virt-v2v(1)

名前
virt-v2v - Convert a guest to use KVM

書式
 virt-v2v [-i mode] [other -i* options]
          [-o mode] [other -o* options]
          [virt-customize options]
          [guest|filename]

説明
Virt-v2v converts a single guest from a foreign hypervisor to run on KVM. It can read Linux and Windows guests running on VMware, Xen Hyper-V and some other hypervisors, and convert them to KVM managed by libvirt, OpenStack, oVirt or several other targets. It can modify the guest to make it bootable on KVM and install virtio drivers so it will run quickly.

There is also a companion front-end called virt-p2v(1) which comes as an ISO, CD or PXE image that can be booted on physical machines to virtualize those machines (physical to virtual, or p2v).

To estimate the disk space needed before conversion, see virt-v2v-inspector(1).

For in-place conversion, there is a separate tool called virt-v2v-in-place(1).

  Input and Output
You normally run virt-v2v with several -i* options controlling the input mode and also several -o* options controlling the output mode. In this sense, "input" refers to the source foreign hypervisor such as VMware, and "output" refers to the target KVM-based management system such as oVirt or OpenStack.

The input and output sides of virt-v2v are separate and unrelated. Virt-v2v can read from any input and write to any output. Therefore these sides of virt-v2v are documented separately in this manual.

Virt-v2v normally copies from the input to the output, called "copying mode". In this case the source guest is always left unchanged. In-place conversions may be done using virt-v2v-in-place(1).

  Customization
Virt-v2v can also customize the guest during conversion, using the same options as virt-customize(1). For example, injecting files using --upload, or using --firstboot-script to add additional script(s) to run at the first boot after conversion. Read the virt-customize manual for more information on this topic.

  Other virt-v2v topics
virt-v2v-support(1) — Supported hypervisors, virtualization management systems, guests.

virt-v2v-input-vmware(1) — Input from VMware.

 L<virt-v2v-input-xen(1)> — Input from Xen.

virt-v2v-output-local(1) — Output to local files or local libvirt.

 L<virt-v2v-output-ovirt(1)> — Output to oVirt

virt-v2v-output-openstack(1) — Output to OpenStack.

virt-v2v-release-notes-1.42(1) — Release notes for 1.42 release.

virt-v2v-release-notes-2.0(1) — Release notes for 2.0 release.

virt-v2v-release-notes-2.2(1) — Release notes for 2.2 release.

virt-v2v-release-notes-2.4(1) — Release notes for 2.4 release.

virt-v2v-release-notes-2.6(1) — Release notes for 2.6 release.

virt-v2v-release-notes-2.8(1) — Release notes for 2.8 release.

virt-v2v-release-notes-2.10(1) — Release notes for 2.10 release.

virt-v2v-release-notes-2.12(1) — Release notes for 2.12 release.

例

  Convert from VMware vCenter server to local libvirt
You have a VMware vCenter server called "vcenter.example.com", a datacenter called "Datacenter", and an ESXi hypervisor called "esxi". You want to convert a guest called "vmware_guest" to run locally under libvirt.

 virt-v2v -ic vpx://vcenter.example.com/Datacenter/esxi vmware_guest

In this case you will most likely have to run virt-v2v as "root", since it needs to talk to the system libvirt daemon and copy the guest disks to /var/lib/libvirt/images.

For more information see virt-v2v-input-vmware(1).

  Convert from VMware to oVirt
This is the same as the previous example, except you want to send the guest to an oVirt Data Domain using the oVirt REST API. Guest network interface(s) are connected to the target network called "ovirtmgmt".

 virt-v2v -ic vpx://vcenter.example.com/Datacenter/esxi vmware_guest \
   -o ovirt-upload -oc https://ovirt-engine.example.com/ovirt-engine/api \
   -os ovirt-data -op /tmp/ovirt-admin-password -of raw \
   -oo ovirt-cafile=/tmp/ca.pem --bridge ovirtmgmt

In this case the host running virt-v2v acts as a conversion server.

For more information see virt-v2v-output-ovirt(1).

  Convert from ESXi hypervisor over SSH to local libvirt
You have an ESXi hypervisor called "esxi.example.com" with SSH access enabled. You want to convert from VMFS storage on that server to a local file.

 virt-v2v \
   -i vmx -it ssh \
   "ssh://root@esxi.example.com/vmfs/volumes/datastore1/guest/guest.vmx" \
   -o local -os /var/tmp

The guest must not be running.

Virt-v2v does not need to be run as root.

For more information about converting from VMX files see virt-v2v-input-vmware(1).

  Convert disk image to OpenStack
Given a disk image from another hypervisor that you want to convert to run on OpenStack (only KVM-based OpenStack is supported), you can run virt-v2v inside an OpenStack VM (called "v2v-vm" below), and do:

 virt-v2v -i disk disk.img -o openstack -oo server-id=v2v-vm

See virt-v2v-output-openstack(1).

  Convert disk image to disk image
Given a disk image from another hypervisor that you want to convert to run on KVM, you have two options. The simplest way is to try:

 virt-v2v -i disk disk.img -o local -os /var/tmp

where virt-v2v guesses everything about the input disk.img and (in this case) writes the converted result to /var/tmp.

A more complex method is to write some libvirt XML describing the input guest (if you can get the source hypervisor to provide you with libvirt XML, then so much the better). You can then do:

 virt-v2v -i libvirtxml guest-domain.xml -o local -os /var/tmp

Since guest-domain.xml contains the path(s) to the guest disk image(s) you do not need to specify the name of the disk image on the command line.

To convert a local disk image and immediately boot it in local qemu, do:

 virt-v2v -i disk disk.img -o qemu -os /var/tmp -oo qemu-boot

オプション

--help
    ヘルプを表示します。

--bandwidth bps
--bandwidth-file filename
    Some input methods are able to limit the network bandwidth they will use statically or dynamically. In the first variant this sets the bandwidth limit statically in bits per second. Formats like "10M" may be used (meaning 10 megabits per second).

    In the second variant the bandwidth is limited dynamically from the content of the file (also in bits per second, in the same formats supported by the first variant). You may use both parameters together, meaning: first limit to a static rate, then you can create the file while virt-v2v is running to adjust the rate dynamically.

    This is only supported for:

    •   input from Xen

    •   input from VMware VMX when using the SSH transport method

    •   input from VDDK

    •   -i libvirtxml when using HTTP or HTTPS disks

    •   input from VMware vCenter server

    The options are silently ignored for other input methods.

-b ...
--bridge ...
    See --network below.

--block-driver virtio-blk
--block-driver virtio-scsi
    When choosing a block driver for Windows guests, prefer "virtio-blk" or "virtio-scsi". The default is "virtio-blk".

    Note this has no effect for Linux guests at the moment. That may be added in future.

--collect GUEST[:LOCAL]
--collect-output PATH/TO/OUTPUT.tar.xz
    See "Collecting files for later diagnostics"

--colors
--colours
    Use ANSI colour sequences to colourize messages. This is the default when the output is a tty. If the output of the program is redirected to a file, ANSI colour sequences are disabled unless you use this option.

--echo-keys
    When prompting for keys and passphrases, virt-v2v normally turns echoing off so you cannot see what you are typing. If you are not worried about Tempest attacks and there is no one else in the room you can specify this flag to see what you are typing.

