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--- fuss:libvirt [2018/01/09 18:32] – [Hotswap CD-ROM or Floppy] office
+++ fuss:libvirt [2018/07/27 13:27] – [Create a New Virtual Machine] office
@@ Line 11: / Line 11: @@
 Next, to start the install, run:
 <code bash>
-virt-install --name live --network bridge:br0 --ram 1024 --boot cdrom --cdrom live.iso --graphics vnc,listen=192.168.1.1,port=5901 --disk /var/lib/libvirt/images/live.img
+virt-install --name live \
+    --network bridge:br0 --ram 1024 \
+    --boot cdrom --cdrom live.iso \
+    --graphics vnc,listen=192.168.1.1,port=5901 \
+    --disk /var/lib/libvirt/images/live.img
 </code>
@@ Line 62: / Line 66: @@
 ...
       <model type='virtio'/>
-...
+      <driver>
+        <host gso='off' tso4='off' tso6='off' ecn='off' ufo='off'/>
+        <guest tso4='off' tso6='off' ecn='off'/>
+      </driver>
     </interface>
 </code>
+The ''driver'' block ensures that various offload parameters are turned off for the host and guest which is deemed to be good practice for virtio interfaces on a bridge. Additionally, the bridge can be configured to turn off most of the offloading:
+<code bash>
+ethtool -K br0 tso off sg off ufo off gro off gso off
+</code>
+where:
+  * ''br0'' is the bridge interface to which the virtio interfaces are added.
 ====== Speed-Up Virtualization using Multi-Queue VirtIO Networking ======
@@ Line 600: / Line 616: @@
   * ''vms'' is the libvirt storage pool for the domain ''mydomain.db''.
+====== Passing Plan 9 Permissions ======
+Given a passed-through folder defined in the domain configuration file:
+<code xml>
+    <filesystem type='mount' accessmode='passthrough'>
+      <source dir='/mnt/cdrom'/>
+      <target dir='cd'/>
+    </filesystem>
+</code>
+virtual machines running under ''qemu'' / ''kvm'' have to be started as root. To accomplish that, edit ''/etc/default/libvirt/qemu.conf'' and set:
+<code>
+user = "root"
+group = "root"
+</code>
+Additionally, the following setting:
+<code>
+clear_emulator_capabilities = 0
+</code>
+has to be added to ''/etc/default/libvirt/qemu.conf''.
+Once the virtual machine boots, the share can then be automatically mounted by adding the following line:
+<code>
+cd  /mnt/share     9p      defaults,trans=virtio,version=9p2000.L,posixacl 0       0
+</code>
+to ''/etc/fstab'', where
+  * ''cd'' is the name of the share exposed by the host,
+  * ''/mnt/share'' is the path to a directory where the host share will be mounted,
+  * ''posixacl'' turns on passing POSIX ACLs (very convenient for using ''getfacl'' and ''setfacl'' to fine tune permissions).