Description of problem:
Libvirt in the overcloud image ships with Libvirt 4.5.0 while the version installed in the container images is 5.0.0. Functionally this shouldn't create any issue but the VIRSH CLI may behave differently.
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[root@edge0-compute-edge0computehci-0 ~]# rpm -q libvirt-{daemon,client}
libvirt-daemon-4.5.0-24.3.module+el8.0.0+4084+cceb9f44.x86_64
libvirt-client-4.5.0-24.3.module+el8.0.0+4084+cceb9f44.x86_64
[root@edge0-compute-edge0computehci-0 ~]# virsh --version
4.5.0
[root@edge0-compute-edge0computehci-0 ~]# podman exec -it --user root nova_libvirt /bin/bash
()[root@edge0-compute-edge0computehci-0 /]# rpm -q libvirt-{daemon,client}
libvirt-daemon-5.0.0-12.module+el8.0.1+3755+6782b0ed.x86_64
libvirt-client-5.0.0-12.module+el8.0.1+3755+6782b0ed.x86_64
()[root@edge0-compute-edge0computehci-0 /]# virsh --version
5.0.0
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The same type of issue happens also with qemu-img CLI.
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[root@edge1-compute-edge1compute-0 ~]# qemu-img --version
qemu-img version 2.12.0 (qemu-kvm-2.12.0-65.module+el8.0.0+4084+cceb9f44.5)
Copyright (c) 2003-2017 Fabrice Bellard and the QEMU Project developers
[root@edge1-compute-edge1compute-0 ~]# rpm -q qemu-img
qemu-img-2.12.0-65.module+el8.0.0+4084+cceb9f44.5.x86_64
[root@edge1-compute-edge1compute-0 ~]# podman exec -it --user root nova_libvirt /bin/bash
()[root@edge1-compute-edge1compute-0 /]# qemu-img --version
qemu-img version 3.1.0 (qemu-kvm-3.1.0-30.module+el8.0.1+3755+6782b0ed)
Copyright (c) 2003-2018 Fabrice Bellard and the QEMU Project developers
()[root@edge1-compute-edge1compute-0 /]# rpm -q qemu-img
qemu-img-3.1.0-30.module+el8.0.1+3755+6782b0ed.x86_64
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It seems the overcloud images are built without advanced virtualization enabled.

Version-Release number of selected component (if applicable):
OSP15