    Note this options only applies to keys and passphrases for encrypted devices and partitions, not for passwords used to connect to remote servers.

-i disk disk [disk ...]
    Set the input method to disk.

    In this mode you can read a virtual machine disk image with no metadata. virt-v2v tries to guess the best default metadata. This is usually adequate but you can get finer control (eg. of memory and vCPUs) by using -i libvirtxml instead.

    Each disk can be a local file or an "nbd://" URI if you want to pull the guest disk from an NBD server (see nbd_connect_uri(3) for the supported URI formats).

-i libvirt name|UUID
    Set the input method to libvirt. This is the default.

    In this mode you have to specify a libvirt guest name or UUID on the command line. You may also specify a libvirt connection URI (see -ic).

    See "Starting the libvirt system instance" below.

-i libvirtxml guest.xml
    Set the input method to libvirtxml.

    In this mode you have to pass a libvirt XML file on the command line. This file is read in order to get metadata about the source guest (such as its name, amount of memory), and also to locate the input disks. See "Minimal XML for -i libvirtxml option" below.

-i local disk [disk ...]
    This is the same as -i disk.

-i ova guest.ova
    Set the input method to ova.

    In this mode you can read a VMware ova file. Virt-v2v will read the ova manifest file and check the vmdk volumes for validity (checksums) as well as analyzing the ovf file, and then convert the guest. See virt-v2v-input-vmware(1).

-i vmx guest.vmx|ssh://...
    Set the input method to vmx.

    In this mode you can read a VMware vmx file directly or over SSH. This is useful when VMware VMs are stored on an NFS server which you can mount directly, or where you have access by SSH to an ESXi hypervisor. See virt-v2v-input-vmware(1).

-ic libvirtURI
    Specify a libvirt connection URI to use when reading the guest. This is only used when -i libvirt.

    Only local libvirt connections, or VMware vCenter connections , or RHEL 5 Xen remote connections can be used. Other remote libvirt connections will not work in general.

    See also: virt-v2v-input-vmware(1) , virt-v2v-input-xen(1)

-if format
    For -i disk only, this specifies the format of the input disk image. For other input methods you should specify the input format in the metadata.

-io OPTION=VALUE
    Set input option(s) related to the current input mode or transport. To display short help on what options are available you can use:

     virt-v2v -it vddk -io "?"

-io vddk-libdir=LIBDIR
    Set the VDDK library directory. This directory should contain subdirectories called include, lib64 etc., but do not include lib64 actually in the parameter.

    In most cases this parameter is required when using the -it vddk (VDDK) transport. See virt-v2v-input-vmware(1) for details.

-io vddk-thumbprint=xx:xx:xx:...
    Set the thumbprint of the remote VMware server.

    See "VDDK: Thumbprint" in virt-v2v-input-vmware(1) for details.

-io vddk-compression=COMPRESSION
-io vddk-config=FILENAME
-io vddk-cookie=COOKIE
-io vddk-file=FILE
-io vddk-nfchostport=PORT
-io vddk-port=PORT
-io vddk-snapshot=SNAPSHOT-MOREF
-io vddk-transports=MODE:MODE:...
    When using VDDK mode, these options are passed unmodified to the nbdkit(1) VDDK plugin. Please refer to nbdkit-vddk-plugin(1). Do not use these options unless you know what you are doing. These are all optional.

-ip filename
    Supply a file containing a password to be used when connecting to the target hypervisor. If this is omitted then the input hypervisor may ask for the password interactively. Note the file should contain the whole password, without any trailing newline, and for security the file should have mode 0600 so that others cannot read it.

-it ssh
    When using -i vmx, this enables the ssh transport. See virt-v2v-input-vmware(1).

-it vddk
    Use VMware VDDK as a transport to copy the input disks. See virt-v2v-input-vmware(1). If you use this parameter then you may need to use other -io vddk* options to specify how to connect through VDDK.

--key SELECTOR
    Specify a key for LUKS, to automatically open a LUKS device when using the inspection.

    --key NAME:key:KEY_STRING
    --key UUID:key:KEY_STRING
    --key all:key:KEY_STRING
        "NAME" is the libguestfs device name (eg. "/dev/sda1"). "UUID" is the device UUID. "all" means try the key against any encrypted device.

        Use the specified "KEY_STRING" as passphrase.

    --key NAME:file:FILENAME
    --key UUID:file:FILENAME
    --key all:file:FILENAME
        Read the passphrase from FILENAME.

    --key NAME:clevis
    --key UUID:clevis
    --key all:clevis
        Attempt passphrase-less unlocking for the device with Clevis, over the network. Please refer to "ENCRYPTED DISKS" in guestfs(3) for more information on network-bound disk encryption (NBDE).

        Note that if any such option is present on the command line, QEMU user networking will be automatically enabled for the libguestfs appliance.

--keys-from-stdin
    Read key or passphrase parameters from stdin. The default is to try to read passphrases from the user by opening /dev/tty.

    If there are multiple encrypted devices then you may need to supply multiple keys on stdin, one per line.

    Note --keys-from-stdin only applies to keys and passphrases for encrypted devices and partitions, not for passwords used to connect to remote servers.

--mac aa:bb:cc:dd:ee:ff:network:out
--mac aa:bb:cc:dd:ee:ff:bridge:out
    Map source NIC MAC address to a network or bridge.

    See "Networks and bridges" below.

--mac aa:bb:cc:dd:ee:ff:ip:ipaddr[,gw[,len[,ns,ns,...]]]
    Force a particular interface (controlled by its MAC address) to have a static IP address after boot.

    The fields in the parameter are: "ipaddr" is the IP address. "gw" is the optional gateway IP address. "len" is the optional subnet mask length (an integer). The final parameters are zero or more nameserver IP addresses.

    This option can be supplied zero or more times.

    You only need to use this option for certain broken guests such as Windows which are unable to preserve MAC to static IP address mappings automatically. You don't need to use it if Windows is using DHCP. It is currently ignored for Linux guests since they do not have this problem.

--machine-readable
--machine-readable=format
    This option is used to make the output more machine friendly when being parsed by other programs. See "Machine readable output" below.

-m MB
--memsize MB
    Change the amount of memory allocated when doing the conversion. Virt-v2v will usually choose a suitable default. Increase this if you see that the conversion step is running out of memory.

    See also "Adjusting memory available for conversion".

-n in:out
-n out
--network in:out
--network out
-b in:out
-b out
--bridge in:out
--bridge out
    Map network (or bridge) called "in" to network (or bridge) called "out". If no "in:" prefix is given, all other networks (or bridges) are mapped to "out".

    See "Networks and bridges" below.

--no-fstrim
    Do not trim the filesystem. See "Trimming" below.

-o disk
    This is the same as -o local.

-o glance
    This is a legacy option. You should probably use -o openstack instead.

    Set the output method to OpenStack Glance. In this mode the converted guest is uploaded to Glance. See virt-v2v-output-openstack(1).

-o kubevirt
    Set the output method to kubevirt. Note the way this mode works is experimental and will change in future.

    In this mode, the converted guest is written to a local directory specified by -os /dir (the directory must exist).

    By default the converted guest’s disks are written to:

     /dir/name-sda
     /dir/name-sdb
     [etc]

    and guest metadata is created in the associated YAML file:

     /dir/name.yaml

    where "name" is the guest name.

