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.
32 Note that virt-what will print this fact for baremetal AWS instances,
33 which you might not consider to be true virtualization. In this case
34 other facts (eg. C<kvm> or C<xen>) would I<not> be present.
36 Status: contributed by Qi Guo, Vitaly Kuznetsov, confirmed by RWMJ.
40 This is a bhyve (FreeBSD hypervisor) guest.
42 Status: contributed by Leonardo Brondani Schenkel.
46 This is a Docker container.
48 Status: confirmed by Charles Nguyen
52 This is Microsoft Hyper-V hypervisor.
54 Status: confirmed by RWMJ
56 =item B<ibm_power-kvm>
58 This is an IBM POWER KVM guest.
60 Status: contributed by Adrian Likins.
62 =item B<ibm_power-lpar_shared>
64 =item B<ibm_power-lpar_dedicated>
66 This is an IBM POWER LPAR (hardware partition) in either shared
69 Status: contributed by Adrian Likins.
73 This is an IBM SystemZ (or other S/390) hardware partitioning system.
74 Additional facts listed below may also be printed.
76 =item B<ibm_systemz-direct>
78 This is Linux running directly on a IBM SystemZ hardware partitioning
81 This is expected to be a highly unusual configuration - if
82 you see this result you should treat it with suspicion.
86 =item B<ibm_systemz-lpar>
88 This is Linux running directly on an LPAR on an IBM SystemZ
89 hardware partitioning system.
91 Status: confirmed by Thomas Huth
93 =item B<ibm_systemz-zvm>
95 This is a z/VM guest running in an LPAR on an IBM SystemZ
96 hardware partitioning system.
98 Status: confirmed by RWMJ using a Fedora guest running in z/VM
100 =item B<ibm_systemz-kvm>
102 This is a KVM guest running on an IBM System Z hardware system.
104 Status: contributed by Thomas Huth
108 The guest appears to be running on an Linux SPARC system with
109 Oracle VM Server for SPARC (Logical Domains) support.
111 Status: contributed by Darren Kenny
113 =item B<ldoms-control>
115 The is the Oracle VM Server for SPARC (Logical Domains) control domain.
117 Status: contributed by Darren Kenny
121 The is the Oracle VM Server for SPARC (Logical Domains) guest domain.
123 Status: contributed by Darren Kenny
127 The is the Oracle VM Server for SPARC (Logical Domains) I/O domain.
129 Status: contributed by Darren Kenny
133 The is the Oracle VM Server for SPARC (Logical Domains) Root domain.
135 Status: contributed by Darren Kenny
137 =item B<linux_vserver>
139 This is printed for backwards compatibility with older virt-what which
140 could not distinguish between a Linux VServer container guest and
143 =item B<linux_vserver-guest>
145 This process is running in a Linux VServer container.
147 Status: contributed by Barış Metin
149 =item B<linux_vserver-host>
151 This process is running as the Linux VServer host (VxID 0).
153 Status: contributed by Barış Metin and Elan Ruusamäe
157 This process is running in a Linux LXC container.
159 Status: contributed by Marc Fournier
163 This guest is running on the KVM hypervisor using hardware
166 Note that if the hypervisor is using software acceleration
167 you should I<not> see this, but should see the C<qemu> fact
170 Status: confirmed by RWMJ.
174 This guest is running on the KVM hypervisor using hardware
175 acceleration, and the userspace component of the hypervisor
176 is lkvm (a.k.a kvmtool).
178 Status: contributed by Andrew Jones
182 The guest appears to be running inside an OpenVZ or Virtuozzo
185 Status: contributed by Evgeniy Sokolov
189 The guest is running on an oVirt node.
190 (See also C<rhev> below).
192 Status: contributed by RWMJ, not confirmed
196 The guest is running inside Parallels Virtual Platform
197 (Parallels Desktop, Parallels Server).
199 Status: contributed by Justin Clift
201 =item B<powervm_lx86>
203 The guest is running inside IBM PowerVM Lx86 Linux/x86 emulator.
205 Status: data originally supplied by Jeffrey Scheel, confirmed by
206 Yufang Zhang and RWMJ
210 This is QEMU hypervisor using software emulation.
212 Note that for KVM (hardware accelerated) guests you should I<not> see
215 Status: confirmed by RWMJ.
219 The guest is running on a Red Hat Enterprise Virtualization (RHEV) node.
221 Status: confirmed by RWMJ
225 This is a User-Mode Linux (UML) guest.
227 Status: contributed by Laurent Léonard
231 Some sort of virtualization appears to be present, but we are not sure
232 what it is. In some very rare corner cases where we know that
233 virtualization is hard to detect, we will try a timing attack to see
234 if certain machine instructions are running much more slowly than they
235 should be, which would indicate virtualization. In this case, the
236 generic fact C<virt> is printed.
240 This is Hitachi Virtualization Manager (HVM) Virtage
241 hardware partitioning system.
