> - you add to your pull request a change of the virtualized disk
> controller from virtio-blk to virtio-scsi and to the default libvirt
> vagrantfile the "unmap" option so that deletion of blocks in the guest
> are propagated om host storage
I looked into this a bit more. These feature weren't added to
vagrant-libvirt until 0.4.0, so no stable Debian package of
vagrant-libvirt could support this yet. Debian/testing has 0.7.0, and a
backport to stable would be possible. I guess a lot of people just use
`vagrant plugin install ...`. It might be possible to make it work with
older vagrant-libvirt versions by using a hack like this:
https://github.com/vagrant-libvirt/vagrant-libvirt/pull/692#issuecomment-922329049
There is a little more info here:
https://github.com/vagrant-libvirt/vagrant-libvirt/issues/999#issuecomment-487728207
```
ENV['VAGRANT_EXPERIMENTAL'] = 'typed_triggers'
require 'open3'
Vagrant.configure('2') do |config|
...
config.vm.provider :libvirt do |lv, config|
lv.storage :file, :size => '3G', :device => 'sda', :bus => 'scsi',
:discard => 'unmap', :cache => 'unsafe'
config.trigger.before
:'VagrantPlugins::ProviderLibvirt::Action::StartDomain', type: :action
do |trigger|
trigger.ruby do |env, machine|
stdout, stderr, status = Open3.capture3(
'virt-xml', machine.id,
'--edit', 'type=scsi',
'--controller', 'model=virtio-scsi')
if status.exitstatus != 0
raise "failed to run virt-xml to modify the controller model.
status=#{status.exitstatus} stdout=#{stdout} stderr=#{stderr}"
end
end
end
...
end
end
```