    You can override the disk paths by using -oo disk=... option(s).

-o libvirt
    Set the output method to libvirt. This is the default.

    In this mode, the converted guest is created as a libvirt guest. You may also specify a libvirt connection URI (see -oc).

    See "Starting the libvirt system instance" below, and virt-v2v-output-local(1).

-o local
    Set the output method to local.

    In this mode, the converted guest is written to a local directory specified by -os /dir (the directory must exist). The converted guest’s disks are written as:

     /dir/name-sda
     /dir/name-sdb
     [etc]

    and a libvirt XML file is created containing guest metadata:

     /dir/name.xml

    where "name" is the guest name.

-o null
    Set the output method to null.

    The guest is converted and copied but the results are thrown away and no metadata is written.

-o openstack
    Set the output method to OpenStack. See virt-v2v-output-openstack(1).

-o ovirt
    Set the output method to ovirt.

    The converted guest is written to an oVirt Export Storage Domain. The -os parameter must also be used to specify the location of the Export Storage Domain. Note this does not actually import the guest into oVirt. You have to do that manually later using the UI.

    See virt-v2v-output-ovirt(1).

-o ovirt-upload
    Set the output method to ovirt-upload.

    The converted guest is written directly to an oVirt Data Domain. This is a faster method than -o ovirt, but requires oVirt ≥ 4.2.

    See virt-v2v-output-ovirt(1).

-o qemu
    Set the output method to qemu.

    This is similar to -o local, except that a shell script is written which you can use to boot the guest in qemu. The converted disks and shell script are written to the directory specified by -os.

    When using this output mode, you can also specify the -oo qemu-boot option which boots the guest under qemu immediately.

-o vdsm
    Set the output method to vdsm.

    This mode is similar to -o ovirt, but the full path to the data domain must be given: /ovirt/data-center/<data-center-uuid>/<data-domain-uuid>. This mode is only used when virt-v2v runs under VDSM control.

-oa sparse
-oa preallocated
    Set the output file allocation mode. The default is "sparse".

-oc URI
    Specify a connection URI to use when writing the converted guest.

    For -o libvirt this is the libvirt URI. Only local libvirt connections can be used. Remote libvirt connections will not work. See virt-v2v-output-local(1) for further information.

-of format
    When converting the guest, convert the disks to the given format.

    If not specified, then the input format is used.

-on name
    Rename the guest when converting it. If this option is not used then the output name is the same as the input name.

-oo OPTION=VALUE
    Set output option(s) related to the current output mode. To display short help on what options are available you can use:

     $ virt-v2v -o libvirt -oo "?"
     Output options that can be used with -o libvirt:

      -oo compressed      Compress the output file (used only with
                          -of qcow2)

-oo compressed
    For outputs which support qcow2 format (-of qcow2), this writes a compressed qcow2 file. It is the equivalent to the -c option of qemu-img(1).

-oo create=false
    For -o kubevirt, indicate that another management process will create the output disks, so do not (re-)create them in virt-v2v.

-oo disk=DISK
    For -o kubevirt this overrides the path to each output disk, instead of using the default which is "DISK-sda" etc in the output storage (-os) path. If you use this option at all, you must repeat it once for each guest disk. If you don't use it, then the default method of putting disks in the output storage path is used.

-oo guest-id="ID"
    For -o openstack (virt-v2v-output-openstack(1)) only, set a guest ID which is saved on each Cinder volume in the "virt_v2v_guest_id" volume property.

-oo qemu-boot
    When using -o qemu only, this boots the guest immediately after virt-v2v finishes.

-oo os-*=*
    For -o openstack (virt-v2v-output-openstack(1)) only, set optional OpenStack authentication. For example -oo os-username=NAME is equivalent to "openstack --os-username=NAME".

-oo ovirt-cafile=ca.pem
    For -o ovirt-upload (virt-v2v-output-ovirt(1)) only, the ca.pem file (Certificate Authority), copied from /etc/pki/ovirt-engine/ca.pem on the oVirt engine.

-oo ovirt-cluster="CLUSTERNAME"
    For -o ovirt-upload (virt-v2v-output-ovirt(1)) only, set the oVirt Cluster Name. If not given it uses "Default".

-oo ovirt-proxy
    For -o ovirt-upload (virt-v2v-output-ovirt(1)) only, proxy the upload through oVirt Engine. This is slower than uploading directly to the oVirt node but may be necessary if you do not have direct network access to the nodes.

-oo ovirt-verifypeer
    For -o ovirt-upload (virt-v2v-output-ovirt(1)) only, verify the oVirt server’s identity by checking the server‘s certificate against the Certificate Authority.

-oo server-id="NAME|UUID"
    For -o openstack (virt-v2v-output-openstack(1)) only, set the name of the conversion appliance where virt-v2v is running.

-oo vdsm-compat=0.10
-oo vdsm-compat=1.1
    If -o vdsm and the output format is qcow2, then we add the qcow2 compat=0.10 option to the output file for compatibility with RHEL 6 (see https://bugzilla.redhat.com/1145582).

    If -oo vdsm-compat=1.1 is used then modern qcow2 (compat=1.1) files are generated instead.

    Currently -oo vdsm-compat=0.10 is the default, but this will change to -oo vdsm-compat=1.1 in a future version of virt-v2v (when we can assume that everyone is using a modern version of qemu).

    Note this option only affects -o vdsm output. All other output modes (including -o ovirt) generate modern qcow2 compat=1.1 files, always.

    If this option is available, then "vdsm-compat-option" will appear in the --machine-readable output.

-oo vdsm-image-uuid=UUID
-oo vdsm-vol-uuid=UUID
-oo vdsm-vm-uuid=UUID
-oo vdsm-ovf-output=DIR
    Normally the oVirt output mode chooses random UUIDs for the target guest. However VDSM needs to control the UUIDs and passes these parameters when virt-v2v runs under VDSM control. The parameters control:

    •   the image directory of each guest disk (-oo vdsm-image-uuid) (this option is passed once for each guest disk)

    •   UUIDs for each guest disk (-oo vdsm-vol-uuid) (this option is passed once for each guest disk)

    •   the OVF file name (-oo vdsm-vm-uuid).

    •   the OVF output directory (default current directory) (-oo vdsm-ovf-output).

    The format of UUIDs is: "12345678-1234-1234-1234-123456789abc" (each hex digit can be "0-9" or "a-f"), conforming to OSF DCE 1.1.

    These options can only be used with -o vdsm.

-oo vdsm-ovf-flavour=flavour
    This option controls the format of the OVF generated at the end of conversion. Currently there are two possible flavours:

    ovirtexp
        The OVF format used in oVirt export storage domain.

    ovirt
        The OVF format understood by oVirt REST API.

    For backward compatibility the default is ovirtexp, but this may change in the future.

-oo verify-server-certificate
-oo verify-server-certificate="true|false"
    For -o openstack (virt-v2v-output-openstack(1)) only, this can be used to disable SSL certification validation when connecting to OpenStack by specifying -oo verify-server-certificate=false.

-op file
    Supply a file containing a password to be used when connecting to the target hypervisor. Note the file should contain the whole password, without any trailing newline, and for security the file should have mode 0600 so that others cannot read it.

-os storage
    The location of the storage for the converted guest.

    For -o libvirt, this is a libvirt directory pool (see "virsh pool-list") or pool UUID.

