docs: intro: avoid office@ mail address for sales related questions

[pve-docs.git] / qm.conf.5-opts.adoc

`acpi`: `<boolean>` ('default =' `1`)::

Enable/disable ACPI.

`agent`: `[enabled=]<1|0> [,fstrim_cloned_disks=<1|0>] [,type=<virtio|isa>]` ::

Enable/disable communication with the Qemu Guest Agent and its properties.

`enabled`=`<boolean>` ('default =' `0`);;

Enable/disable communication with a Qemu Guest Agent (QGA) running in the VM.

`fstrim_cloned_disks`=`<boolean>` ('default =' `0`);;

Run fstrim after moving a disk or migrating the VM.

`type`=`<isa | virtio>` ('default =' `virtio`);;

Select the agent type

`arch`: `<aarch64 | x86_64>` ::

Virtual processor architecture. Defaults to the host.

`args`: `<string>` ::

Arbitrary arguments passed to kvm, for example:
+
args: -no-reboot -no-hpet
+
NOTE: this option is for experts only.

`audio0`: `device=<ich9-intel-hda|intel-hda|AC97> [,driver=<spice|none>]` ::

Configure a audio device, useful in combination with QXL/Spice.

`device`=`<AC97 | ich9-intel-hda | intel-hda>` ;;

Configure an audio device.

`driver`=`<none | spice>` ('default =' `spice`);;

Driver backend for the audio device.

`autostart`: `<boolean>` ('default =' `0`)::

Automatic restart after crash (currently ignored).

`balloon`: `<integer> (0 - N)` ::

Amount of target RAM for the VM in MB. Using zero disables the ballon driver.

`bios`: `<ovmf | seabios>` ('default =' `seabios`)::

Select BIOS implementation.

`boot`: `[[legacy=]<[acdn]{1,4}>] [,order=<device[;device...]>]` ::

Specify guest boot order. Use the 'order=' sub-property as usage with no key or 'legacy=' is deprecated.

`legacy`=`<[acdn]{1,4}>` ('default =' `cdn`);;

Boot on floppy (a), hard disk (c), CD-ROM (d), or network (n). Deprecated, use 'order=' instead.

`order`=`<device[;device...]>` ;;

The guest will attempt to boot from devices in the order they appear here.
+
Disks, optical drives and passed-through storage USB devices will be directly
booted from, NICs will load PXE, and PCIe devices will either behave like disks
(e.g. NVMe) or load an option ROM (e.g. RAID controller, hardware NIC).
+
Note that only devices in this list will be marked as bootable and thus loaded
by the guest firmware (BIOS/UEFI). If you require multiple disks for booting
(e.g. software-raid), you need to specify all of them here.
+
Overrides the deprecated 'legacy=[acdn]*' value when given.

`bootdisk`: `(ide|sata|scsi|virtio)\d+` ::

Enable booting from specified disk. Deprecated: Use 'boot: order=foo;bar' instead.

`cdrom`: `<volume>` ::

This is an alias for option -ide2

`cicustom`: `[meta=<volume>] [,network=<volume>] [,user=<volume>] [,vendor=<volume>]` ::

cloud-init: Specify custom files to replace the automatically generated ones at start.

`meta`=`<volume>` ;;

Specify a custom file containing all meta data passed to the VM via"
	    ." cloud-init. This is provider specific meaning configdrive2 and nocloud differ.

`network`=`<volume>` ;;

Specify a custom file containing all network data passed to the VM via cloud-init.

`user`=`<volume>` ;;

Specify a custom file containing all user data passed to the VM via cloud-init.

`vendor`=`<volume>` ;;

Specify a custom file containing all vendor data passed to the VM via cloud-init.

`cipassword`: `<string>` ::

cloud-init: Password to assign the user. Using this is generally not recommended. Use ssh keys instead. Also note that older cloud-init versions do not support hashed passwords.

`citype`: `<configdrive2 | nocloud | opennebula>` ::

Specifies the cloud-init configuration format. The default depends on the configured operating system type (`ostype`. We use the `nocloud` format for Linux, and `configdrive2` for windows.

`ciuser`: `<string>` ::

cloud-init: User name to change ssh keys and password for instead of the image's configured default user.

`cores`: `<integer> (1 - N)` ('default =' `1`)::

The number of cores per socket.

`cpu`: `[[cputype=]<string>] [,flags=<+FLAG[;-FLAG...]>] [,hidden=<1|0>] [,hv-vendor-id=<vendor-id>] [,phys-bits=<8-64|host>] [,reported-model=<enum>]` ::

Emulated CPU type.

`cputype`=`<string>` ('default =' `kvm64`);;

Emulated CPU type. Can be default or custom name (custom model names must be prefixed with 'custom-').

`flags`=`<+FLAG[;-FLAG...]>` ;;

List of additional CPU flags separated by ';'. Use '+FLAG' to enable, '-FLAG' to disable a flag. Custom CPU models can specify any flag supported by QEMU/KVM, VM-specific flags must be from the following set for security reasons: pcid, spec-ctrl, ibpb, ssbd, virt-ssbd, amd-ssbd, amd-no-ssb, pdpe1gb, md-clear, hv-tlbflush, hv-evmcs, aes

`hidden`=`<boolean>` ('default =' `0`);;

Do not identify as a KVM virtual machine.

`hv-vendor-id`=`<vendor-id>` ;;

The Hyper-V vendor ID. Some drivers or programs inside Windows guests need a specific ID.

`phys-bits`=`<8-64|host>` ;;

The physical memory address bits that are reported to the guest OS. Should be smaller or equal to the host's. Set to 'host' to use value from host CPU, but note that doing so will break live migration to CPUs with other values.

`reported-model`=`<486 | Broadwell | Broadwell-IBRS | Broadwell-noTSX | Broadwell-noTSX-IBRS | Cascadelake-Server | Cascadelake-Server-noTSX | Conroe | EPYC | EPYC-IBPB | EPYC-Rome | Haswell | Haswell-IBRS | Haswell-noTSX | Haswell-noTSX-IBRS | Icelake-Client | Icelake-Client-noTSX | Icelake-Server | Icelake-Server-noTSX | IvyBridge | IvyBridge-IBRS | KnightsMill | Nehalem | Nehalem-IBRS | Opteron_G1 | Opteron_G2 | Opteron_G3 | Opteron_G4 | Opteron_G5 | Penryn | SandyBridge | SandyBridge-IBRS | Skylake-Client | Skylake-Client-IBRS | Skylake-Client-noTSX-IBRS | Skylake-Server | Skylake-Server-IBRS | Skylake-Server-noTSX-IBRS | Westmere | Westmere-IBRS | athlon | core2duo | coreduo | host | kvm32 | kvm64 | max | pentium | pentium2 | pentium3 | phenom | qemu32 | qemu64>` ('default =' `kvm64`);;

CPU model and vendor to report to the guest. Must be a QEMU/KVM supported model. Only valid for custom CPU model definitions, default models will always report themselves to the guest OS.

