libvirt
version: 3.4.0
architecture: x86_64 ubuntu16.04-server
hypervisor: kvm,qemu

When migrate vm, I encounter error:
"Migrate VM virt21 failed unsupported configuration: Unable to find security driver for model apparmor"
but two host are same environment.before this error, migrate can be success.
the source host seclabel configure is this :
<seclabel type='dynamic' model='apparmor' relabel='yes'>
    <label>libvirt-8e4ec209-17ca-4b59-abb7-72f3984244f3</label>
    <imagelabel>libvirt-8e4ec209-17ca-4b59-abb7-72f3984244f3</imagelabel>
</seclabel>
I create a vm on the destination host ,the vm configure not seclabel congfigure.
I reinstall libvirt on the destination host and migrate same vm, this error disappear.vm seclabel configure is default.
I recreate a vm on the destination host ,the vm configure has the seclabel configure , I don't known the reason.

Another question:
I configure a vm xml's seclabel like this:
<seclabel type='none' model='none'/>
and then call virDomainCreate create the vm, call virsh dumpxml, the vm xml's seclabel is this:
<seclabel type='none' model='none'/>
<seclabel type='dynamic' model='dac' relabel='yes'>
    <label>+0:+0</label>
    <imagelabel>+0:+0</imagelabel>
</seclabel>
I don't the reason.

Is a vm seclabel configure dynamic change when it running?

Thanks