    For -o local and -o qemu, this is a directory name. The directory must exist.

    For -o openstack, this is the optional Cinder volume type.

     For I<-o ovirt-upload>, this is the name of the destination Storage Domain.

    For -o ovirt, this can be an NFS path of the Export Storage Domain of the form "<host>:<path>", eg:

     ovirt-storage.example.com:/ovirt/export

    The NFS export must be mountable and writable by the user and host running virt-v2v, since the virt-v2v program has to actually mount it when it runs. So you probably have to run virt-v2v as "root".

    Or: You can mount the Export Storage Domain yourself, and point -os to the mountpoint. Note that virt-v2v will still need to write to this remote directory, so virt-v2v will still need to run as "root".

    You will get an error if virt-v2v is unable to mount/write to the Export Storage Domain.

--parallel N
    Enable parallel copying if the guest has multiple disks. N is the maximum number of parallel nbdcopy(1) instances to run.

    The default is to run at most one instance of nbdcopy (ie. --parallel=1). All versions of virt-v2v ≤ 2.7.2 also did disk copies one at a time.

    Within each guest disk, nbdcopy tries to copy in parallel if the underlying endpoints support that. This is not affected by this command line option. See the nbdcopy(1) manual page for details.

--print-source
    Print information about the source guest and stop. This option is useful when you are setting up network and bridge maps. See "Networks and bridges".

-q
--quiet
    This disables progress bars and other unnecessary output.

--root ask
--root single
    Choose the root filesystem to be converted.

    In the case where the virtual machine is dual-boot or multi-boot, or where the VM has other filesystems that look like operating systems, this option can be used to select the root filesystem (a.k.a. "C:" drive or /) of the operating system that is to be converted. The Windows Recovery Console, certain attached DVD drives, and bugs in libguestfs inspection heuristics, can make a guest look like a multi-boot operating system.

    Either virt-inspector(1) or virt-v2v-open(1) can be used to list the roots for a dual-boot or multi-boot VM.

    The default in virt-v2v ≤ 0.7.1 was --root single, which causes virt-v2v to die if a multi-boot operating system is found.

    Since virt-v2v ≥ 0.7.2 the default is now --root ask: If the VM is found to be multi-boot, then virt-v2v will stop and list the possible root filesystems and ask the user which to use. This requires that virt-v2v is run interactively.

--root first
    Choose the first root device in the case of a multi-boot operating system. Since this is a heuristic, it may sometimes choose the wrong one, and it may not choose the default option from the guest bootloader. For predictable results it is better to use virt-v2v-open(1) and virt-inspector(1) to inspect the guest and then specify which root you want to convert.

--root /dev/sdX
--root /dev/VG/LV
    Name a specific root device to convert, eg. --root /dev/sda2 would mean to use the second partition on the first hard drive. If the named root device does not exist or was not detected as a root device, then virt-v2v will fail.

--smp N
    Change the number of virtual CPUs used when doing the conversion. Virt-v2v will usually choose a suitable default.

    Increasing this beyond 8 may improve conversion performance, if your host has sufficient physical CPUs. You may also need to increase the memory size (--memsize option).

-v
--verbose
    デバッグ用の冗長なメッセージを有効にします。

-V
--version
    バージョン番号を表示して、終了します。

--wrap
    Wrap error, warning, and informative messages. This is the default when the output is a tty. If the output of the program is redirected to a file, wrapping is disabled unless you use this option.

-x  libguestfs API 呼び出しのトレースを有効にします。

  Customization options
__CUSTOMIZE_OPTIONS__

RESOURCE REQUIREMENTS

  Network
The most important resource for virt-v2v appears to be network bandwidth. Virt-v2v should be able to copy guest data at gigabit ethernet speeds or greater.

Ensure that the network connections between servers (conversion server, NFS server, vCenter, etc.) are as fast and as low latency as possible.

  Disk space
Virt-v2v places potentially large temporary files in $VIRT_V2V_TMPDIR (usually /var/tmp, see also "ENVIRONMENT VARIABLES" below). Using tmpfs is a bad idea.

For each guest disk, an overlay is stored temporarily. This stores the changes made during conversion, and is used as a cache. The overlays are not particularly large - tens or low hundreds of megabytes per disk is typical. In addition to the overlay(s), input and output methods may use disk space, as outlined in the table below.

-i ova
    This temporarily places a full copy of the uncompressed source disks in $VIRT_V2V_TMPDIR (or /var/tmp).

-o glance
    This temporarily places a full copy of the output disks in $VIRT_V2V_TMPDIR (or /var/tmp).

-o local
-o qemu
    You must ensure there is sufficient space in the output directory for the converted guest.

See also "Minimum free space check in the host" below.

  VMware vCenter resources
Copying from VMware vCenter is currently quite slow, but we believe this to be an issue with VMware. Ensuring the VMware ESXi hypervisor and vCenter are running on fast hardware with plenty of memory should alleviate this.

  Compute power and RAM
Virt-v2v can be run in a virtual machine, but may run faster on bare metal.

Virt-v2v is not especially compute or RAM intensive. If you are running many parallel conversions, then you may consider allocating one CPU core and 2 GB of RAM per running instance. (You may adjust the amount of memory used by conversion, see the next heading.)

  Adjusting memory available for conversion
Virt-v2v --memsize=N can be used to increase the amount of memory available to do conversion. This rarely needs to be adjusted, but can help to workaround some conversion problems.

Linux: setfiles runs out of memory when relabelling

For Linux guests that use SELinux, setfiles can run out of memory if a single directory contains millions of files. As there is no simple way for virt-v2v to detect this problem in advance, you may have to use --memsize=4000 (or larger) to convert such guests. For details see https://issues.redhat.com/browse/RHEL-125116

  Trimming
Virt-v2v attempts to optimize the speed of conversion by ignoring guest filesystem data which is not used. This would include unused filesystem blocks, blocks containing zeroes, and deleted files.

To do this, virt-v2v issues a non-destructive fstrim(8) operation. As this happens to an overlay placed over the guest data, it does not affect the source in any way.

If this fstrim operation fails, you will see a warning, but virt-v2v will continue anyway. It may run more slowly (in some cases much more slowly), because it is copying the unused parts of the disk.

Unfortunately support for fstrim is not universal, and it also depends on specific details of the filesystem, partition alignment, and backing storage. As an example, NTFS filesystems cannot be fstrimmed if they occupy a partition which is not aligned to the underlying storage. That was the default on Windows before Vista. As another example, VFAT filesystems (used by UEFI guests) cannot be trimmed at all.

fstrim support in the Linux kernel is improving gradually, so over time some of these restrictions will be lifted and virt-v2v will work faster.

Use --no-fstrim to disable trimming.

  Free space for conversion
Free space in the guest

Virt-v2v checks there is sufficient free space in the guest filesystem to perform the conversion. Currently it checks:

Linux root filesystem
    Minimum free space: 100 MB

Linux /boot
    Minimum free space: 50 MB

    This is because we need to build a new initramfs for some Enterprise Linux conversions.

Windows "C:" drive
    Minimum free space: 100 MB

    We may have to copy in many virtio drivers and guest agents.

Any other mountable filesystem
    Minimum free space: 10 MB

In addition to the actual free space, each filesystem is required to have at least 100 available inodes.

