5 virt-what - detect if we are running in a virtual machine
13 C<virt-what> is a shell script which can be used to detect if the
14 program is running in a virtual machine.
16 The program prints out a list of "facts" about the virtual machine,
17 derived from heuristics. One fact is printed per line.
19 If nothing is printed and the script exits with code 0 (no error),
20 then it can mean I<either> that the program is running on bare-metal
21 I<or> the program is running inside a type of virtual machine which we
22 don't know about or cannot detect.
28 =item B<alibaba_cloud>
30 =item B<alibaba_cloud-x_dragon>
32 This is a cloud computing service based on Alibaba Cloud.
34 Status: contributed by Weisson.
40 Note that virt-what will print this fact for baremetal AWS instances,
41 which you might not consider to be true virtualization. In this case
42 other facts (eg. C<kvm> or C<xen>) would I<not> be present.
44 Status: contributed by Qi Guo, Vitaly Kuznetsov, confirmed by RWMJ.
48 This is a bhyve (FreeBSD hypervisor) guest.
50 Status: contributed by Leonardo Brondani Schenkel.
54 This is a Docker container.
56 Status: confirmed by Charles Nguyen
60 This is Microsoft Hyper-V hypervisor.
62 Status: confirmed by RWMJ
64 =item B<ibm_power-kvm>
66 This is an IBM POWER KVM guest.
68 Status: contributed by Adrian Likins.
70 =item B<ibm_power-lpar_shared>
72 =item B<ibm_power-lpar_dedicated>
74 This is an IBM POWER LPAR (hardware partition) in either shared
77 Status: contributed by Adrian Likins.
81 This is an IBM SystemZ (or other S/390) hardware partitioning system.
82 Additional facts listed below may also be printed.
84 =item B<ibm_systemz-direct>
86 This is Linux running directly on a IBM SystemZ hardware partitioning
89 This is expected to be a highly unusual configuration - if
90 you see this result you should treat it with suspicion.
94 =item B<ibm_systemz-lpar>
96 This is Linux running directly on an LPAR on an IBM SystemZ
97 hardware partitioning system.
99 Status: confirmed by Thomas Huth
101 =item B<ibm_systemz-zvm>
103 This is a z/VM guest running in an LPAR on an IBM SystemZ
104 hardware partitioning system.
106 Status: confirmed by RWMJ using a Fedora guest running in z/VM
108 =item B<ibm_systemz-kvm>
110 This is a KVM guest running on an IBM System Z hardware system.
112 Status: contributed by Thomas Huth
116 The guest appears to be running on an Linux SPARC system with
117 Oracle VM Server for SPARC (Logical Domains) support.
119 Status: contributed by Darren Kenny
121 =item B<ldoms-control>
123 The is the Oracle VM Server for SPARC (Logical Domains) control domain.
125 Status: contributed by Darren Kenny
129 The is the Oracle VM Server for SPARC (Logical Domains) guest domain.
131 Status: contributed by Darren Kenny
135 The is the Oracle VM Server for SPARC (Logical Domains) I/O domain.
137 Status: contributed by Darren Kenny
141 The is the Oracle VM Server for SPARC (Logical Domains) Root domain.
143 Status: contributed by Darren Kenny
145 =item B<linux_vserver>
147 This is printed for backwards compatibility with older virt-what which
148 could not distinguish between a Linux VServer container guest and
151 =item B<linux_vserver-guest>
153 This process is running in a Linux VServer container.
155 Status: contributed by Barış Metin
157 =item B<linux_vserver-host>
159 This process is running as the Linux VServer host (VxID 0).
161 Status: contributed by Barış Metin and Elan Ruusamäe
165 This process is running in a Linux LXC container.
167 Status: contributed by Marc Fournier
171 This guest is running on the KVM hypervisor using hardware
174 Note that if the hypervisor is using software acceleration
175 you should I<not> see this, but should see the C<qemu> fact
178 Status: confirmed by RWMJ.
182 This guest is running on the KVM hypervisor using hardware
183 acceleration, and the userspace component of the hypervisor
184 is lkvm (a.k.a kvmtool).
186 Status: contributed by Andrew Jones
190 The guest is running inside Nutanix Acropolis Hypervisor (AHV).
192 Status: confirmed by RWMJ.
196 The guest appears to be running inside an OpenVZ or Virtuozzo
199 Status: contributed by Evgeniy Sokolov
203 The guest is running on an oVirt node.
204 (See also C<rhev> below).
206 Status: contributed by RWMJ, not confirmed
210 The guest is running inside Parallels Virtual Platform
211 (Parallels Desktop, Parallels Server).
213 Status: contributed by Justin Clift
217 This is a Podman container.
219 Status: contributed by Jordan Webb
221 =item B<powervm_lx86>
223 The guest is running inside IBM PowerVM Lx86 Linux/x86 emulator.
225 Status: data originally supplied by Jeffrey Scheel, confirmed by
226 Yufang Zhang and RWMJ
230 This is QEMU hypervisor using software emulation.
232 Note that for KVM (hardware accelerated) guests you should I<not> see
235 Status: confirmed by RWMJ.
239 The guest is running on a Red Hat Enterprise Virtualization (RHEV) node.
241 Status: confirmed by RWMJ
245 This is a User-Mode Linux (UML) guest.
247 Status: contributed by Laurent Léonard
251 Some sort of virtualization appears to be present, but we are not sure
252 what it is. In some very rare corner cases where we know that
253 virtualization is hard to detect, we will try a timing attack to see
254 if certain machine instructions are running much more slowly than they
255 should be, which would indicate virtualization. In this case, the
256 generic fact C<virt> is printed.
