I'm using ubuntu cloud image exclusively in the libvirtd environment, but I'm having trouble selecting the image, so make a note.
Although the OS is the same, the images are slightly different due to the distribution format. For example, at the time of writing, focal amd64 has the following suffix.
For example, Article shows what each of them is, but I was worried about disk-kvm.img.
img is in qcow2 format. disk-kvm.img is also in qcow2 format. When I came to the conclusion of what the difference was, the installed packages were different. You can see that by looking at the diffs in the .manifest file.
--- focal-server-cloudimg-amd64.manifest 2020-12-10 14:21:09.000000000 +0000 +++ focal-server-cloudimg-amd64-disk-kvm.manifest 2020-12-10 14:19:23.000000000 +0000 @@ -354,14 +354,13 @@ libyaml-0-2:amd64 0.2.2-1 libzstd1:amd64 1.4.4+dfsg-3 linux-base 4.5ubuntu3.1 -linux-headers-5.4.0-54 5.4.0-54.60 -linux-headers-5.4.0-54-generic 5.4.0-54.60 -linux-headers-generic 126.96.36.199.57 -linux-headers-virtual 188.8.131.52.57 -linux-image-5.4.0-54-generic 5.4.0-54.60 -linux-image-virtual 184.108.40.206.57 -linux-modules-5.4.0-54-generic 5.4.0-54.60 -linux-virtual 220.127.116.11.57 +linux-headers-5.4.0-1026-kvm 5.4.0-1026.27 +linux-headers-kvm 18.104.22.1686.24 +linux-image-5.4.0-1026-kvm 5.4.0-1026.27 +linux-image-kvm 22.214.171.1246.24 +linux-kvm 126.96.36.1996.24 +linux-kvm-headers-5.4.0-1026 5.4.0-1026.27 +linux-modules-5.4.0-1026-kvm 5.4.0-1026.27 locales 2.31-0ubuntu9.1 login 1:4.8.1-1ubuntu5.20.04 logrotate 3.14.0-4ubuntu3
Seems like the difference between generic and kvm. Just [kernel adjusted for azure](https://ubuntu.com/blog/microsoft-and-canonical-increase-velocity-with-azure-tailored-kernel I haven't followed it in depth, but it seems that Tuning for KVM guests has been applied. This seems to be better for kvm/libvirtd.
But don't forget to set the NIC to ** virtio **.
<interface type="network"><model type="virtio"/></interface>