Minimum free space check in the host

You must have sufficient free space in the host directory used to store large temporary overlays. To find out which directory this is, use:

 $ df -h "$(guestfish get-cachedir)"
 Filesystem        Size  Used Avail Use% Mounted on
 /dev/mapper/root   50G   40G  6.8G  86% /

and look under the "Avail" column. Virt-v2v will refuse to do the conversion at all unless at least 1GB is available there. You can change the directory that virt-v2v uses by setting $VIRT_V2V_TMPDIR.

  Running virt-v2v as root or non-root
Nothing in virt-v2v inherently needs root access, and it will run just fine as a non-root user. However, certain external features may require either root or a special user:

Mounting the Export Storage Domain
    When using -o ovirt -os server:/esd virt-v2v has to have sufficient privileges to NFS mount the Export Storage Domain from "server".

    You can avoid needing root here by mounting it yourself before running virt-v2v, and passing -os /mountpoint instead, but first of all read the next section ...

Writing to the Export Storage Domain as 36:36
    oVirt cannot read files and directories from the Export Storage Domain unless they have UID:GID 36:36. You will see VM import problems if the UID:GID is not correct.

    When you run virt-v2v -o ovirt as root, virt-v2v attempts to create files and directories with the correct ownership. If you run virt-v2v as non-root, it will probably still work, but you will need to manually change ownership after virt-v2v has finished.

Writing to libvirt
    When using -o libvirt, you may need to run virt-v2v as root so that it can write to the libvirt system instance (ie. "qemu:///system") and to the default location for disk images (usually /var/lib/libvirt/images).

    You can avoid this by setting up libvirt connection authentication, see http://libvirt.org/auth.html. Alternatively, use -oc qemu:///session, which will write to your per-user libvirt instance.

    See also "Starting the libvirt system instance".

Writing to Openstack
    Because of how Cinder volumes are presented as /dev block devices, using -o openstack normally requires that virt-v2v is run as root.

Writing to Glance
    This does not need root (in fact it probably won’t work), but may require either a special user and/or for you to source a script that sets authentication environment variables. Consult the Glance documentation.

Writing to block devices
    This normally requires root. See the next section.

  Writing to block devices
Some output modes write to local files. In general these modes also let you write to block devices, but before you run virt-v2v you may have to arrange for symbolic links to the desired block devices in the output directory.

For example if using -o local -os /dir then virt-v2v would normally create files called:

 /dir/name-sda     # first disk
 /dir/name-sdb     # second disk
 ...
 /dir/name.xml     # metadata

If you wish the disks to be written to block devices then you would need to create /dir/name-sda (etc) as symlinks to the block devices:

 # lvcreate -L 10G -n VolumeForDiskA VG
 # lvcreate -L 6G -n VolumeForDiskB VG
 # ln -sf /dev/VG/VolumeForDiskA /dir/name-sda
 # ln -sf /dev/VG/VolumeForDiskB /dir/name-sdb

Note that you must precreate the correct number of block devices of the correct size. Typically -of raw has to be used too, but other formats such as qcow2 can be useful occasionally so virt-v2v does not force you to use raw on block devices.

PRE-CONVERSION TASKS

  Remove Anti-Virus (AV) and Group Policy (GPO)
Anti-Virus software and Windows Group Policy is designed to prevent the kind of driver installation and other changes that we may make to Windows guests. It is recommended that you disable or remove this before conversion. It may be enabled again after conversion.

  Relax Windows PowerShell ExecutionPolicy
Virt-v2v runs unsigned firstboot PowerShell scripts. Certain Windows PowerShell "ExecutionPolicy" settings such as "AllSigned" may cause the scripts to fail to run.

To find the current policy use the Get-ExecutionPolicy command:

 Get-ExecutionPolicy -List

To relax the policy use Set-ExecutionPolicy. You can set the policy back after conversion.

See also: https:/go.microsoft.com/fwlink/?LinkID=135170 https://redhat.atlassian.net/browse/MTV-4424

  The guest should not be running
The guest must be cleanly shut down before conversion begins, and must not be restarted on the source except if conversion fails. If the guest is running or starts running during conversion then you will end up with filesystem corruption in the converted guest.

Virt-v2v tries to ensure the guest is shut down before conversion when it can, but sometimes that is not possible. It is also not possible to prevent a guest from being started while conversion is going on, or after a successful conversion. That must be done by some higher layer management tool instead.

It is possible to convert from a snapshot, but this should only be done to test if a conversion would succeed (with the result being thrown away), and you should fully understand what you are doing.

POST-CONVERSION TASKS

  Guest network configuration
Virt-v2v cannot currently reconfigure a guest’s network configuration. If the converted guest is not connected to the same subnet as the source, its network configuration may have to be updated. See also virt-customize(1).

  Converting a Windows guest
When converting a Windows guests, the conversion process is split into two stages:

1.  Offline conversion.

2.  First boot.

The guest will be bootable after the offline conversion stage, but will not yet have all necessary drivers installed to work correctly. These will be installed automatically the first time the guest boots.

N.B. Windows may reboot 4 or more times the first time after conversion. This is required to install the required drivers, guest agents, remove VMware Tools, and configure the network. Take care not to interrupt the automatic driver installation process when logging in to the guest for the first time, as this may prevent the guest from subsequently booting correctly.

  Removing VMware Tools from Windows guests
Virt-v2v attempts to remove VMware Tools. For Windows guests this is supposed to happen during the first boot after conversion.

We use VMware's recommended uninstallation method as that is the safest choice. Unfortunately this method is known not to work in most cases (it makes the assumption that it is running on top of VMware, and fails with error 1603). So VMware Tools must be manually removed by some other method.

VMware's officially documented method for manually removing VMware Tools is here: https://knowledge.broadcom.com/external/article/315629/clean-uninstallation-of-vmware-tools-in.html

Another, unofficial method is described here: https://gist.github.com/broestls/f872872a00acee2fca02017160840624 You should carefully check this script since it makes very invasive changes to the Windows Registry and filesystem.

注記

  Xen paravirtualized guests
Older versions of virt-v2v could turn a Xen paravirtualized (PV) guest into a KVM guest by installing a new kernel. This version of virt-v2v does not attempt to install any new kernels. Instead it will give you an error if there are only Xen PV kernels available.

Therefore before conversion you should check that a regular kernel is installed. For some older Linux distributions, this means installing a kernel from the table below:

 RHEL 4         i686 with > 10GB of RAM: install "kernel-hugemem"
                i686 SMP: install "kernel-smp"
                other i686: install "kernel"
                x86-64 SMP with > 8 CPUs: install "kernel-largesmp"
                x86-64 SMP: install "kernel-smp"
                other x86-64: install "kernel"

 RHEL 5         i686: install "kernel-PAE"
                x86-64: install "kernel"

 SLES 10        i586 with > 10GB of RAM: install "kernel-bigsmp"
                i586 SMP: install "kernel-smp"
                other i586: install "kernel-default"
                x86-64 SMP: install "kernel-smp"
                other x86-64: install "kernel-default"

 SLES 11+       i586: install "kernel-pae"
                x86-64: install "kernel-default"

 Windows        (Does not apply, as there is no Xen PV Windows kernel)

  Enabling virtio
"Virtio" is the name for a set of drivers which make disk (block device), network and other guest operations work much faster on KVM.