`cpulimit`: `<number> (0 - 128)` ('default =' `0`)::

Limit of CPU usage.
+
NOTE: If the computer has 2 CPUs, it has total of '2' CPU time. Value '0' indicates no CPU limit.

`cpuunits`: `<integer> (1 - 262144)` ('default =' `cgroup v1: 1024, cgroup v2: 100`)::

CPU weight for a VM. Argument is used in the kernel fair scheduler. The larger the number is, the more CPU time this VM gets. Number is relative to weights of all the other running VMs.

`description`: `<string>` ::

Description for the VM. Shown in the web-interface VM's summary. This is saved as comment inside the configuration file.

`efidisk0`: `[file=]<volume> [,efitype=<2m|4m>] [,format=<enum>] [,pre-enrolled-keys=<1|0>] [,size=<DiskSize>]` ::

Configure a Disk for storing EFI vars.

`efitype`=`<2m | 4m>` ('default =' `2m`);;

Size and type of the OVMF EFI vars. '4m' is newer and recommended, and required for Secure Boot. For backwards compatibility, '2m' is used if not otherwise specified.

`file`=`<volume>` ;;

The drive's backing volume.

`format`=`<cloop | cow | qcow | qcow2 | qed | raw | vmdk>` ;;

The drive's backing file's data format.

`pre-enrolled-keys`=`<boolean>` ('default =' `0`);;

Use am EFI vars template with distribution-specific and Microsoft Standard keys enrolled, if used with 'efitype=4m'. Note that this will enable Secure Boot by default, though it can still be turned off from within the VM.

`size`=`<DiskSize>` ;;

Disk size. This is purely informational and has no effect.

`freeze`: `<boolean>` ::

Freeze CPU at startup (use 'c' monitor command to start execution).

`hookscript`: `<string>` ::

Script that will be executed during various steps in the vms lifetime.

`hostpci[n]`: `[host=]<HOSTPCIID[;HOSTPCIID2...]> [,device-id=<hex id>] [,legacy-igd=<1|0>] [,mdev=<string>] [,pcie=<1|0>] [,rombar=<1|0>] [,romfile=<string>] [,sub-device-id=<hex id>] [,sub-vendor-id=<hex id>] [,vendor-id=<hex id>] [,x-vga=<1|0>]` ::

Map host PCI devices into guest.
+
NOTE: This option allows direct access to host hardware. So it is no longer
possible to migrate such machines - use with special care.
+
CAUTION: Experimental! User reported problems with this option.

`device-id`=`<hex id>` ;;

Override PCI device ID visible to guest

`host`=`<HOSTPCIID[;HOSTPCIID2...]>` ;;

Host PCI device pass through. The PCI ID of a host's PCI device or a list
of PCI virtual functions of the host. HOSTPCIID syntax is:
+
'bus:dev.func' (hexadecimal numbers)
+
You can us the 'lspci' command to list existing PCI devices.

`legacy-igd`=`<boolean>` ('default =' `0`);;

Pass this device in legacy IGD mode, making it the primary and exclusive graphics device in the VM. Requires 'pc-i440fx' machine type and VGA set to 'none'.

`mdev`=`<string>` ;;

The type of mediated device to use.
An instance of this type will be created on startup of the VM and
will be cleaned up when the VM stops.

`pcie`=`<boolean>` ('default =' `0`);;

Choose the PCI-express bus (needs the 'q35' machine model).

`rombar`=`<boolean>` ('default =' `1`);;

Specify whether or not the device's ROM will be visible in the guest's memory map.

`romfile`=`<string>` ;;

Custom pci device rom filename (must be located in /usr/share/kvm/).

`sub-device-id`=`<hex id>` ;;

Override PCI subsystem device ID visible to guest

`sub-vendor-id`=`<hex id>` ;;

Override PCI subsystem vendor ID visible to guest

`vendor-id`=`<hex id>` ;;

Override PCI vendor ID visible to guest

`x-vga`=`<boolean>` ('default =' `0`);;

Enable vfio-vga device support.

`hotplug`: `<string>` ('default =' `network,disk,usb`)::

Selectively enable hotplug features. This is a comma separated list of hotplug features: 'network', 'disk', 'cpu', 'memory' and 'usb'. Use '0' to disable hotplug completely. Using '1' as value is an alias for the default `network,disk,usb`.

`hugepages`: `<1024 | 2 | any>` ::

Enable/disable hugepages memory.

`ide[n]`: `[file=]<volume> [,aio=<native|threads|io_uring>] [,backup=<1|0>] [,bps=<bps>] [,bps_max_length=<seconds>] [,bps_rd=<bps>] [,bps_rd_max_length=<seconds>] [,bps_wr=<bps>] [,bps_wr_max_length=<seconds>] [,cache=<enum>] [,cyls=<integer>] [,detect_zeroes=<1|0>] [,discard=<ignore|on>] [,format=<enum>] [,heads=<integer>] [,iops=<iops>] [,iops_max=<iops>] [,iops_max_length=<seconds>] [,iops_rd=<iops>] [,iops_rd_max=<iops>] [,iops_rd_max_length=<seconds>] [,iops_wr=<iops>] [,iops_wr_max=<iops>] [,iops_wr_max_length=<seconds>] [,mbps=<mbps>] [,mbps_max=<mbps>] [,mbps_rd=<mbps>] [,mbps_rd_max=<mbps>] [,mbps_wr=<mbps>] [,mbps_wr_max=<mbps>] [,media=<cdrom|disk>] [,model=<model>] [,replicate=<1|0>] [,rerror=<ignore|report|stop>] [,secs=<integer>] [,serial=<serial>] [,shared=<1|0>] [,size=<DiskSize>] [,snapshot=<1|0>] [,ssd=<1|0>] [,trans=<none|lba|auto>] [,werror=<enum>] [,wwn=<wwn>]` ::

Use volume as IDE hard disk or CD-ROM (n is 0 to 3).

