This book is _awesome_ I had great fun going through this book and playing with the introduced topics. The book goes really broad, lays some foundations on a massive heap of things while actually going extremely in depth: my favorite subject touched include: concepts of virtualization (paravirt, rings, ..), implementation of KVM in Linux, virtualized networking (vxlan), datacenter storage, vdi devices and procotols (SPICE), dealing with PCI device (vfio-pci), paravirtualized drivers (virtio), tuning kvm (NUMA, SMP, ...).
This has been a wild ride and for this reason 6 stars out of 5, jay !
However, the book still says Packt Publishing, and unfortunately this also shows. The book focuses on CentOS (and esp CentOS 8) which make it feel dated (while it shouldn't !). It also tries to touch some vaguely/somewhat related topics (looking at you Ansible, AWS and OpenStack chapters) but obviously can only do this in a poor way. The entire topic of NUMA is illustrated with screenshots on a system with '1' NUMA node.
But even despite these shortcomings this book is still awesome, just image what it could be when it would've been properly edited.
All avenues covered in order to build and administer a KVM based virtualisation environment. The book is pretty exhaustive and requires the reader has fundamental knowledge in *nix environments, configuration coding and networking.
The one negative is the examples focus on CentOS 8 which is set to go end of life 31 December 2021 - and CentOS stream is deemed more unstable now due to tracking ahead of RHEL.