Older versions of virt-v2v could install these drivers for certain Linux guests. This version of virt-v2v does not attempt to install new Linux kernels or drivers, but will warn you if they are not installed already.

In order to enable virtio, and hence improve performance of the guest after conversion, you should ensure that the minimum versions of packages are installed before conversion, by consulting the table below.

 RHEL 4         kernel >= 2.5.9-89.EL
                lvm2 >= 2.02.42-5.el4
                device-mapper >= 1.02.28-2.el4
                selinux-policy-targeted >= 1.17.30-2.152.el4
                policycoreutils >= 1.18.1-4.13

 RHEL 5         kernel >= 2.6.18-128.el5
                lvm2 >= 2.02.40-6.el5
                selinux-policy-targeted >= 2.4.6-203.el5

 RHEL 6+        All versions support virtio

 Fedora         All versions support virtio

 SLES 11+       All versions support virtio

 SLES 10        kernel >= 2.6.16.60-0.85.1

 OpenSUSE 11+   All versions support virtio

 OpenSUSE 10    kernel >= 2.6.25.5-1.1

 Debian 6+      All versions support virtio

 Ubuntu 10.04+  All versions support virtio

 Windows        Drivers are installed from the ISO or directory pointed
                to by the "VIRTIO_WIN" environment variable if present.
                If the "VIRTIO_WIN" environment variable is absent
                (which is the recommended setting), then drivers are
                searched for in /usr/share/virtio-win, as installed
                by the virtio-win RPM.

  RHEL 4: SELinux relabel appears to hang forever
In RHEL ≤ 4.7 there was a bug which causes SELinux relabelling to appear to hang forever at:

 *** Warning -- SELinux relabel is required. ***
 *** Disabling security enforcement.         ***
 *** Relabeling could take a very long time, ***
 *** depending on file system size.          ***

In reality it is waiting for you to press a key (but there is no visual indication of this). You can either hit the "[Return]" key, at which point the guest will finish relabelling and reboot, or you can install policycoreutils ≥ 1.18.1-4.13 before starting the v2v conversion. See also https://bugzilla.redhat.com/show_bug.cgi?id=244636

  RHEL 8: dracut network-legacy error
In RHEL 8, a conversion fails with:

 dracut: dracut module 'network-legacy' cannot be found or installed

This is caused by an issue with a dracut update during the RHEL 8 lifecycle. You can fix it by either installing the "dhclient" package, or by removing the file /etc/dracut.conf.d/50-network-legacy.conf. Either operation should be done inside the guest before conversion. For more information, see:

https://access.redhat.com/articles/7112814

  Linux: "rename: /sysroot/etc/resolv.conf" failure
(This issue is fixed in libguestfs ≥ 1.60, the following documentation is for historical versions.)

In a Linux guest, you see an error such as this:

 virt-v2v: error: libguestfs error: command lines: rename: /sysroot/etc/resolv.conf to /sysroot/etc/lwdhuh36: Operation not permitted

This can be caused because the file /etc/resolv.conf in the guest has the immutable bit set. You can use the chattr(1) command before converting the guest:

 chattr -i /etc/resolv.conf

and then restore it (+i) after conversion.

  Debian/Ubuntu: "warning: could not determine a way to update the configuration of Grub2"
Currently, virt-v2v has no way to set the default kernel in Debian and Ubuntu guests using GRUB 2 as bootloader. This means that virt-v2v will not change the default kernel used for booting, even in case it is not the best kernel available on the guest. A recommended procedure is, before using virt-v2v, to check that the boot kernel is the best kernel available in the guest (for example by making sure the guest is up-to-date).

  Debian: "vsyscall attempted with vsyscall=none"
When run on a recent Debian host virt-v2v may fail to convert guests which were created before 2013. In the debugging output you will see a crash message similar to:

 vsyscall attempted with vsyscall=none ip:...
 segfault at ...

This is caused because Debian removed support for running old binaries which used the legacy vsyscall page to call into the kernel.

You can work around this problem by running this command before running virt-v2v:

 export LIBGUESTFS_APPEND="vsyscall=emulate"

For more information, see https://bugzilla.redhat.com/1592061

  Windows: System disk on a Dynamic Disk is not supported
If the Windows system disk (the drive containing "\windows") is located on a Dynamic Disk then it cannot be converted. Data disks — that is, disks which are part of the guest but do not contain parts of the Windows operating system — may be Dynamic Disks.

See https://bugzilla.redhat.com/2140548.

  Windows ≥ 8 Fast Startup is incompatible with virt-v2v
Guests which use the Windows ≥ 8 "Fast Startup" feature (or guests which are hibernated) cannot be converted with virt-v2v. You will see an error:

 virt-v2v: error: unable to mount the disk image for writing. This has
 probably happened because Windows Hibernation or Fast Restart is being
 used in this guest. You have to disable this (in the guest) in order
 to use virt-v2v.

As the message says, you need to boot the guest and disable the "Fast Startup" feature (Control Panel → Power Options → Choose what the power buttons do → Change settings that are currently unavailable → Turn on fast startup), and shut down the guest, and then you will be able to convert it.

For more information, see: "WINDOWS HIBERNATION AND WINDOWS 8 FAST STARTUP" in guestfs(3).

  Windows: Boot failure: 0x0000007B
This boot failure is caused by Windows being unable to find or load the right disk driver (eg. viostor.sys). If you experience this error, here are some things to check:

•   First ensure that the guest boots on the source hypervisor before conversion.

•   Check you have the Windows virtio drivers available in /usr/share/virtio-win, and that virt-v2v did not print any warning about not being able to install virtio drivers.

    On Red Hat Enterprise Linux 7, you will need to install the signed drivers available in the "virtio-win" package. If you do not have access to the signed drivers, then you will probably need to disable driver signing in the boot menus.

•   Check that you are presenting a virtio-blk interface (not virtio-scsi and not ide) to the guest. On the qemu/KVM command line you should see something similar to this:

     ... -drive file=windows-sda,if=virtio ...

    In libvirt XML, you should see:

     <target dev='vda' bus='virtio'/>

•   Check that Windows Group Policy does not prevent the driver from being installed or used. Try deleting Windows Group Policy before conversion.

•   Check there is no anti-virus or other software which implements Group Policy-like prohibitions on installing or using new drivers.

•   Enable boot debugging and check the viostor.sys driver is being loaded.

  OpenStack and Windows reactivation
OpenStack does not offer stable device / PCI addresses to guests. Every time it creates or starts a guest, it regenerates the libvirt XML for that guest from scratch. The libvirt XML will have no <address> fields. Libvirt will then assign addresses to devices, in a predictable manner. Addresses may change if any of the following are true:

•   A new disk or network device has been added or removed from the guest.

•   The version of OpenStack or (possibly) libvirt has changed.

Because Windows does not like "hardware" changes of this kind, it may trigger Windows reactivation.

This can also prevent booting with a 7B error [see previous section] if the guest has group policy containing "Device Installation Restrictions".

  Support for SHA-2 certificates in Windows 7 and Windows Server 2008 R2
Later versions of the Windows virtio drivers are signed using SHA-2 certificates (instead of SHA-1). The original shipping Windows 7 and Windows Server 2008 R2 did not understand SHA-2 certificates and so the Windows virtio drivers will not install properly.

