2 virt-p2v - P2V (physical to virtual machine) migration tool
8 virt-p2v is a live CD for migrating physical machines to virtual machine
11 In the simplest mode of operation, you take a pre-built live CD ISO from
12 the main website (<http://et.redhat.com/~rjones/virt-p2v/>) and burn it
13 to a CD-R. Then insert the CD-R into the physical machine which must be
14 migrated, reboot, and follow the on-screen instructions. See STANDARD
17 You may also build a customized live CD. Typically this will contain
18 things like server details specific to your organization, so that the
19 live CD can run mostly or completely automatically. See BUILDING A
20 CUSTOM LIVE CD section below.
22 In both cases, files and disk images are transferred from the physical
23 machine over the network to the virtualization host machine over ssh.
24 Therefore "sshd" must be running on the virtualization host, and must be
25 accessible to that host. See SERVER REQUIREMENTS section below.
27 The "virt-p2v" script must only be run from the live CD. It isn't
28 designed to run outside this environment and could do Bad Things to your
29 machine if you try it. The script contains some checks to try to stop
32 Virt-p2v does not modify the physical machine, its disks, configuration
36 After booting the live CD-R, you are presented with a series of
37 questions. This section explains each question.
40 Enter the name or IP address of the virtualization host. This is the
41 host running Xen (or any other virtualization system supported by
42 libvirt, eg. QEMU). This host should be accessible on the network
43 and running an SSH daemon ("sshd").
46 This is the port name or number of the SSH server on the remote
47 host. The default is 22 which is the standard SSH port.
50 Enter the directory on the remote host where disk image(s) and
51 configuration file(s) must reside.
53 Note that if the remote host is running SELinux then you may not be
54 able to start a Xen guest unless its disk image(s) are located in
55 the default directory, "/var/lib/xen/images".
58 Enter the remote SSH username to use to log in to the remote host.
60 If you use the default username of "root" then you should ensure
61 that remote root logins are enabled on the remote host (ie.
62 "PermitRootLogin yes" in "/etc/ssh/sshd_config").
65 Choose the way that the live CD configures network access. The
68 Automatic configuration
69 In this mode, the live CD attempts to reuse the network
70 configuration from the physical machine's root filesystem. You
71 should probably try this method even though occasionally it does
74 Configure from the shell
75 In this mode you will be dropped into a command shell and you
76 will need to issue the correct sequence of "/sbin/ifconfig"
77 commands in order to configure the network interface.
79 A typical sequence of commands which should bring up the network
82 /sbin/ifconfig eth0 AA.BB.CC.DD
83 /sbin/route add default gw GG.HH.II.JJ eth0
85 where "AA.BB.CC.DD" is the IP address and "GG.HH.II.JJ" is the
89 This question lists out all local block devices (hard disk drives
90 and similar) and asks you to choose which will be sent to the remote
91 host. You must send at least one block device.
94 This question lists out possible root filesystems and asks you to
95 choose the right one. Choose the filesystem which would normally be
96 mounted as "/" on the system.
98 Virt-p2v performs some autodetection and is in most cases able to
99 work out which filesystems are possible root filesystems. It
100 displays what it thinks is on each filesystem, but leaves it up to
101 the user to make a final decision.
103 The root filesystem is critical because it contains "/etc/fstab".
104 This is used during P2V both to determine how other filesystems are
105 normally mounted on the machine, and because this file and others
106 under "/etc" may need to be modified during P2V conversion.
108 If the machine has more than one root filesystem (typically because
109 the machine is dual-booted with another operating system), then you
110 must choose only one of them to perform the P2V conversion on.
113 This question asks you to choose the hypervisor / virtualization
114 system in use on the remote host.
116 If you select *Xen*, *QEMU* or *KVM* then virt-p2v will produce a
117 configuration file which is customized for the selected system. If
118 you select *Other* then virt-p2v will produce a generic
119 configuration file which will probably require hand-modification to
122 See also <http://libvirt.org/format.html>.
125 This question asks you to choose the machine architecture. Virt-p2v
126 can normally detect this, so you should leave it as *Auto-detect*.
129 This question asks you to choose the amount of memory (RAM) in
130 megabytes assigned to the virtual machine.
132 If the entry is left blank, then virt-p2v will try to autodetect how
133 much RAM is present in the physical machine and use that, and this
134 is probably a good choice for most simple migrations.
137 This question asks you to choose the number of virtual CPUs assigned
138 to the virtual machine. Choosing 1 causes the virtual machine to be
139 uniprocessor, and choosing some number greater than 1 causes the
140 virtual machine to be SMP.
142 If the entry is left blank, then virt-p2v will try to autodetect how
143 many CPU cores are present in the physical machine and use that, and
144 this is probably a good choice for most simple migrations.
147 Here you should enter a MAC address for the virtual machine's
148 emulated network card. MAC addresses are written as
149 "aa:bb:cc:dd:ee:ff" where "aa", "bb" etc are hexadecimal octets.
151 Leaving it blank will cause virt-p2v to choose a random MAC address
152 within the "00:16:3e:.." space reserved for Xen guests. These MAC
153 addresses are not tested for uniqueness so there is a very small
154 chance that they could coincide, which would leave a guest unable to
155 access the virtual network.