`aio`=`<io_uring | native | threads>` ;;

AIO type to use.

`backup`=`<boolean>` ;;

Whether the drive should be included when making backups.

`bps`=`<bps>` ;;

Maximum r/w speed in bytes per second.

`bps_max_length`=`<seconds>` ;;

Maximum length of I/O bursts in seconds.

`bps_rd`=`<bps>` ;;

Maximum read speed in bytes per second.

`bps_rd_max_length`=`<seconds>` ;;

Maximum length of read I/O bursts in seconds.

`bps_wr`=`<bps>` ;;

Maximum write speed in bytes per second.

`bps_wr_max_length`=`<seconds>` ;;

Maximum length of write I/O bursts in seconds.

`cache`=`<directsync | none | unsafe | writeback | writethrough>` ;;

The drive's cache mode

`cyls`=`<integer>` ;;

Force the drive's physical geometry to have a specific cylinder count.

`detect_zeroes`=`<boolean>` ;;

Controls whether to detect and try to optimize writes of zeroes.

`discard`=`<ignore | on>` ;;

Controls whether to pass discard/trim requests to the underlying storage.

`file`=`<volume>` ;;

The drive's backing volume.

`format`=`<cloop | cow | qcow | qcow2 | qed | raw | vmdk>` ;;

The drive's backing file's data format.

`heads`=`<integer>` ;;

Force the drive's physical geometry to have a specific head count.

`iops`=`<iops>` ;;

Maximum r/w I/O in operations per second.

`iops_max`=`<iops>` ;;

Maximum unthrottled r/w I/O pool in operations per second.

`iops_max_length`=`<seconds>` ;;

Maximum length of I/O bursts in seconds.

`iops_rd`=`<iops>` ;;

Maximum read I/O in operations per second.

`iops_rd_max`=`<iops>` ;;

Maximum unthrottled read I/O pool in operations per second.

`iops_rd_max_length`=`<seconds>` ;;

Maximum length of read I/O bursts in seconds.

`iops_wr`=`<iops>` ;;

Maximum write I/O in operations per second.

`iops_wr_max`=`<iops>` ;;

Maximum unthrottled write I/O pool in operations per second.

`iops_wr_max_length`=`<seconds>` ;;

Maximum length of write I/O bursts in seconds.

`mbps`=`<mbps>` ;;

Maximum r/w speed in megabytes per second.

`mbps_max`=`<mbps>` ;;

Maximum unthrottled r/w pool in megabytes per second.

`mbps_rd`=`<mbps>` ;;

Maximum read speed in megabytes per second.

`mbps_rd_max`=`<mbps>` ;;

Maximum unthrottled read pool in megabytes per second.

`mbps_wr`=`<mbps>` ;;

Maximum write speed in megabytes per second.

`mbps_wr_max`=`<mbps>` ;;

Maximum unthrottled write pool in megabytes per second.

`media`=`<cdrom | disk>` ('default =' `disk`);;

The drive's media type.

`model`=`<model>` ;;

The drive's reported model name, url-encoded, up to 40 bytes long.

`replicate`=`<boolean>` ('default =' `1`);;

Whether the drive should considered for replication jobs.

`rerror`=`<ignore | report | stop>` ;;

Read error action.

`secs`=`<integer>` ;;

Force the drive's physical geometry to have a specific sector count.

`serial`=`<serial>` ;;

The drive's reported serial number, url-encoded, up to 20 bytes long.

`shared`=`<boolean>` ('default =' `0`);;

Mark this locally-managed volume as available on all nodes.
+
WARNING: This option does not share the volume automatically, it assumes it is shared already!

`size`=`<DiskSize>` ;;

Disk size. This is purely informational and has no effect.

`snapshot`=`<boolean>` ;;

Controls qemu's snapshot mode feature. If activated, changes made to the disk are temporary and will be discarded when the VM is shutdown.

`ssd`=`<boolean>` ;;

Whether to expose this drive as an SSD, rather than a rotational hard disk.

`trans`=`<auto | lba | none>` ;;

Force disk geometry bios translation mode.

`werror`=`<enospc | ignore | report | stop>` ;;

Write error action.

`wwn`=`<wwn>` ;;

The drive's worldwide name, encoded as 16 bytes hex string, prefixed by '0x'.

`ipconfig[n]`: `[gw=<GatewayIPv4>] [,gw6=<GatewayIPv6>] [,ip=<IPv4Format/CIDR>] [,ip6=<IPv6Format/CIDR>]` ::

cloud-init: Specify IP addresses and gateways for the corresponding interface.
+
IP addresses use CIDR notation, gateways are optional but need an IP of the same type specified.
+
The special string 'dhcp' can be used for IP addresses to use DHCP, in which case no explicit
gateway should be provided.
For IPv6 the special string 'auto' can be used to use stateless autoconfiguration. This requires
cloud-init 19.4 or newer.
+
If cloud-init is enabled and neither an IPv4 nor an IPv6 address is specified, it defaults to using
dhcp on IPv4.

`gw`=`<GatewayIPv4>` ;;

Default gateway for IPv4 traffic.
+
NOTE: Requires option(s): `ip`

`gw6`=`<GatewayIPv6>` ;;

Default gateway for IPv6 traffic.
+
NOTE: Requires option(s): `ip6`

`ip`=`<IPv4Format/CIDR>` ('default =' `dhcp`);;

IPv4 address in CIDR format.

`ip6`=`<IPv6Format/CIDR>` ('default =' `dhcp`);;

IPv6 address in CIDR format.

`ivshmem`: `size=<integer> [,name=<string>]` ::

Inter-VM shared memory. Useful for direct communication between VMs, or to the host.

`name`=`<string>` ;;

The name of the file. Will be prefixed with 'pve-shm-'. Default is the VMID. Will be deleted when the VM is stopped.

`size`=`<integer> (1 - N)` ;;

The size of the file in MB.

`keephugepages`: `<boolean>` ('default =' `0`)::

Use together with hugepages. If enabled, hugepages will not not be deleted after VM shutdown and can be used for subsequent starts.

`keyboard`: `<da | de | de-ch | en-gb | en-us | es | fi | fr | fr-be | fr-ca | fr-ch | hu | is | it | ja | lt | mk | nl | no | pl | pt | pt-br | sl | sv | tr>` ::

Keyboard layout for VNC server. This option is generally not required and is often better handled from within the guest OS.