To fix this you must apply SHA-2 Code Signing Support from: https://docs.microsoft.com/en-us/security-updates/SecurityAdvisories/2015/3033929 before converting the guest.

For further information see: https://bugzilla.redhat.com/show_bug.cgi?id=1624878

  After conversion, Windows guest cannot be upgraded
After successful conversion, the Windows guest cannot be upgraded to a later release of Windows (eg. from Windows Server 2016 to 2019).

Another symptom is that the "pnputil /enum-drivers" command cannot list all drivers. A few drivers are shown and then the command crashes with the error:

 Failed to enumerate driver packages: The parameter is incorrect.

This is caused by the "guestor_tmp" temporary driver that we preinstall during conversion so that Windows can see the boot device. Because only minimal changes are made to the Registry to make this work, Windows later gets confused when it sees these partial Registry entries.

The fix is to delete the Registry entries, after conversion but before trying to upgrade Windows. This can be achieved using virt-win-reg(1).

The Windows guest should be shut down.

The following ".reg" file should be merged into the Windows Registry: https://github.com/libguestfs/virt-v2v/blob/master/contrib/remove-guestor.reg

 # virt-win-reg --merge WindowsGuest remove-guestor.reg

Then the Windows guest can be booted and used / upgraded as normal.

Alternatively, a WinPE environment can be used to remove the Registry entries.

For further information see: https://issues.redhat.com/browse/MTV-2256

  Windows: "Activation of partially decrypted BITLK device is not supported"
This error from cryptsetup(8) may occur for Windows 11 guests that have a virtual TPM. Even if Bitlocker is not activated, the disk is still encrypted, and so a --key parameter is still required. However it may not be possible to retrieve the key from the TPM.

A workaround is to turn on Bitlocker in the Bitlocker Drive Encryption settings in the Control Panel. The Bitlocker key must be passed to virt-v2v on the command line.

For further information see: https://issues.redhat.com/browse/RHEL-70840 and https://windowstechpro.com/how-to-enable-bitlocker-on-windows-11/

  Windows: "Enter the recovery key for this drive"
After conversion, you may be presented with a Windows boot screen showing:

 BitLocker recovery
 Enter the recovery key for this drive
 [|___________________]

(See screenshot on https://issues.redhat.com/browse/RHEL-103915)

This happens when the Windows BitLocker disk encryption key is contained in the VMware Virtual Trusted Platform Module (vTPM). The vTPM is working exactly as designed. It is preventing the encrypted disk from being moved from one machine to another by storing the encryption key in trusted storage on the source. By design, we cannot access or move this key to the target.

To start the VM you will need to enter the BitLocker recovery key. This will also register the disk against the new vTPM on the target, so it should only be necessary to do this once.

For help finding the recovery key: https://aka.ms/recoverykeyfaq

  Linux: Guests with LUKS encryption and TPM fail to boot after conversion
Linux guests (such as Ubuntu) that use LUKS-encrypted disks with keys sealed to a Trusted Platform Module (TPM) will fail to boot after virt-v2v conversion. This is because the TPM is working exactly as designed: it prevents the encrypted disk from being used on a different machine. After conversion, the guest runs on a new KVM host with a different vTPM, so the TPM-sealed key is no longer valid.

To convert such a guest, a passphrase-based LUKS keyslot must exist so that virt-v2v can unlock the disk using the --key option. If the guest only has a TPM-sealed key, you must add a passphrase keyslot before conversion. Do not remove the TPM binding on the source VM as it must remain bootable in case the conversion fails.

The following commands should be run inside the source guest while it is still running on the source hypervisor (where the TPM is valid). In these examples "/dev/sda3" is the LUKS partition; substitute the appropriate device for your guest.

If the guest uses clevis for TPM2 binding (e.g. Ubuntu 22.04), first recover the sealed passphrase, then add a new keyslot:

 clevis luks list -d /dev/sda3
 clevis luks pass -d /dev/sda3 -s SLOT > /tmp/recovered-key
 cryptsetup luksAddKey /dev/sda3 --key-file /tmp/recovered-key

If the guest uses systemd-cryptenroll (e.g. Ubuntu 24.04+), "systemd-cryptenroll" does not expose the sealed passphrase, so you must supply the original installation passphrase when adding a new keyslot:

 cryptsetup luksDump /dev/sda3    # verify tpm2 token is present
 cryptsetup luksAddKey /dev/sda3

Then convert with virt-v2v, passing the passphrase you enrolled above:

 virt-v2v [...] --key all:key:PASSPHRASE

After conversion, the old TPM binding will no longer be valid. Boot the converted guest and remove the stale binding:

 clevis luks unbind -d /dev/sda3 -s SLOT -f       # clevis
 systemd-cryptenroll --wipe-slot=tpm2 /dev/sda3   # systemd-cryptenroll

If you want to re-seal LUKS against the new KVM vTPM, you can then run "clevis luks bind -d /dev/sda3 tpm2 '{}'" or "systemd-cryptenroll --tpm2-device=auto /dev/sda3" inside the converted guest.

For further information see: https://issues.redhat.com/browse/RHEL-85154

  Networks and bridges
Guests are usually connected to one or more networks, and when converted to the target hypervisor you usually want to reconnect those networks at the destination. The options --network, --bridge and --mac allow you to do that.

If you are unsure of what networks and bridges are in use on the source hypervisor, then you can examine the source metadata (libvirt XML, vCenter information, etc.). Or you can run virt-v2v with the --print-source option which causes virt-v2v to print out the information it has about the guest on the source and then exit.

In the --print-source output you will see a section showing the guest’s Network Interface Cards (NICs):

 $ virt-v2v [-i ...] --print-source name
 [...]
 NICs:
     Network "default" mac: 52:54:00:d0:cf:0e

Bridges are special classes of network devices which are attached to a named external network on the source hypervisor, for example:

 $ virt-v2v [-i ...] --print-source name
 [...]
 NICs:
     Bridge "br0"

To map a specific source bridge to a target network, for example "br0" on the source to "ovirtmgmt" on the target, use:

 virt-v2v [...] --bridge br0:ovirtmgmt

To map every bridge to a target network, use:

 virt-v2v [...] --bridge ovirtmgmt

Fine-grained mapping of guest NICs

The --mac option gives you more control over the mapping, letting you map single NICs to either networks or bridges on the target. For example a source guest with two NICs could map them individually to two networks called "mgmt" and "clientdata" like this:

 $ virt-v2v [...] \
    --mac 52:54:00:d0:cf:0e:network:mgmt \
    --mac 52:54:00:d0:cf:0f:network:clientdata

Note that virt-v2v does not have the ability to change a guest’s MAC address. The MAC address is part of the guest metadata and must remain the same on source and target hypervisors. Most guests will use the MAC address to set up persistent associations between NICs and internal names (like "eth0"), with firewall settings, or even for other purposes like software licensing.

  Collecting files for later diagnostics
The virt-v2v --collect and --collect-output options are used to collect files and directories from inside the guest, before conversion, for later diagnosis in case the conversion goes wrong, especially if driver installation at firstboot fails.

Typical usage is:

 virt-v2v [...] \
     --collect /windows/system32/config/ \
     --collect /windows/system32/winevt/logs/ \
     --collect /etc/ \
     --collect-output output.tar.xz

which would save the Windows registry, Windows event logs, and Linux /etc directory to output.tar.xz.