158 In this step you are asked to verify the settings above. If any are
159 incorrect, use the *Back* button to navigate back to the setting. If
160 all settings are correct, use the *OK* button to begin the P2V
163 Network autoconfiguration
164 If you selected network autoconfiguration above then virt-p2v tries
165 to autoconfigure the network and ping the remote host. It then asks
166 *Did automatic network configuration work?*
168 You should answer "y" here if it worked.
170 Answering "n" will drop you into a command shell.
172 You can also switch to another virtual console if you need to
173 perform additional tests. See section GETTING A SHELL below.
176 Unless you have set up an SSH key, or the SSH server on the remote
177 host allows passwordless logins, then for each file that has to be
178 transferred to the remote host you will need to confirm the identity
179 of the remote host and/or enter a password.
181 To understand more about this, please see the ssh(1) manual page.
183 BOOTING P2V GUEST ON VIRTUALIZATION HOST
184 Once the P2V conversion has been completed, and assuming it was
185 successful, you will find a configuration file and one or more disk
186 images on the remote host.
188 The files will be located in the directory selected, usually
189 "/var/lib/xen/images". The names of the files are made up of:
191 "p2v-*hostname*-*YYYYMMDDHHMM*.conf" or
192 "p2v-*hostname*-*YYYYMMDDHHMM*-hd*X*.img"
194 To simply start up the guest, use the following commands as root:
196 virsh define p2v-foo-2008MMDDHHMM.conf
201 virsh -c qemu:///system define p2v-foo-2008MMDDHHMM.conf
202 virsh -c qemu:///system start foo
204 For other hypervisors you will need to edit the configuration file and
205 read <http://libvirt.org/uri.html>.
208 During all stages of P2V questions and conversion you can get a root
209 shell on the physical machine. Use *ALT* *F2* keys to switch to the
210 second virtual console, then log in as *root* with no password.
213 Virt-p2v writes a detailed log file to "/tmp/virt-p2v.log". (Note that
214 this "/tmp" directory is a ramdisk on the live CD, not the same as the
215 "/tmp" directory of the physical machine, and more importantly it
216 disappears when the machine is rebooted).
218 If you are reporting a bug, please always supply this file.
221 The virtualization host (remote host) must be running an SSH daemon
222 ("sshd"), accessible from the physical machine which is being migrated.
224 Previous versions of virt-p2v could use a special virt-p2v server.
225 However this capability has been removed since there was practically no
228 BUILDING A CUSTOM LIVE CD
229 To build a custom live CD you must download the source for virt-p2v from
230 <http://et.redhat.com/~rjones/virt-p2v/> or from the Mercurial source
231 repository (see website for details).
233 Please read the "README" file to find the dependencies which are all in
234 Fedora > 8 or EPEL > 5.
236 The steps to creating a custom live CD are:
238 1. Edit "virt-p2v" and adjust defaults
239 Find the section "TO MAKE A CUSTOM virt-p2v SCRIPT ..." which is
240 near to the top of this file. Edit the defaults in this section as
243 2. "virt-p2v --test" to verify your changes
244 This command should not print anything at all. If it prints any
245 message, then you will need to fix the error by going back to the
248 3. "make build" or "make update" to build a custom live CD
249 "make build" will create a complete ISO from scratch. "make update"
250 can be used to build a "quick" developer ISO by updating an existing
251 ISO image. See section ISO ATTACHMENTS below for more details.
253 4. Burn the ISO to a CD-R and test
255 EDITING DEFAULTS IN THE "virt-p2v" SCRIPT
256 For each default, setting it to "None" will ask the user. All of the
257 defaults are set to "None" in the standard, uncustomized virt-p2v
258 script, and so the standard script asks all the questions.
260 You may edit "virt-p2v" and change the defaults, in which case the user
261 will not be questioned. In this way you can make the script partially or
264 *Note about OCaml code:* "None" and "Some foo" are similar to the
265 concept of a NULL pointer versus non-NULL pointer in other languages.
266 This a variant type defined as:
268 type α option = None | Some of α
271 If this is "true" then we wait for a keypress after boot and at a
272 couple of other stages. If set to "false" then we try not to wait
273 for any keypresses (so more automated live CDs are possible).
276 Set this to "Some "hostname"" or "Some "IP-address"" to provide the
277 name of the remote host.
280 Set this to "Some port" (eg. "Some 22") to provide the port number
281 of the remote host's SSH daemon.
284 Set this to "Some "path"" (eg. "Some "/var/lib/xen/images"") to
285 provide the directory where we update P2V converted images and
289 Set this to "Some "username"" (eg. "Some "root"") to provide the SSH
290 username to use on the remote system.
293 Set this to a list of block devices to send to the remote system.
294 For example, "Some ["sda"; "sdb"]".
297 Set this to the name of the root filesystem.
299 For a disk partition (eg. "/dev/sda1"), use:
301 Some (Part ("sda", "1"))
303 For a logical volume (eg. "/dev/VolGroup00/LogVol00"), use:
305 Some (LV ("VolGroup00", "LogVol00"))
308 Set this to the choice for network setup. Use either "Some Auto" or
309 "Some Shell" for auto-configuration or shell (manual) configuration
313 Set this to the choice of hypervisor or virtualization system. The
314 choices are: "Some Xen", "Some QEMU" or "Some KVM".
