emulated SCSI controller will relay this information to the storage, which will
then shrink the disk image accordingly.
+If you would like a drive to be presented to the guest as a solid-state drive
+rather than a rotational hard disk, you can set the *SSD emulation* option on
+that drive. There is no requirement that the underlying storage actually be
+backed by SSDs; this feature can be used with physical media of any type.
+
.IO Thread
The option *IO Thread* can only be used when using a disk with the
*VirtIO* controller, or with the *SCSI* controller, when the emulated controller
for f in /sys/devices/system/cpu/vulnerabilities/*; do echo "${f##*/} -" $(cat "$f"); done
----
-A community script is also avalaible to detect is the host is still vulnerable.
+A community script is also available to detect is the host is still vulnerable.
footnote:[spectre-meltdown-checker https://meltdown.ovh/]
Intel processors
* 'pcid'
+
-This reduce the performance impact of the Meltdown (CVE-2017-5754) mitigation
+This reduces the performance impact of the Meltdown (CVE-2017-5754) mitigation
called 'Kernel Page-Table Isolation (KPTI)', which effectively hides
the Kernel memory from the user space. Without PCID, KPTI is quite an expensive
mechanism footnote:[PCID is now a critical performance/security feature on x86
* 'spec-ctrl'
+
-Required to enable the Spectre v1 (CVE-2017-5753) and Spectre v2 (CVE-2017-5715) fix,
-in cases where retpolines are not sufficient.
-Included by default in Intel CPU models with -IBRS suffix.
-Must be explicitly turned on for Intel CPU models without -IBRS suffix.
-Requires the host CPU microcode (intel-microcode >= 20180425).
+Required to enable the Spectre v1 (CVE-2017-5753) and Spectre v2 (CVE-2017-5715) fix,
+in cases where retpolines are not sufficient.
+Included by default in Intel CPU models with -IBRS suffix.
+Must be explicitly turned on for Intel CPU models without -IBRS suffix.
+Requires an updated host CPU microcode (intel-microcode >= 20180425).
+
* 'ssbd'
+
-Required to enable the Spectre V4 (CVE-2018-3639) fix. Not included by default in any Intel CPU model.
-Must be explicitly turned on for all Intel CPU models.
-Requires the host CPU microcode(intel-microcode >= 20180703).
+Required to enable the Spectre V4 (CVE-2018-3639) fix. Not included by default in any Intel CPU model.
+Must be explicitly turned on for all Intel CPU models.
+Requires an updated host CPU microcode(intel-microcode >= 20180703).
AMD processors
* 'ibpb'
+
-Required to enable the Spectre v1 (CVE-2017-5753) and Spectre v2 (CVE-2017-5715) fix,
-in cases where retpolines are not sufficient.
-Included by default in AMD CPU models with -IBPB suffix.
-Must be explicitly turned on for AMD CPU models without -IBPB suffix.
+Required to enable the Spectre v1 (CVE-2017-5753) and Spectre v2 (CVE-2017-5715) fix,
+in cases where retpolines are not sufficient.
+Included by default in AMD CPU models with -IBPB suffix.
+Must be explicitly turned on for AMD CPU models without -IBPB suffix.
Requires the host CPU microcode to support this feature before it can be used for guest CPUs.
* 'virt-ssbd'
+
Required to enable the Spectre v4 (CVE-2018-3639) fix.
-Not included by default in any AMD CPU model.
-Must be explicitly turned on for all AMD CPU models.
-This should be provided to guests, even if amd-ssbd is also provided, for maximum guest compatibility.
-Note for some QEMU / libvirt versions, this must be force enabled when when using "Host model",
-because this is a virtual feature that doesn’t exist in the physical host CPUs.
+Not included by default in any AMD CPU model.
+Must be explicitly turned on for all AMD CPU models.
+This should be provided to guests, even if amd-ssbd is also provided, for maximum guest compatibility.
+Note that this must be explicitly enabled when when using the "host" cpu model,
+because this is a virtual feature which does not exist in the physical CPUs.
* 'amd-ssbd'
+
-Required to enable the Spectre v4 (CVE-2018-3639) fix.
-Not included by default in any AMD CPU model. Must be explicitly turned on for all AMD CPU models.
-This provides higher performance than virt-ssbd so should be exposed to guests whenever available in the host.
+Required to enable the Spectre v4 (CVE-2018-3639) fix.
+Not included by default in any AMD CPU model. Must be explicitly turned on for all AMD CPU models.
+This provides higher performance than virt-ssbd, therefore a host supporting this should always expose this to guests if possible.
virt-ssbd should none the less also be exposed for maximum guest compatibility as some kernels only know about virt-ssbd.
* 'amd-no-ssb'
+
Recommended to indicate the host is not vulnerable to Spectre V4 (CVE-2018-3639).
-Not included by default in any AMD CPU model.
-Future hardware generations of CPU will not be vulnerable to CVE-2018-3639,
-and thus the guest should be told not to enable its mitigations, by exposing amd-no-ssb.
+Not included by default in any AMD CPU model.
+Future hardware generations of CPU will not be vulnerable to CVE-2018-3639,
+and thus the guest should be told not to enable its mitigations, by exposing amd-no-ssb.
This is mutually exclusive with virt-ssbd and amd-ssbd.
process a great number of incoming connections, such as when the VM is running
as a router, reverse proxy or a busy HTTP server doing long polling.
+[[qm_display]]
+Display
+~~~~~~~
+
+QEMU can virtualize a few types of VGA hardware. Some examples are:
+
+* *std*, the default, emulates a card with Bochs VBE extensions.
+* *vmware*, is a VMWare SVGA-II compatible adapter.
+* *qxl*, is the QXL paravirtualized graphics card. Selecting this also
+enables SPICE for the VM.
+
+You can edit the amount of memory given to the virtual GPU, by setting
+the *memory* option. This can enable higher resolutions inside the VM,
+especially with SPICE/QXL.
+
+Selecting Multi-Monitor mode for SPICE (e.g., qxl2 for dual monitors) has
+some implications:
+
+* Windows needs a device for each monitor, so if your ostype is some
+version of windows, {pve} gives the VM an extra device per monitor.
+Each device gets the specified amount of memory.
+* Linux VMs, can always enable more virtual monitors, but selecting
+a Multi-Monitor mode multiplies the memory given to the device with
+the number of monitors.
+
+Selecting *serialX* as display disables the VGA output, and redirects
+the Web Console to the selected serial port. A configured memory setting
+will be ignored in that case.
[[qm_usb_passthrough]]
USB Passthrough
Microsoft provides
https://developer.microsoft.com/en-us/windows/downloads/virtual-machines/[Virtual Machines downloads]
- to get started with Windows development.We are going to use one of these
+ to get started with Windows development.We are going to use one of these
to demonstrate the OVF import feature.
Download the Virtual Machine zip
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-After getting informed about the user agreement, choose the _Windows 10
+After getting informed about the user agreement, choose the _Windows 10
Enterprise (Evaluation - Build)_ for the VMware platform, and download the zip.
Extract the disk image from the zip
Adding an external disk image to a Virtual Machine
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-You can also add an existing disk image to a VM, either coming from a
+You can also add an existing disk image to a VM, either coming from a
foreign hypervisor, or one that you created yourself.
Suppose you created a Debian/Ubuntu disk image with the 'vmdebootstrap' tool:
projects / pve-docs.git / blobdiff