[QEMU] Differential disk usage

I want to install a lot of virtual machines with the same configuration. For example, 10 sets of CentOS7, each with a different configuration.

In this case, 10 KVM virtual machines, especially wasted space, image files are not easy to migrate to each other.

You can choose a differential disk at this time: it is a standard CentOS7 installation, as the mother disk. Then put 10 different sub-disks separately, using the following method:

[Email protected] ~/v/host0> qemu-img create-f qcow2-b. /base_centos7_1804/'disk.img', fmt=qcow2 size=1099511627776 backing_ File=. /base_centos7_1804/disk.img cluster_size=65536 lazy_refcounts=off refcount_bits=

As long as you specify the parent disk with-B in the qemu-img, a sub-disk of the differential disk is generated.

[QEMU] Differential disk usage