`kvm`: `<boolean>` ('default =' `1`)::

Enable/disable KVM hardware virtualization.

`localtime`: `<boolean>` ::

Set the real time clock (RTC) to local time. This is enabled by default if the `ostype` indicates a Microsoft Windows OS.

`lock`: `<backup | clone | create | migrate | rollback | snapshot | snapshot-delete | suspended | suspending>` ::

Lock/unlock the VM.

`machine`: `(pc|pc(-i440fx)?-\d+(\.\d+)+(\+pve\d+)?(\.pxe)?|q35|pc-q35-\d+(\.\d+)+(\+pve\d+)?(\.pxe)?|virt(?:-\d+(\.\d+)+)?(\+pve\d+)?)` ::

Specifies the Qemu machine type.

`memory`: `<integer> (16 - N)` ('default =' `512`)::

Amount of RAM for the VM in MB. This is the maximum available memory when you use the balloon device.

`migrate_downtime`: `<number> (0 - N)` ('default =' `0.1`)::

Set maximum tolerated downtime (in seconds) for migrations.

`migrate_speed`: `<integer> (0 - N)` ('default =' `0`)::

Set maximum speed (in MB/s) for migrations. Value 0 is no limit.

`name`: `<string>` ::

Set a name for the VM. Only used on the configuration web interface.

`nameserver`: `<string>` ::

cloud-init: Sets DNS server IP address for a container. Create will'
	    .' automatically use the setting from the host if neither searchdomain nor nameserver'
	    .' are set.

`net[n]`: `[model=]<enum> [,bridge=<bridge>] [,firewall=<1|0>] [,link_down=<1|0>] [,macaddr=<XX:XX:XX:XX:XX:XX>] [,mtu=<integer>] [,queues=<integer>] [,rate=<number>] [,tag=<integer>] [,trunks=<vlanid[;vlanid...]>] [,<model>=<macaddr>]` ::

Specify network devices.

`bridge`=`<bridge>` ;;

Bridge to attach the network device to. The Proxmox VE standard bridge
is called 'vmbr0'.
+
If you do not specify a bridge, we create a kvm user (NATed) network
device, which provides DHCP and DNS services. The following addresses
are used:
+
 10.0.2.2   Gateway
 10.0.2.3   DNS Server
 10.0.2.4   SMB Server
+
The DHCP server assign addresses to the guest starting from 10.0.2.15.

`firewall`=`<boolean>` ;;

Whether this interface should be protected by the firewall.

`link_down`=`<boolean>` ;;

Whether this interface should be disconnected (like pulling the plug).

`macaddr`=`<XX:XX:XX:XX:XX:XX>` ;;

A common MAC address with the I/G (Individual/Group) bit not set.

`model`=`<e1000 | e1000-82540em | e1000-82544gc | e1000-82545em | e1000e | i82551 | i82557b | i82559er | ne2k_isa | ne2k_pci | pcnet | rtl8139 | virtio | vmxnet3>` ;;

Network Card Model. The 'virtio' model provides the best performance with very low CPU overhead. If your guest does not support this driver, it is usually best to use 'e1000'.

`mtu`=`<integer> (1 - 65520)` ;;

Force MTU, for VirtIO only. Set to '1' to use the bridge MTU

`queues`=`<integer> (0 - 16)` ;;

Number of packet queues to be used on the device.

`rate`=`<number> (0 - N)` ;;

Rate limit in mbps (megabytes per second) as floating point number.

`tag`=`<integer> (1 - 4094)` ;;

VLAN tag to apply to packets on this interface.

`trunks`=`<vlanid[;vlanid...]>` ;;

VLAN trunks to pass through this interface.

`numa`: `<boolean>` ('default =' `0`)::

Enable/disable NUMA.

`numa[n]`: `cpus=<id[-id];...> [,hostnodes=<id[-id];...>] [,memory=<number>] [,policy=<preferred|bind|interleave>]` ::

NUMA topology.

`cpus`=`<id[-id];...>` ;;

CPUs accessing this NUMA node.

`hostnodes`=`<id[-id];...>` ;;

Host NUMA nodes to use.

`memory`=`<number>` ;;

Amount of memory this NUMA node provides.

`policy`=`<bind | interleave | preferred>` ;;

NUMA allocation policy.

`onboot`: `<boolean>` ('default =' `0`)::

Specifies whether a VM will be started during system bootup.

`ostype`: `<l24 | l26 | other | solaris | w2k | w2k3 | w2k8 | win10 | win11 | win7 | win8 | wvista | wxp>` ::

Specify guest operating system. This is used to enable special
optimization/features for specific operating systems:
+
[horizontal]
other;; unspecified OS
wxp;; Microsoft Windows XP
w2k;; Microsoft Windows 2000
w2k3;; Microsoft Windows 2003
w2k8;; Microsoft Windows 2008
wvista;; Microsoft Windows Vista
win7;; Microsoft Windows 7
win8;; Microsoft Windows 8/2012/2012r2
win10;; Microsoft Windows 10/2016/2019
win11;; Microsoft Windows 11/2022
l24;; Linux 2.4 Kernel
l26;; Linux 2.6 - 5.X Kernel
solaris;; Solaris/OpenSolaris/OpenIndiania kernel

`parallel[n]`: `/dev/parport\d+|/dev/usb/lp\d+` ::

Map host parallel devices (n is 0 to 2).
+
NOTE: This option allows direct access to host hardware. So it is no longer possible to migrate such
machines - use with special care.
+
CAUTION: Experimental! User reported problems with this option.

`protection`: `<boolean>` ('default =' `0`)::

Sets the protection flag of the VM. This will disable the remove VM and remove disk operations.

`reboot`: `<boolean>` ('default =' `1`)::

Allow reboot. If set to '0' the VM exit on reboot.

`rng0`: `[source=]</dev/urandom|/dev/random|/dev/hwrng> [,max_bytes=<integer>] [,period=<integer>]` ::

Configure a VirtIO-based Random Number Generator.

`max_bytes`=`<integer>` ('default =' `1024`);;

Maximum bytes of entropy allowed to get injected into the guest every 'period' milliseconds. Prefer a lower value when using '/dev/random' as source. Use `0` to disable limiting (potentially dangerous!).

`period`=`<integer>` ('default =' `1000`);;

Every 'period' milliseconds the entropy-injection quota is reset, allowing the guest to retrieve another 'max_bytes' of entropy.