243 Status: data supplied by Bhavna Sarathy, not confirmed
247 This is a VirtualBox guest.
249 Status: contributed by Laurent Léonard
253 The guest appears to be running on Microsoft VirtualPC.
255 Status: not confirmed
259 This is a vmm (OpenBSD hypervisor) guest.
261 Status: contributed by Jasper Lievisse Adriaanse.
265 The guest appears to be running on VMware hypervisor.
267 Status: confirmed by RWMJ
271 The guest appears to be running on Xen hypervisor.
273 Status: confirmed by RWMJ
277 This is the Xen dom0 (privileged domain).
279 Status: confirmed by RWMJ
283 This is a Xen domU (paravirtualized guest domain).
285 Status: confirmed by RWMJ
289 This is a Xen guest fully virtualized (HVM).
291 Status: confirmed by RWMJ
297 Programs that use or wrap C<virt-what> should check that the exit
298 status is 0 before they attempt to parse the output of the command.
300 A non-zero exit status indicates some error, for example, an
301 unrecognized command line argument. If the exit status is non-zero
302 then the output "facts" (if any were printed) cannot be guaranteed and
305 The exit status does I<not> have anything to do with whether the
306 program is running on baremetal or under virtualization, nor with
307 whether C<virt-what> managed detection "correctly" (which is basically
308 unknowable given the large variety of virtualization systems out there
309 and that some systems deliberately emulate others).
311 =head1 RUNNING VIRT-WHAT FROM OTHER PROGRAMS
313 C<virt-what> is designed so that you can easily run it from
314 other programs or wrap it up in a library.
316 Your program should check the exit status (see the section above).
318 Some programming languages (notably Python: issue 1652) erroneously
319 mask the C<SIGPIPE> signal and do not restore it when executing
320 subprocesses. C<virt-what> is a shell script and some shell commands
321 do not work correctly when you do this. You may see warnings from
322 C<virt-what> similar to this:
324 echo: write error: Broken pipe
326 The solution is to set the C<SIGPIPE> signal handler back to C<SIG_DFL>
327 before running C<virt-what>.
329 =head1 IMPORTANT NOTE
331 Most of the time, using this program is the I<wrong> thing to do.
332 Instead you should detect the specific features you actually want to
333 use. (As an example, if you wanted to issue Xen hypervisor commands
334 you would look for the C</proc/xen/privcmd> file).
336 However people keep asking for this, so we provide it. There are a
341 =item Bug reporting tool
343 If you think that virtualization could affect how your program runs,
344 then you might use C<virt-what> to report this in a bug reporting
347 =item Status display and monitoring tools
349 You might include this information in status and monitoring programs.
351 =item System tuning (sometimes)
353 You might use this program to tune an operating system so it runs
354 better as a virtual machine of a particular hypervisor. However if
355 installing paravirtualized drivers, it's better to check for the
356 specific features your drivers need (eg. for the presence of PCI devices).
362 L<http://people.redhat.com/~rjones/virt-what/>,
363 L<http://www.vmware.com/>,
364 L<http://www.microsoft.com/windows/products/winfamily/virtualpc>,
365 L<http://xensource.com/>,
366 L<http://bellard.org/qemu/>,
367 L<http://kvm.qumranet.com/>,
368 L<http://openvz.org/>
372 Richard W.M. Jones <rjones @ redhat . com>
376 (C) Copyright 2008-2015 Red Hat Inc.,
377 L<http://people.redhat.com/~rjones/virt-what/>
379 This program is free software; you can redistribute it and/or modify
380 it under the terms of the GNU General Public License as published by
381 the Free Software Foundation; either version 2 of the License, or
382 (at your option) any later version.
384 This program is distributed in the hope that it will be useful,
385 but WITHOUT ANY WARRANTY; without even the implied warranty of
386 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
387 GNU General Public License for more details.
389 You should have received a copy of the GNU General Public License
390 along with this program; if not, write to the Free Software
391 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
393 =head1 REPORTING BUGS
395 Bugs can be viewed on the Red Hat Bugzilla page:
396 L<https://bugzilla.redhat.com/>.
398 If you find a bug in virt-what, please follow these steps to report it:
402 =item 1. Check for existing bug reports
404 Go to L<https://bugzilla.redhat.com/> and search for similar bugs.
405 Someone may already have reported the same bug, and they may even
408 =item 2. Capture debug and error messages
412 virt-what > virt-what.log 2>&1
414 and keep I<virt-what.log>. It may contain error messages which you
415 should submit with your bug report.
417 =item 3. Get version of virt-what.
423 =item 4. Submit a bug report.
425 Go to L<https://bugzilla.redhat.com/> and enter a new bug.
426 Please describe the problem in as much detail as possible.
428 Remember to include the version numbers (step 3) and the debug
429 messages file (step 2) and as much other detail as possible.
431 =item 5. Assign the bug to rjones @ redhat.com
433 Assign or reassign the bug to B<rjones @ redhat.com> (without the
434 spaces). You can also send me an email with the bug number if you
435 want a faster response.