Guest files/directories which do not exist are ignored. The information collected may include sensitive data like passwords. The output could be arbitrarily large since it copies everything specified from the guest.

You can rename directories in the output tarball by adding ":dir" suffix to the --collect option, eg:

 virt-v2v [...] \
     --collect /windows/system32/config/:registry

which would create a registry/ directory in the tarball.

  Minimal XML for -i libvirtxml option
When using the -i libvirtxml option, you have to supply some libvirt XML. Writing this from scratch is hard, so the template below is helpful.

Note this should only be used for testing and/or where you know what you're doing! If you have libvirt metadata for the guest, always use that instead.

 <domain type='kvm'>
   <name> NAME </name>
   <memory>1048576</memory>
   <vcpu>2</vcpu>
   <os>
     <type>hvm</type>
     <boot dev='hd'/>
   </os>
   <features>
     <acpi/>
     <apic/>
     <pae/>
   </features>
   <devices>
     <disk type='file' device='disk'>
       <driver name='qemu' type='raw'/>
       <source file='/path/to/disk/image'/>
       <target dev='hda' bus='ide'/>
       <checksum method='sha256' fail='error'>123123...</checksum>
     </disk>
     <interface type='network'>
       <mac address='52:54:00:01:02:03'/>
       <source network='default'/>
       <model type='rtl8139'/>
     </interface>
   </devices>
 </domain>

  Machine readable output
The --machine-readable option can be used to make the output more machine friendly, which is useful when calling virt-v2v from other programs, GUIs etc.

このオプションを使用するには 2 通りの方法があります。

Firstly use the option on its own to query the capabilities of the virt-v2v binary. Typical output looks like this:

 $ virt-v2v --machine-readable
 virt-v2v
 libguestfs-rewrite
 colours-option
 input:disk
 [...]
 output:local
 [...]
 convert:linux
 convert:windows

A list of features is printed, one per line, and the program exits with status 0.

The "input:" and "output:" features refer to -i and -o (input and output mode) options supported by this binary. The "convert:" features refer to guest types that this binary knows how to convert.

Secondly use the option in conjunction with other options to make the regular program output more machine friendly.

At the moment this means:

1.  Progress bar messages can be parsed from stdout by looking for this regular expression:

     ^[0-9]+/[0-9]+$

2.  The calling program should treat messages sent to stdout (except for progress bar messages) as status messages. They can be logged and/or displayed to the user.

3.  The calling program should treat messages sent to stderr as error messages. In addition, virt-v2v exits with a non-zero status code if there was a fatal error.

Virt-v2v ≤ 0.9.1 did not support the --machine-readable option at all. The option was added when virt-v2v was rewritten in 2014.

It is possible to specify a format string for controlling the output; see "ADVANCED MACHINE READABLE OUTPUT" in guestfs(3).

  Starting the libvirt system instance
 Failed to connect socket to '/var/run/libvirt/virtqemud-sock': No such file or directory
 Failed to connect socket to '/var/run/libvirt/virtqemud-sock-ro': Connection refused

If you have just installed libvirt and virt-v2v, then you may see the errors above. This is caused by libvirt daemons that provide various services not running straight after installation. (This may depend on your distribution and vendor presets).

To fix this on systemd-based distributions, do:

 systemctl isolate multi-user.target

See also https://bugzilla.redhat.com/2182024.

ファイル

/usr/share/virtio-win
    (Optional)

    If this directory is present, then virtio drivers for Windows guests will be found from this directory and installed in the guest during conversion.

環境変数

"VIRT_V2V_TMPDIR"
"LIBGUESTFS_CACHEDIR"
    Location of the temporary directory used for the potentially large temporary overlay file. If neither environment variable is set then /var/tmp is used.

    To reliably ensure large temporary files are cleaned up (for example in case virt-v2v crashes) you should create a randomly named directory under /var/tmp, set "VIRT_V2V_TMPDIR" to point to this directory, then when virt-v2v exits remove the directory.

    See the "Disk space" section above.

"VIRT_TOOLS_DATA_DIR"
    This can point to the directory containing data files used for Windows conversion.

    Normally you do not need to set this. If not set, a compiled-in default will be used (something like /usr/share/virt-tools).

    This directory may contain the following files:

    rhsrvany.exe
        (Required when doing conversions of Windows guests)

        This is the RHSrvAny Windows binary, used to install a "firstboot" script in the guest during conversion of Windows guests.

        See also: "https://github.com/rwmjones/rhsrvany"

    pnp_wait.exe
        (Recommended when doing conversions of Windows guests)

        This tool waits for newly installed Windows devices to become available before trying to configure them, for example to set network configuration. It is part of the RHSrvAny project.

    pvvxsvc.exe
        This is a Windows binary shipped with SUSE VMDP, used to install a "firstboot" script in Windows guests. It is an alternative to RHSrvAny.

"VIRTIO_WIN"
    This is an override for where virtio drivers for Windows are searched for. It can be a directory or point to virtio-win.iso (CD ROM image containing drivers).

    If unset, then we look for drivers via whichever of these methods succeeds first:

    /usr/share/virtio-win/virtio-win.iso
        The ISO containing virtio drivers for Windows.

    /usr/share/virtio-win
        The exploded tree of virtio drivers for Windows.

    See "Enabling virtio".

他の環境変数は "環境変数" in guestfs(3) を参照してください。

OTHER TOOLS

engine-image-uploader(8)
    Variously called "engine-image-uploader", "ovirt-image-uploader" or "rhevm-image-uploader", this tool allows you to copy a guest from one oVirt Export Storage Domain to another. It only permits importing a guest that was previously exported from another oVirt instance.

import-to-ovirt.pl
    This script can be used to import guests that already run on KVM to oVirt. For more information, see this blog posting by the author of virt-v2v:

    https://rwmj.wordpress.com/2015/09/18/importing-kvm-guests-to-ovirt-or-rhev/#content

関連項目
virt-p2v(1), virt-v2v-inspector(1), virt-v2v-in-place(1), virt-v2v-open(1), virt-customize(1), virt-df(1), virt-filesystems(1), virt-inspector(1), virt-sparsify(1), virt-sysprep(1), virt-win-reg(1), guestfs(3), guestfish(1), qemu-img(1), engine-image-uploader(8), import-to-ovirt.pl, nbdkit(1), nbdkit-vddk-plugin(1), http://libguestfs.org/.

著者
Matthew Booth

Cédric Bosdonnat

Laszlo Ersek

Tomáš Golembiovský

Shahar Havivi

Richard W.M. Jones

Roman Kagan

Mike Latimer

Nir Soffer

Pino Toscano

Xiaodai Wang

Ming Xie

Tingting Zheng

COPYRIGHT
Copyright (C) 2009-2025 Red Hat Inc.

LICENSE

BUGS
To get a list of bugs against libguestfs, use this link: https://bugzilla.redhat.com/buglist.cgi?component=libguestfs&product=Virtualization+Tools

To report a new bug against libguestfs, use this link: https://bugzilla.redhat.com/enter_bug.cgi?component=libguestfs&product=Virtualization+Tools

When reporting a bug, please supply:

•   The version of libguestfs.

•   Where you got libguestfs (eg. which Linux distro, compiled from source, etc)

•   Describe the bug accurately and give a way to reproduce it.

•   Run libguestfs-test-tool(1) and paste the complete, unedited output into the bug report.