`source`=`</dev/hwrng | /dev/random | /dev/urandom>` ;;

The file on the host to gather entropy from. In most cases '/dev/urandom' should be preferred over '/dev/random' to avoid entropy-starvation issues on the host. Using urandom does *not* decrease security in any meaningful way, as it's still seeded from real entropy, and the bytes provided will most likely be mixed with real entropy on the guest as well. '/dev/hwrng' can be used to pass through a hardware RNG from the host.

`sata[n]`: `[file=]<volume> [,aio=<native|threads|io_uring>] [,backup=<1|0>] [,bps=<bps>] [,bps_max_length=<seconds>] [,bps_rd=<bps>] [,bps_rd_max_length=<seconds>] [,bps_wr=<bps>] [,bps_wr_max_length=<seconds>] [,cache=<enum>] [,cyls=<integer>] [,detect_zeroes=<1|0>] [,discard=<ignore|on>] [,format=<enum>] [,heads=<integer>] [,iops=<iops>] [,iops_max=<iops>] [,iops_max_length=<seconds>] [,iops_rd=<iops>] [,iops_rd_max=<iops>] [,iops_rd_max_length=<seconds>] [,iops_wr=<iops>] [,iops_wr_max=<iops>] [,iops_wr_max_length=<seconds>] [,mbps=<mbps>] [,mbps_max=<mbps>] [,mbps_rd=<mbps>] [,mbps_rd_max=<mbps>] [,mbps_wr=<mbps>] [,mbps_wr_max=<mbps>] [,media=<cdrom|disk>] [,replicate=<1|0>] [,rerror=<ignore|report|stop>] [,secs=<integer>] [,serial=<serial>] [,shared=<1|0>] [,size=<DiskSize>] [,snapshot=<1|0>] [,ssd=<1|0>] [,trans=<none|lba|auto>] [,werror=<enum>] [,wwn=<wwn>]` ::

Use volume as SATA hard disk or CD-ROM (n is 0 to 5).

`aio`=`<io_uring | native | threads>` ;;

AIO type to use.

`backup`=`<boolean>` ;;

Whether the drive should be included when making backups.

`bps`=`<bps>` ;;

Maximum r/w speed in bytes per second.

`bps_max_length`=`<seconds>` ;;

Maximum length of I/O bursts in seconds.

`bps_rd`=`<bps>` ;;

Maximum read speed in bytes per second.

`bps_rd_max_length`=`<seconds>` ;;

Maximum length of read I/O bursts in seconds.

`bps_wr`=`<bps>` ;;

Maximum write speed in bytes per second.

`bps_wr_max_length`=`<seconds>` ;;

Maximum length of write I/O bursts in seconds.

`cache`=`<directsync | none | unsafe | writeback | writethrough>` ;;

The drive's cache mode

`cyls`=`<integer>` ;;

Force the drive's physical geometry to have a specific cylinder count.

`detect_zeroes`=`<boolean>` ;;

Controls whether to detect and try to optimize writes of zeroes.

`discard`=`<ignore | on>` ;;

Controls whether to pass discard/trim requests to the underlying storage.

`file`=`<volume>` ;;

The drive's backing volume.

`format`=`<cloop | cow | qcow | qcow2 | qed | raw | vmdk>` ;;

The drive's backing file's data format.

`heads`=`<integer>` ;;

Force the drive's physical geometry to have a specific head count.

`iops`=`<iops>` ;;

Maximum r/w I/O in operations per second.

`iops_max`=`<iops>` ;;

Maximum unthrottled r/w I/O pool in operations per second.

`iops_max_length`=`<seconds>` ;;

Maximum length of I/O bursts in seconds.

`iops_rd`=`<iops>` ;;

Maximum read I/O in operations per second.

`iops_rd_max`=`<iops>` ;;

Maximum unthrottled read I/O pool in operations per second.

`iops_rd_max_length`=`<seconds>` ;;

Maximum length of read I/O bursts in seconds.

`iops_wr`=`<iops>` ;;

Maximum write I/O in operations per second.

`iops_wr_max`=`<iops>` ;;

Maximum unthrottled write I/O pool in operations per second.

`iops_wr_max_length`=`<seconds>` ;;

Maximum length of write I/O bursts in seconds.

`mbps`=`<mbps>` ;;

Maximum r/w speed in megabytes per second.

`mbps_max`=`<mbps>` ;;

Maximum unthrottled r/w pool in megabytes per second.

`mbps_rd`=`<mbps>` ;;

Maximum read speed in megabytes per second.

`mbps_rd_max`=`<mbps>` ;;

Maximum unthrottled read pool in megabytes per second.

`mbps_wr`=`<mbps>` ;;

Maximum write speed in megabytes per second.

`mbps_wr_max`=`<mbps>` ;;

Maximum unthrottled write pool in megabytes per second.

`media`=`<cdrom | disk>` ('default =' `disk`);;

The drive's media type.

`replicate`=`<boolean>` ('default =' `1`);;

Whether the drive should considered for replication jobs.

`rerror`=`<ignore | report | stop>` ;;

Read error action.

`secs`=`<integer>` ;;

Force the drive's physical geometry to have a specific sector count.

`serial`=`<serial>` ;;

The drive's reported serial number, url-encoded, up to 20 bytes long.

`shared`=`<boolean>` ('default =' `0`);;

Mark this locally-managed volume as available on all nodes.
+
WARNING: This option does not share the volume automatically, it assumes it is shared already!

`size`=`<DiskSize>` ;;

Disk size. This is purely informational and has no effect.

`snapshot`=`<boolean>` ;;

Controls qemu's snapshot mode feature. If activated, changes made to the disk are temporary and will be discarded when the VM is shutdown.

`ssd`=`<boolean>` ;;

Whether to expose this drive as an SSD, rather than a rotational hard disk.

`trans`=`<auto | lba | none>` ;;

Force disk geometry bios translation mode.

`werror`=`<enospc | ignore | report | stop>` ;;

Write error action.

`wwn`=`<wwn>` ;;

The drive's worldwide name, encoded as 16 bytes hex string, prefixed by '0x'.