260 This is Hitachi Virtualization Manager (HVM) Virtage
261 hardware partitioning system.
263 Status: data supplied by Bhavna Sarathy, not confirmed
267 This is a VirtualBox guest.
269 Status: contributed by Laurent Léonard
273 The guest appears to be running on Microsoft VirtualPC.
275 Status: not confirmed
279 This is a vmm (OpenBSD hypervisor) guest.
281 Status: contributed by Jasper Lievisse Adriaanse.
285 The guest appears to be running on VMware hypervisor.
287 Status: confirmed by RWMJ
291 The guest appears to be running on Xen hypervisor.
293 Status: confirmed by RWMJ
297 This is the Xen dom0 (privileged domain).
299 Status: confirmed by RWMJ
303 This is a Xen domU (paravirtualized guest domain).
305 Status: confirmed by RWMJ
309 This is a Xen guest fully virtualized (HVM).
311 Status: confirmed by RWMJ
317 Programs that use or wrap C<virt-what> should check that the exit
318 status is 0 before they attempt to parse the output of the command.
320 A non-zero exit status indicates some error, for example, an
321 unrecognized command line argument. If the exit status is non-zero
322 then the output "facts" (if any were printed) cannot be guaranteed and
325 The exit status does I<not> have anything to do with whether the
326 program is running on baremetal or under virtualization, nor with
327 whether C<virt-what> managed detection "correctly" (which is basically
328 unknowable given the large variety of virtualization systems out there
329 and that some systems deliberately emulate others).
331 =head1 RUNNING VIRT-WHAT FROM OTHER PROGRAMS
333 C<virt-what> is designed so that you can easily run it from
334 other programs or wrap it up in a library.
336 Your program should check the exit status (see the section above).
338 Some programming languages (notably Python: issue 1652) erroneously
339 mask the C<SIGPIPE> signal and do not restore it when executing
340 subprocesses. C<virt-what> is a shell script and some shell commands
341 do not work correctly when you do this. You may see warnings from
342 C<virt-what> similar to this:
344 echo: write error: Broken pipe
346 The solution is to set the C<SIGPIPE> signal handler back to C<SIG_DFL>
347 before running C<virt-what>.
349 =head1 IMPORTANT NOTE
351 Most of the time, using this program is the I<wrong> thing to do.
352 Instead you should detect the specific features you actually want to
353 use. (As an example, if you wanted to issue Xen hypervisor commands
354 you would look for the C</proc/xen/privcmd> file).
356 However people keep asking for this, so we provide it. There are a
361 =item Bug reporting tool
363 If you think that virtualization could affect how your program runs,
364 then you might use C<virt-what> to report this in a bug reporting
367 =item Status display and monitoring tools
369 You might include this information in status and monitoring programs.
371 =item System tuning (sometimes)
373 You might use this program to tune an operating system so it runs
374 better as a virtual machine of a particular hypervisor. However if
375 installing paravirtualized drivers, it's better to check for the
376 specific features your drivers need (eg. for the presence of PCI devices).
382 L<http://people.redhat.com/~rjones/virt-what/>,
383 L<http://www.vmware.com/>,
384 L<http://www.microsoft.com/windows/products/winfamily/virtualpc>,
385 L<http://xensource.com/>,
386 L<http://bellard.org/qemu/>,
387 L<http://kvm.qumranet.com/>,
388 L<http://openvz.org/>
392 Richard W.M. Jones <rjones @ redhat . com>
396 (C) Copyright 2008-2015 Red Hat Inc.,
397 L<http://people.redhat.com/~rjones/virt-what/>
399 This program is free software; you can redistribute it and/or modify
400 it under the terms of the GNU General Public License as published by
401 the Free Software Foundation; either version 2 of the License, or
402 (at your option) any later version.
404 This program is distributed in the hope that it will be useful,
405 but WITHOUT ANY WARRANTY; without even the implied warranty of
406 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
407 GNU General Public License for more details.
409 You should have received a copy of the GNU General Public License
410 along with this program; if not, write to the Free Software
411 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
413 =head1 REPORTING BUGS
415 Bugs can be viewed on the Red Hat Bugzilla page:
416 L<https://bugzilla.redhat.com/>.
418 If you find a bug in virt-what, please follow these steps to report it:
422 =item 1. Check for existing bug reports
424 Go to L<https://bugzilla.redhat.com/> and search for similar bugs.
425 Someone may already have reported the same bug, and they may even
428 =item 2. Capture debug and error messages
432 virt-what > virt-what.log 2>&1
434 and keep I<virt-what.log>. It may contain error messages which you
435 should submit with your bug report.
437 =item 3. Get version of virt-what.
443 =item 4. Submit a bug report.
445 Go to L<https://bugzilla.redhat.com/> and enter a new bug.
446 Please describe the problem in as much detail as possible.
448 Remember to include the version numbers (step 3) and the debug
449 messages file (step 2) and as much other detail as possible.
451 =item 5. Assign the bug to rjones @ redhat.com
453 Assign or reassign the bug to B<rjones @ redhat.com> (without the
454 spaces). You can also send me an email with the bug number if you
455 want a faster response.