I would like to ask a question regarding to disable UFO of virtio vNIC in my guest. I have read the document at https://libvirt.org/formatdomain.html

host

The csum, gso, tso4, tso6, ecn and ufo attributes with possible values on and off can be used to turn off host offloading options. By default, the supported offloads are enabled by QEMU. Since 1.2.9 (QEMU only) The mrg_rxbuf attribute can be used to control mergeable rx buffers on the host side. Possible values are on (default) and off. Since 1.2.13 (QEMU only)

guest

The csum, tso4, tso6, ecn and ufo attributes with possible values on and off can be used to turn off guest offloading options. By default, the supported offloads are enabl

ed by QEMU. Since 1.2.9 (QEMU only)

Then I disabled UFO on my vNIC on guest as the following configuration

<devices>

  <interface type='network'>

    <source network='default'/>

    <target dev='vnet1'/>

    <model type='virtio'/>

    <driver name='vhost' txmode='iothread' ioeventfd='on' event_idx='off' queues='5' rx_queue_size='256' tx_queue_size='256'>

      <host gso='off' ufo='off' />

      <guest ufo='off'/>

    </driver>

   

  </interface>

</devices>

Then I reboot my node to get the change effect and it works. However, can I disable the UFO without touching the host OS? or it always has to disable on both host and guest like that?

Thanks,

Brs,

Natsu