Comment by stracer
2 years ago
Libvirt and virt-manager are just simplified user interface to the real software, which is qemu(and KVM). They solve pretty trivial problems, like parsing config file and passing the right options to the qemu binary.
Yes, they have some additional useful administration features like start/stop based on a config file, serial console access, but these are really simple to implement in your own shell scripts. Storage handling in libvirt is horrible, verbose, complex, yet it can't even work with thin LVs or ZFS properly.
Unless you just want to run stuff the standard corporate way and do not care about learning fundamental software like qemu and shell, or require some obscure feature of libvirt, I recommend using qemu on KVM directly, using your own scripts. You'll learn more about qemu and less about underwhelming Python wrappers, and you'll have more control on your systems.
Also, IBM/Red Hat seems to have deprecated virt-manager in favour (of course) a new web interface (Copilot).
Quickemu seems to be of more interest, as it allows launching new VM right after a quick look at examples, without time wasting on learning a big complicated UI.
The real advantage to libvirt is that it also works with things other than qemu.
Who uses libvirt with anything else than qemu? Xen has its own much better UI tools, like the xl toolstack, or xcp-ng with Xen orchestra.
If you mean libvirt can provide single UI to different hypervisors, that is true, but I don't see any technical reason to have single UI to different hypervisors. It just provide familiar clicky UI for nontechnical users who do not want to bother with learning hypervisor features and its dedicated tools.
> Quickemu seems to be of more interest, as it allows launching new VM right after a quick look at examples, without time wasting on learning a big complicated UI.
Why would anyone want a qt frontend when you can call a cli wrapper, or better yet the core binary directly?
Libvirt can dump configs as scripts. If virsh/virt-manager does the 90% of the tedious work with a fine UI in order to be replicated later, I guess libvirt wins here.
You've missed the point of libvirtd.
That's possible, but you also seem to have missed mine, which is libvirt is not great time investment if you want to learn how qemu works, or have the most flexibility and control in its deployment.