.3
> >
> >    Question:
> >       Is there any safe way to upgrade to libvirt 2.2 and qemu 2.6?
> >       Safe way means: do not need to reboot hyper or VM, do not
> > impact VM types support .
> >
> >     Any suggestion is welcome.
>
> The libvirt package was update to v2.0 in 7.3.  In the (only supported)
> latest release, it?s v4.5.0. Qemu remains at version 1.5.3.
>
> Nonetheless, you won?t be able to upgrade to newer versions without
> shutting down or migrating the VMs.
>
> ?
> Jonathan Billings <billings at negate.org>
>
>
>
Apart from what already remarked by Jonathan about libvirt being 4.5.0 in
latest upstream CentOS 7.6, released at beginning of December 2018, you can
update to it and then attach to Virtualization SIG and get qemu-kvm-ev, as
shipped for example in RHV/oVirt. It should obsolete qemu-kvm if already
installed. Try on a test system.
Steps to do:

yum-config-manager --enable extras

Now with the command
yum list centos-release-\*

you will see something like:
. . .
centos-release-qemu-ev.noarch               1.0-4.el7.centos
extras
. . .
centos-release-virt-common.noarch           1-1.el7.centos
extras
. . .

and you can execute
yum install centos-release-qemu-ev
(that will bring in also centos-release-virt-common)
Then

yum install qemu-kvm-ev

and it will bring in qemu-kvm-ev in version 2.12.0-18.el7_6.3.1

More info on CentOS SIGs in general and Virtualization one in particular:
https://wiki.centos.org/SpecialInterestGroup
https://wiki.centos.org/SpecialInterestGroup/Virtualization

HIH,
Gianluca