317 Set this to the architecture. The choices are: "Some I386" (i386 and
318 up, 32 bit), "Some X86_64" (AMD and Intel x86-64, 64 bit), "Some
319 IA64" (Intel IA64), "Some PPC" (PowerPC, 32 bit), "Some PPC64"
320 (PowerPC, 64 bit), "Some SPARC" (Sun SPARC, 32 bit), "Some SPARC64"
321 (Sun SPARC, 64 bit), "OtherArch "foo"" (a hypothetical architecture
322 called *foo*), or "UnknownArch" to auto-detect the architecture.
325 Set this to the size of memory in megabytes, eg. "Some 256". If you
326 set this to "Some 0" then virt-p2v will try to autodetect the amount
327 of RAM installed on the physical machine.
330 Set this to the number of virtual CPUs, eg. "Some 1". If you set
331 this to "Some 0" then virt-p2v will try to autodetect the number of
332 CPU cores on the physical machine.
335 Set this to the MAC address for the virtual network card, eg. "Some
336 "aa:bb:cc:dd:ee:ff"". If you set this to "Some """ then virt-p2v
337 will choose a random MAC address within the "00:16:3e:.." space
338 reserved for Xen guests. These MAC addresses are not tested for
339 uniqueness so there is a very small chance that they could coincide,
340 which would leave a guest unable to access the virtual network.
343 Rebuilding a custom ISO is time-consuming. You can make a "quick"
344 developer ISO by updating an existing ISO image with a new custom
345 "virt-p2v" script. This is useful for testing purposes.
347 From the source directory, assuming that you have downloaded or built an
348 existing "virt-p2v-*.iso", you can just do:
352 or the equivalent manual command:
354 ./iso-attach virt-p2v-VERSION.iso virt-p2v
356 BOOTING FROM A USB KEY INSTEAD OF A CD
357 If you wish to boot from a USB keydrive, use the livecd-iso-to-disk
360 livecd-iso-to-disk virt-p2v-$VERSION.iso /dev/sdX1
362 (Replace /dev/sdX1 with the actual USB device).
364 In my experience I also had to set up a suitable MBR:
366 cat /usr/lib/syslinux/mbr.bin > /dev/sdX
368 TESTING AN ISO UNDER QEMU OR KVM
369 If you have a virtual guest running under QEMU or KVM then you can test
370 the P2V conversion process on the guest.
372 (Technically this is a V2V -- virtual to virtual -- conversion).
374 From the source directory do:
376 make boot HDA=qemuimage.img
378 where "qemuimage.img" is the name of the QEMU/KVM image.
380 You can also supply an "HDB" parameter to specify a second disk.
383 Please direct questions to the et-mgmt-tools mailing list
384 <http://www.redhat.com/mailman/listinfo/et-mgmt-tools> <et-mgmt-tools @
388 virsh(1), <http://www.libvirt.org/ocaml/>, <http://www.libvirt.org/>,
389 <http://et.redhat.com/~rjones/>, <http://caml.inria.fr/>
392 Richard W.M. Jones <rjones @ redhat . com>
395 (C) Copyright 2007-2008 Red Hat Inc., Richard W.M. Jones
398 This program is free software; you can redistribute it and/or modify it
399 under the terms of the GNU General Public License as published by the
400 Free Software Foundation; either version 2 of the License, or (at your
401 option) any later version.
403 This program is distributed in the hope that it will be useful, but
404 WITHOUT ANY WARRANTY; without even the implied warranty of
405 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
406 Public License for more details.
408 You should have received a copy of the GNU General Public License along
409 with this program; if not, write to the Free Software Foundation, Inc.,
410 675 Mass Ave, Cambridge, MA 02139, USA.
413 Bugs can be viewed on the Red Hat Bugzilla page:
414 <https://bugzilla.redhat.com/>.
416 If you find a bug in virt-p2v, please follow these steps to report it:
418 1. Check for existing bug reports
419 Go to <https://bugzilla.redhat.com/> and search for similar bugs.
420 Someone may already have reported the same bug, and they may even
423 2. Capture debug and error messages
424 At the point where you get the error or unexpected behaviour, go to
425 the second virtual console (*ALT* *F2*) and look at the logfile
426 "/tmp/virt-p2v.log". Please make sure that this file is attached to
429 3. Get version of virt-p2v
430 The version is in the name of the ISO. If you have built a custom
431 virt-p2v ISO, please describe any changes that you have made.
433 4. Submit a bug report.
434 Go to <https://bugzilla.redhat.com/> and enter a new bug. Please
435 describe the problem in as much detail as possible.
437 Remember to include the version number (step 3) and to attach the
440 5. Assign the bug to rjones @ redhat.com
441 Assign or reassign the bug to rjones @ redhat.com (without the
442 spaces). You can also send me an email with the bug number if you
443 want a faster response.