`scsi[n]`: `[file=]<volume> [,aio=<native|threads|io_uring>] [,backup=<1|0>] [,bps=<bps>] [,bps_max_length=<seconds>] [,bps_rd=<bps>] [,bps_rd_max_length=<seconds>] [,bps_wr=<bps>] [,bps_wr_max_length=<seconds>] [,cache=<enum>] [,cyls=<integer>] [,detect_zeroes=<1|0>] [,discard=<ignore|on>] [,format=<enum>] [,heads=<integer>] [,iops=<iops>] [,iops_max=<iops>] [,iops_max_length=<seconds>] [,iops_rd=<iops>] [,iops_rd_max=<iops>] [,iops_rd_max_length=<seconds>] [,iops_wr=<iops>] [,iops_wr_max=<iops>] [,iops_wr_max_length=<seconds>] [,iothread=<1|0>] [,mbps=<mbps>] [,mbps_max=<mbps>] [,mbps_rd=<mbps>] [,mbps_rd_max=<mbps>] [,mbps_wr=<mbps>] [,mbps_wr_max=<mbps>] [,media=<cdrom|disk>] [,queues=<integer>] [,replicate=<1|0>] [,rerror=<ignore|report|stop>] [,ro=<1|0>] [,scsiblock=<1|0>] [,secs=<integer>] [,serial=<serial>] [,shared=<1|0>] [,size=<DiskSize>] [,snapshot=<1|0>] [,ssd=<1|0>] [,trans=<none|lba|auto>] [,werror=<enum>] [,wwn=<wwn>]` ::

Use volume as SCSI hard disk or CD-ROM (n is 0 to 30).

`aio`=`<io_uring | native | threads>` ;;

AIO type to use.

`backup`=`<boolean>` ;;

Whether the drive should be included when making backups.

`bps`=`<bps>` ;;

Maximum r/w speed in bytes per second.

`bps_max_length`=`<seconds>` ;;

Maximum length of I/O bursts in seconds.

`bps_rd`=`<bps>` ;;

Maximum read speed in bytes per second.

`bps_rd_max_length`=`<seconds>` ;;

Maximum length of read I/O bursts in seconds.

`bps_wr`=`<bps>` ;;

Maximum write speed in bytes per second.

`bps_wr_max_length`=`<seconds>` ;;

Maximum length of write I/O bursts in seconds.

`cache`=`<directsync | none | unsafe | writeback | writethrough>` ;;

The drive's cache mode

`cyls`=`<integer>` ;;

Force the drive's physical geometry to have a specific cylinder count.

`detect_zeroes`=`<boolean>` ;;

Controls whether to detect and try to optimize writes of zeroes.

`discard`=`<ignore | on>` ;;

Controls whether to pass discard/trim requests to the underlying storage.

`file`=`<volume>` ;;

The drive's backing volume.

`format`=`<cloop | cow | qcow | qcow2 | qed | raw | vmdk>` ;;

The drive's backing file's data format.

`heads`=`<integer>` ;;

Force the drive's physical geometry to have a specific head count.

`iops`=`<iops>` ;;

Maximum r/w I/O in operations per second.

`iops_max`=`<iops>` ;;

Maximum unthrottled r/w I/O pool in operations per second.

`iops_max_length`=`<seconds>` ;;

Maximum length of I/O bursts in seconds.

`iops_rd`=`<iops>` ;;

Maximum read I/O in operations per second.

`iops_rd_max`=`<iops>` ;;

Maximum unthrottled read I/O pool in operations per second.

`iops_rd_max_length`=`<seconds>` ;;

Maximum length of read I/O bursts in seconds.

`iops_wr`=`<iops>` ;;

Maximum write I/O in operations per second.

`iops_wr_max`=`<iops>` ;;

Maximum unthrottled write I/O pool in operations per second.

`iops_wr_max_length`=`<seconds>` ;;

Maximum length of write I/O bursts in seconds.

`iothread`=`<boolean>` ;;

Whether to use iothreads for this drive

`mbps`=`<mbps>` ;;

Maximum r/w speed in megabytes per second.

`mbps_max`=`<mbps>` ;;

Maximum unthrottled r/w pool in megabytes per second.

`mbps_rd`=`<mbps>` ;;

Maximum read speed in megabytes per second.

`mbps_rd_max`=`<mbps>` ;;

Maximum unthrottled read pool in megabytes per second.

`mbps_wr`=`<mbps>` ;;

Maximum write speed in megabytes per second.

`mbps_wr_max`=`<mbps>` ;;

Maximum unthrottled write pool in megabytes per second.

`media`=`<cdrom | disk>` ('default =' `disk`);;

The drive's media type.

`queues`=`<integer> (2 - N)` ;;

Number of queues.

`replicate`=`<boolean>` ('default =' `1`);;

Whether the drive should considered for replication jobs.

`rerror`=`<ignore | report | stop>` ;;

Read error action.

`ro`=`<boolean>` ;;

Whether the drive is read-only.

`scsiblock`=`<boolean>` ('default =' `0`);;

whether to use scsi-block for full passthrough of host block device
+
WARNING: can lead to I/O errors in combination with low memory or high memory fragmentation on host

`secs`=`<integer>` ;;

Force the drive's physical geometry to have a specific sector count.

`serial`=`<serial>` ;;

The drive's reported serial number, url-encoded, up to 20 bytes long.

`shared`=`<boolean>` ('default =' `0`);;

Mark this locally-managed volume as available on all nodes.
+
WARNING: This option does not share the volume automatically, it assumes it is shared already!

`size`=`<DiskSize>` ;;

Disk size. This is purely informational and has no effect.

`snapshot`=`<boolean>` ;;

Controls qemu's snapshot mode feature. If activated, changes made to the disk are temporary and will be discarded when the VM is shutdown.

`ssd`=`<boolean>` ;;

Whether to expose this drive as an SSD, rather than a rotational hard disk.

`trans`=`<auto | lba | none>` ;;

Force disk geometry bios translation mode.

`werror`=`<enospc | ignore | report | stop>` ;;

Write error action.

`wwn`=`<wwn>` ;;

The drive's worldwide name, encoded as 16 bytes hex string, prefixed by '0x'.

`scsihw`: `<lsi | lsi53c810 | megasas | pvscsi | virtio-scsi-pci | virtio-scsi-single>` ('default =' `lsi`)::

SCSI controller model

`searchdomain`: `<string>` ::

cloud-init: Sets DNS search domains for a container. Create will'
	    .' automatically use the setting from the host if neither searchdomain nor nameserver'
	    .' are set.

