Merge pull request #88581 from jhradilek/CNV-47151-vtpm-device-snapshots

CNV-47151: Add information about vTPM device snapshots

Author: jldohmann

modules/virt-about-vtpm-devices.adoc

@@ -8,14 +8,10 @@
 
 A virtual Trusted Platform Module (vTPM) device functions like a
 physical Trusted Platform Module (TPM) hardware chip.
-
 You can use a vTPM device with any operating system, but Windows 11 requires
 the presence of a TPM chip to install or boot. A vTPM device allows VMs created
 from a Windows 11 image to function without a physical TPM chip.
 
-If you do not enable vTPM, then the VM does not recognize a TPM device, even if
-the node has one.
-
 A vTPM device also protects virtual machines by storing secrets without physical hardware. {VirtProductName} supports persisting vTPM device state by using Persistent Volume Claims (PVCs) for VMs. You must specify the storage class to be used by the PVC by setting the `vmStateStorageClass` attribute in the `HyperConverged` custom resource (CR):
 
 [source,yaml]
@@ -29,3 +25,6 @@ spec:
 # ...
 ----
 
+If you do not enable vTPM, then the VM does not recognize a TPM device, even if
+the node has one.
+

virt/creating_vms_advanced/creating_vms_advanced_web/virt-cloning-vms.adoc

@@ -8,6 +8,11 @@ toc::[]
 
 You can clone virtual machines (VMs) or create new VMs from snapshots.
 
+[IMPORTANT]
+====
+Cloning a VM with a vTPM device attached to it or creating a new VM from its snapshot is not supported.
+====
+
 include::modules/virt-cloning-vm-web.adoc[leveloffset=+1]
 
 include::modules/virt-creating-vm-from-snapshot-web.adoc[leveloffset=+1]
@@ -16,4 +21,4 @@ include::modules/virt-creating-vm-from-snapshot-web.adoc[leveloffset=+1]
 [id="additional-resources_{context}"]
 == Additional resources
 
-* xref:../../../virt/creating_vms_advanced/creating_vms_cli/virt-creating-vms-by-cloning-pvcs.adoc#virt-creating-vms-by-cloning-pvcs[Creating VMs by cloning PVCs]
+* xref:../../../virt/creating_vms_advanced/creating_vms_cli/virt-creating-vms-by-cloning-pvcs.adoc#virt-creating-vms-by-cloning-pvcs[Creating VMs by cloning PVCs]

virt/managing_vms/virt-using-vtpm-devices.adoc

@@ -10,5 +10,11 @@ Add a virtual Trusted Platform Module (vTPM) device to a new or existing virtual
 machine by editing the `VirtualMachine` (VM) or `VirtualMachineInstance` (VMI)
 manifest.
 
+[IMPORTANT]
+====
+With {VirtProductName} 4.18 and newer, you can xref:../../virt/managing_vms/virt-exporting-vms.adoc#virt-exporting-vms[export virtual machines] (VMs) with attached vTPM devices, xref:../../virt/backup_restore/virt-backup-restore-snapshots.adoc#creating-snapshots_virt-backup-restore-snapshots[create snapshots of these VMs], and xref:../../virt/backup_restore/virt-backup-restore-snapshots.adoc#restoring-vms-from-snapshots_virt-backup-restore-snapshots[restore VMs from these snapshots]. However, cloning a VM with a vTPM device attached to it or creating a new VM from its snapshot is not supported.
+====
+
 include::modules/virt-about-vtpm-devices.adoc[leveloffset=+1]
+
 include::modules/virt-adding-vtpm-to-vm.adoc[leveloffset=+1]