`serial[n]`: `(/dev/.+|socket)` ::

Create a serial device inside the VM (n is 0 to 3), and pass through a
host serial device (i.e. /dev/ttyS0), or create a unix socket on the
host side (use 'qm terminal' to open a terminal connection).
+
NOTE: If you pass through a host serial device, it is no longer possible to migrate such machines -
use with special care.
+
CAUTION: Experimental! User reported problems with this option.

`shares`: `<integer> (0 - 50000)` ('default =' `1000`)::

Amount of memory shares for auto-ballooning. The larger the number is, the more memory this VM gets. Number is relative to weights of all other running VMs. Using zero disables auto-ballooning. Auto-ballooning is done by pvestatd.

`smbios1`: `[base64=<1|0>] [,family=<Base64 encoded string>] [,manufacturer=<Base64 encoded string>] [,product=<Base64 encoded string>] [,serial=<Base64 encoded string>] [,sku=<Base64 encoded string>] [,uuid=<UUID>] [,version=<Base64 encoded string>]` ::

Specify SMBIOS type 1 fields.

`base64`=`<boolean>` ;;

Flag to indicate that the SMBIOS values are base64 encoded

`family`=`<Base64 encoded string>` ;;

Set SMBIOS1 family string.

`manufacturer`=`<Base64 encoded string>` ;;

Set SMBIOS1 manufacturer.

`product`=`<Base64 encoded string>` ;;

Set SMBIOS1 product ID.

`serial`=`<Base64 encoded string>` ;;

Set SMBIOS1 serial number.

`sku`=`<Base64 encoded string>` ;;

Set SMBIOS1 SKU string.

`uuid`=`<UUID>` ;;

Set SMBIOS1 UUID.

`version`=`<Base64 encoded string>` ;;

Set SMBIOS1 version.

`smp`: `<integer> (1 - N)` ('default =' `1`)::

The number of CPUs. Please use option -sockets instead.

`sockets`: `<integer> (1 - N)` ('default =' `1`)::

The number of CPU sockets.

`spice_enhancements`: `[foldersharing=<1|0>] [,videostreaming=<off|all|filter>]` ::

Configure additional enhancements for SPICE.

`foldersharing`=`<boolean>` ('default =' `0`);;

Enable folder sharing via SPICE. Needs Spice-WebDAV daemon installed in the VM.

`videostreaming`=`<all | filter | off>` ('default =' `off`);;

Enable video streaming. Uses compression for detected video streams.

`sshkeys`: `<string>` ::

cloud-init: Setup public SSH keys (one key per line, OpenSSH format).

`startdate`: `(now | YYYY-MM-DD | YYYY-MM-DDTHH:MM:SS)` ('default =' `now`)::

Set the initial date of the real time clock. Valid format for date are:'now' or '2006-06-17T16:01:21' or '2006-06-17'.

`startup`: `[[order=]\d+] [,up=\d+] [,down=\d+] ` ::

Startup and shutdown behavior. Order is a non-negative number defining the general startup order. Shutdown in done with reverse ordering. Additionally you can set the 'up' or 'down' delay in seconds, which specifies a delay to wait before the next VM is started or stopped.

`tablet`: `<boolean>` ('default =' `1`)::

Enable/disable the USB tablet device. This device is usually needed to allow absolute mouse positioning with VNC. Else the mouse runs out of sync with normal VNC clients. If you're running lots of console-only guests on one host, you may consider disabling this to save some context switches. This is turned off by default if you use spice (`qm set <vmid> --vga qxl`).

`tags`: `<string>` ::

Tags of the VM. This is only meta information.

`tdf`: `<boolean>` ('default =' `0`)::

Enable/disable time drift fix.

`template`: `<boolean>` ('default =' `0`)::

Enable/disable Template.

`tpmstate0`: `[file=]<volume> [,size=<DiskSize>] [,version=<v1.2|v2.0>]` ::

Configure a Disk for storing TPM state. The format is fixed to 'raw'.

`file`=`<volume>` ;;

The drive's backing volume.

`size`=`<DiskSize>` ;;

Disk size. This is purely informational and has no effect.

`version`=`<v1.2 | v2.0>` ('default =' `v2.0`);;

The TPM interface version. v2.0 is newer and should be preferred. Note that this cannot be changed later on.

`unused[n]`: `[file=]<volume>` ::

Reference to unused volumes. This is used internally, and should not be modified manually.

`file`=`<volume>` ;;

The drive's backing volume.

`usb[n]`: `[host=]<HOSTUSBDEVICE|spice> [,usb3=<1|0>]` ::

Configure an USB device (n is 0 to 4).

`host`=`<HOSTUSBDEVICE|spice>` ;;

The Host USB device or port or the value 'spice'. HOSTUSBDEVICE syntax is:
+
 'bus-port(.port)*' (decimal numbers) or
 'vendor_id:product_id' (hexadeciaml numbers) or
 'spice'
+
You can use the 'lsusb -t' command to list existing usb devices.
+
NOTE: This option allows direct access to host hardware. So it is no longer possible to migrate such
machines - use with special care.
+
The value 'spice' can be used to add a usb redirection devices for spice.

`usb3`=`<boolean>` ('default =' `0`);;

Specifies whether if given host option is a USB3 device or port.

`vcpus`: `<integer> (1 - N)` ('default =' `0`)::

Number of hotplugged vcpus.

`vga`: `[[type=]<enum>] [,memory=<integer>]` ::

Configure the VGA Hardware. If you want to use high resolution modes (>= 1280x1024x16) you may need to increase the vga memory option. Since QEMU 2.9 the default VGA display type is 'std' for all OS types besides some Windows versions (XP and older) which use 'cirrus'. The 'qxl' option enables the SPICE display server. For win* OS you can select how many independent displays you want, Linux guests can add displays them self.
You can also run without any graphic card, using a serial device as terminal.

`memory`=`<integer> (4 - 512)` ;;

Sets the VGA memory (in MiB). Has no effect with serial display.

`type`=`<cirrus | none | qxl | qxl2 | qxl3 | qxl4 | serial0 | serial1 | serial2 | serial3 | std | virtio | virtio-gl | vmware>` ('default =' `std`);;

Select the VGA type.

`virtio[n]`: `[file=]<volume> [,aio=<native|threads|io_uring>] [,backup=<1|0>] [,bps=<bps>] [,bps_max_length=<seconds>] [,bps_rd=<bps>] [,bps_rd_max_length=<seconds>] [,bps_wr=<bps>] [,bps_wr_max_length=<seconds>] [,cache=<enum>] [,cyls=<integer>] [,detect_zeroes=<1|0>] [,discard=<ignore|on>] [,format=<enum>] [,heads=<integer>] [,iops=<iops>] [,iops_max=<iops>] [,iops_max_length=<seconds>] [,iops_rd=<iops>] [,iops_rd_max=<iops>] [,iops_rd_max_length=<seconds>] [,iops_wr=<iops>] [,iops_wr_max=<iops>] [,iops_wr_max_length=<seconds>] [,iothread=<1|0>] [,mbps=<mbps>] [,mbps_max=<mbps>] [,mbps_rd=<mbps>] [,mbps_rd_max=<mbps>] [,mbps_wr=<mbps>] [,mbps_wr_max=<mbps>] [,media=<cdrom|disk>] [,replicate=<1|0>] [,rerror=<ignore|report|stop>] [,ro=<1|0>] [,secs=<integer>] [,serial=<serial>] [,shared=<1|0>] [,size=<DiskSize>] [,snapshot=<1|0>] [,trans=<none|lba|auto>] [,werror=<enum>]` ::

Use volume as VIRTIO hard disk (n is 0 to 15).

`aio`=`<io_uring | native | threads>` ;;

AIO type to use.

`backup`=`<boolean>` ;;

Whether the drive should be included when making backups.

`bps`=`<bps>` ;;

Maximum r/w speed in bytes per second.

`bps_max_length`=`<seconds>` ;;

Maximum length of I/O bursts in seconds.

`bps_rd`=`<bps>` ;;

Maximum read speed in bytes per second.

`bps_rd_max_length`=`<seconds>` ;;

Maximum length of read I/O bursts in seconds.

`bps_wr`=`<bps>` ;;

Maximum write speed in bytes per second.

`bps_wr_max_length`=`<seconds>` ;;

Maximum length of write I/O bursts in seconds.

`cache`=`<directsync | none | unsafe | writeback | writethrough>` ;;

The drive's cache mode

`cyls`=`<integer>` ;;

Force the drive's physical geometry to have a specific cylinder count.

`detect_zeroes`=`<boolean>` ;;

Controls whether to detect and try to optimize writes of zeroes.

`discard`=`<ignore | on>` ;;

Controls whether to pass discard/trim requests to the underlying storage.

`file`=`<volume>` ;;

The drive's backing volume.

`format`=`<cloop | cow | qcow | qcow2 | qed | raw | vmdk>` ;;

The drive's backing file's data format.

`heads`=`<integer>` ;;

Force the drive's physical geometry to have a specific head count.

`iops`=`<iops>` ;;

Maximum r/w I/O in operations per second.

`iops_max`=`<iops>` ;;

Maximum unthrottled r/w I/O pool in operations per second.

`iops_max_length`=`<seconds>` ;;

Maximum length of I/O bursts in seconds.

`iops_rd`=`<iops>` ;;

Maximum read I/O in operations per second.

`iops_rd_max`=`<iops>` ;;

Maximum unthrottled read I/O pool in operations per second.

`iops_rd_max_length`=`<seconds>` ;;

Maximum length of read I/O bursts in seconds.

`iops_wr`=`<iops>` ;;

Maximum write I/O in operations per second.

`iops_wr_max`=`<iops>` ;;

Maximum unthrottled write I/O pool in operations per second.

`iops_wr_max_length`=`<seconds>` ;;

Maximum length of write I/O bursts in seconds.

`iothread`=`<boolean>` ;;

Whether to use iothreads for this drive

`mbps`=`<mbps>` ;;

Maximum r/w speed in megabytes per second.

`mbps_max`=`<mbps>` ;;

Maximum unthrottled r/w pool in megabytes per second.

`mbps_rd`=`<mbps>` ;;

Maximum read speed in megabytes per second.

`mbps_rd_max`=`<mbps>` ;;

Maximum unthrottled read pool in megabytes per second.

`mbps_wr`=`<mbps>` ;;

Maximum write speed in megabytes per second.

`mbps_wr_max`=`<mbps>` ;;

Maximum unthrottled write pool in megabytes per second.

`media`=`<cdrom | disk>` ('default =' `disk`);;

The drive's media type.

`replicate`=`<boolean>` ('default =' `1`);;

Whether the drive should considered for replication jobs.

`rerror`=`<ignore | report | stop>` ;;

Read error action.

`ro`=`<boolean>` ;;

Whether the drive is read-only.

`secs`=`<integer>` ;;

Force the drive's physical geometry to have a specific sector count.

`serial`=`<serial>` ;;

The drive's reported serial number, url-encoded, up to 20 bytes long.

`shared`=`<boolean>` ('default =' `0`);;

Mark this locally-managed volume as available on all nodes.
+
WARNING: This option does not share the volume automatically, it assumes it is shared already!

`size`=`<DiskSize>` ;;

Disk size. This is purely informational and has no effect.

`snapshot`=`<boolean>` ;;

Controls qemu's snapshot mode feature. If activated, changes made to the disk are temporary and will be discarded when the VM is shutdown.

`trans`=`<auto | lba | none>` ;;

Force disk geometry bios translation mode.

`werror`=`<enospc | ignore | report | stop>` ;;

Write error action.

`vmgenid`: `<UUID>` ('default =' `1 (autogenerated)`)::

The VM generation ID (vmgenid) device exposes a 128-bit integer value identifier to the guest OS. This allows to notify the guest operating system when the virtual machine is executed with a different configuration (e.g. snapshot execution or creation from a template). The guest operating system notices the change, and is then able to react as appropriate by marking its copies of distributed databases as dirty, re-initializing its random number generator, etc.
Note that auto-creation only works when done through API/CLI create or update methods, but not when manually editing the config file.

`vmstatestorage`: `<string>` ::

Default storage for VM state volumes/files.

`watchdog`: `[[model=]<i6300esb|ib700>] [,action=<enum>]` ::

Create a virtual hardware watchdog device. Once enabled (by a guest action), the watchdog must be periodically polled by an agent inside the guest or else the watchdog will reset the guest (or execute the respective action specified)

`action`=`<debug | none | pause | poweroff | reset | shutdown>` ;;

The action to perform if after activation the guest fails to poll the watchdog in time.

`model`=`<i6300esb | ib700>` ('default =' `i6300esb`);;

Watchdog type to emulate.